Households Behaviour towards Sustainable Energy Management in Poland—The Homo Energeticus Concept as a New Behaviour Pattern in Sustainable Economics

: The presented article belongs to the research school of sustainable development economics as a relatively new science discipline within the broader area of heterodox economics. This paper is based on literature studies of homo concepts in economics, sociology and psychology. It identiﬁes a research gap in sustainable economics, especially in sustainable energy management, formulating a novel concept of an economic man involved in energy management called homo energeticus. Homo energeticus concept is veriﬁed by empirical evidence at a local level-quantitative research conducted on a sample of 500 households in Lower Silesia region in Poland. The research’s ﬁrst objective is to build the original author’s methodology on which the shift patterns from homo oeconomicus (neoclassical economics) to homo sustinens (sustainable economics) may be presented and may be used by scientists worldwide. After preparing a method for identifying concept, the second goal is to identify and describe the new concept of behaviour. The main conclusions are the sustainable behavioural pattern is dominating trend observed among households’ local energy management (homo energeticus). The homo energeticus behaviour was conﬁrmed by every third respondent (critical threshold of 70%) or less restrictive and sustainable behaviour model homo sustinens (critical threshold of 50%) by more than 91.8% of whole respondents.


Introduction
Climate changes stimulated by the increased anthropogenic impact on the environment induce effective propagation and implementation of new methods in energy management. T.R. Burns [1] (p. 1127) indicated the crucial "drivers" of environmental change such as extensive environmental sources consumption, increased garbage, air pollution, biodiversity loss. He outlined the tremendous acceleration in scale and pace of those human impacts last decades and the significance the "sustainability revolution"-sustainalization" that implies the whole society [1] (p. 1128). The sustainability process involves many dimensions: local, regional, national and global scale. Concerns communities, associations, business, federal authorities, policymakers. It reflects human behaviour; attitudes, values change and setting the new rules to follow. It also takes place in science and practice (see Figure 1).
The paper treats the households new concept behaviour that reflects the vital change in local-scale energy management. In light of heterodox economics, particularly behavioural and sustainable economics, philosophy and ethics, premises and determinants may be derived for changes in attitudes, values, motivations and behavioural patterns displayed by individuals concerning energy management and the associated economic decisions. The postulated energy sector transformation and the new (or revised) approach to energy management are construed on the fundament of low-emission, energy-efficient and resource-efficient solutions, including renewable energy sources (RES). The European Green Deal [2] anticipates a growing role of RES solutions as a critical element for improving energy efficiency and effectiveness and limiting greenhouse gas emissions. Furthermore, numerous EU documents [3][4][5][6] emphasise the constant need for devising a new approach to energy management and the dominant role of consumers in the sustainable development of energy systems and energy markets.
The European Union is the world's third-biggest emitter of greenhouse gases, representing around 9% of the global share of CO 2 emissions in 2020 [7]. During EU long-term budget negotiations in December 2020 in Brussels, the EU leaders have just agreed on reducing greenhouse gases by 55% until 2030. This obligation included Poland, the most reluctant country heavily reliant on coal (Poland's coal-fired power stations are among the EU's big polluters). The proportion of fossil fuel sources in power generation needs to diminish to under 20%, and the ratio of RES must rise to about 66% [8].
In the postulated energy transformation context, significant roles are played by local consumers/prosumers of energy. Their access to small-scale installations contributes to an effective increase of energy security and equally effective limitation of carbon emission. The housing stock represents 36% of CO 2 emissions in the EU. Almost half of the Polish households still use poor quality solid fuels for heating, mainly hard coal and firewood (3.5 million are single-family houses). Household solid fuel combustion also concerning 25% of households that heat water that way. This problem is often the financial aspect of energy poverty (low incomes, outdated heating installations, low energy efficiency of the buildings and devices in use) [9,10]. Housing stock also has a significant share of 40% in energy consumption [11].
Local grassroots initiatives have the power of stimulating broader response at a national or even global level. Therefore, the findings of this study apply to households in the Lower Silesia region of Poland. It may be essential to mention that Wroclaw, the region's capital, scored the world's third most polluted city on 13 December 2020, and 3 March 2021 [12]. Low emission indicators do not change much in Poland during the last decade and are still very high [13]. Figure 2 shows relative reductions of the premature deaths attributed to exposure to PM 2. 5 . In Poland, the drops are the lowest in the EU in 2018 compared to 2009 [14]. National energy management in Poland is still predominantly based on hard coal and lignite [15,16]. Wroclaw is also the fastest developing city in the EU [17], so there is a chance to see how the behaviour patterns change in the local energy management. For this reason, scientific evaluations applying to energy transformation processes are of utmost importance. The last decade shows consumers are increasingly more involved in those attitudes and behaviours emphasising [18]: • preservation of present and future generations, • inter-and intra-generational equity, • reduction of climate changes and natural degradation, • quality improvement of the natural environment, • and rational management of energy, resources and energy efficiency.
At the same time, apart from transformations in national and global economies, there are significant shifts taking place in science, involving gradual departure from the Cartesian paradigm of neoclassical economics towards the new paradigm of sustainable development [1,[34][35][36][37][38]. Many economists emphasise the emergence of a new approach to energy management-pro-environmental management developed within the conceptual framework of the economics of sustainable development (ESD) [39][40][41][42]. Still, empirical findings have not adequately documented this hypothesis.
Many economists emphasise the emergence of a new approach to energy managementpro-environmental management developed within the conceptual framework of the economics of sustainable development (ESD) [39][40][41][42], but this hypothesis has not yet been properly documented by empirical findings. Therefore, this author's primary stimulus for the original identification of the research gap was related to the need for a shift in behavioural patterns of households from ego-centred consumption (homo oeconomicus) towards sustainable energy management (homo sustinens to homo energeticus). In accord with the postulates of M. Blaug [43], economic models should be construed on fundaments derived from real and observable economic phenomena and serve to forecast future occurrences of such phenomena. Therefore, a new concept of an individual actively involved in energy management is indispensable for evaluating the modern framework of energy management, particularly the RES segment, as an important element in the postulated implementation of sustainable development.
To fill the research gap, the Author formulated two hypotheses and two main objectives. The first objective was to build a method for the identification of the behaviour concept functioning in neoclassical economics (homo oeconomicus) and the economics of sustainable development (homo sustinens); the second objective: identification and description of the new concept of behaviour involved in energy management processes on a local scale-the concept of homo energeticus. The description of the new behavioural concept (homo energeticus) involves demographics, energy management: energy efficiency, sources of heating and power supply, renewable energy sources management and natural environment attitude. The identification concerns properties displayed by the homo energeticus segment.
They were two research hypotheses formulated: Hypothesis 1 (H1). More households are found to qualify under the homo sustinens than homo oeconomicus concept.

Hypothesis 2 (H2).
Sustainable behavioural pattern is dominating trend observed among homo sustinens local energy management and can be called homo energeticus.
The paper represents the research school of sustainable economics as a new discipline of science within the broader area of heterodox economics. The paper's original input in energy management is expressed in cognitive, methodological and practical aspects. The new local, sustainable behaviour model was created, tested and proved on 500 homeowners living in the Lower Silesia region in Poland. The PAPI method was employed, with results processed using the IBM SPSS statistical software package (methods of non-parametric Mann-Whitney U-test and chi-square tests of independence). With the critical threshold of 70%, it was proved that a third of the studied homeowners in the Lower Silesia region had displayed characteristics typical for the homo energeticus concept. If we lower the critical threshold to a value of 50%, the number of entities conformant with properties of this concept shall increase up to 92% for households.
The concept of homo energeticus based on empirical studies provides evidence of change (or propensity to change) in energy management patterns. Proving the existence of new behavioural patterns could be the incentive to stimulate policymakers to support local RES investments and to meet the EU CO 2 emissions goals.
The article is organised in the following sections: Section 2.1 literature review of homo concepts in economics, which shows the path for the emergence of a new idea of an economic man involved in energy management, Section 2.2 methodology of the survey and Section 2.3 methods of behavioural model construction, Section 3: Study results which provide arguments to confirm the emergent trend in homeowners' approach to the economic management of energy-related issues (homo energticus households number, demographics, survey responses) and properties displayed by homo energeticus segment, Section 4 discussion-including future research and research limitations and finally Section 5: The conclusions.

Literature Review of Homo Concepts in Economics
The paradigms of classical and neoclassical economics were founded on the homo oeconomicus concept [44]. Homo oeconomicus is (and has always been) a notion raising many controversies [45]. The concept is presently refuted by many economic disciplines [46][47][48], including the ESD, as incompatible with the present economic, environmental and social problems, particularly with the operationalisation needs of the SD idea. Over the years, different approaches to the economic man were developed to correspond with specific requirements of assorted disciplines of science. Various economic schools display different approaches to the idea of human nature [49], with practical concepts simplified over throughout numerous abstract analyses of complex social and economic phenomena, in line with methodological requirements of modelling processes. These concepts were also strongly influenced by scientific paradigms adopted in a given field and reflected in economic models (homo sociologicus, homo psychologicus, homo politicus, homo corporativus, homo humanistic economicus, homo social economicus, homo socio-economicus homo satisfaciendus) [50][51][52][53][54].
The most popular concepts characteristic of the SD approach took into account the psychosocial determinants of behaviour and emphasised the variety of value systems associated with market choices. However, those concepts seem to contradict the idea of rational choice dictated by self-interest, including the following: homo oecologicus, homo empaticus, homo cooperativus or homo politicus.
One of the most popular ESD concepts is the homo sustinens model, originally postulated by B. Siebenhüner, an environmental economist at Martin Luther University in Halle (Germany). This concept emphasises the universal character of altruistic, cooperative behaviours (confirmed by evolutional biology), which seems to be in stark contradiction to the neoclassical theory of collective action by M. Olson. B. Siebenhüner utilised the findings of other disciplines, including social psychology, paleoanthropology, evolutional biology and neurobiology, with their hard evidence of universal attention and responsibility for future generations and formation of emotional attitudes towards the natural environment. His view was that the postulated concept stems from cultural and genetic determinants of human behaviour.
Thus, effective identification and provision of empirical evidence for the emergence of a new concept of an economic man involved in energy management within the framework of ESD should be based on a matrix of the homo sustinens model, designed on the basis of psychological and neurobiological determinants of human behaviours [55].

Methodology of the Survey
In order to fill the research gap, empirical research was designed and performed following statistical methodology and techniques [56,57].
The research sample consisted of 500 households in detached and terraced dwelling houses located in the Lower Silesia region in south-western Poland. Survey studies were conducted through personal face to face direct interviews using PAPI (Pen-and-Paper Personal Interview) method, held in April and May 2016. Interviews were addressed solely to adult respondents, declaring as providers of funds for household expenses. The sampling frame was established on the basis of the Lower Silesia address base, with addresses selected at random to serve as departure points for each round of the survey procedure. The selection of samples was based on the random route method. Surveys were held in every third detached or terraced dwelling along the route. Refusals to participate were duly annexed in survey documents and substituted by the next qualifiable dwelling. At street ends, survey interviewers were asked to take a right turn if possible (if not, they took the left turn). Random sampling was used and applied to reflect each of the pre-established spatial layers (territorial zones). The layering was defined to embrace three such layers: parishes/districts of municipal, rural and mixed character (see Table 1). The survey return rate was at 100%. The maximum admissible error for the estimated fraction (d error) was established at 4.38%, with confidence level at p = 0.95, confidence interval α in the range of 0.05 and with statistical value z = 1.96 (see Table 2). The findings were processed using the nonparametric Mann-Whitney U test and the chi-square test of independence. The novel concept of behaviours was established on the basis of this author's matrix for the identification of practical energy management approaches on a local scale. The study was financed from research project support funds by the Polish National Science Centre.

Methodology of Behavioural Model Construction
Basing on the literature review of homo concepts in economics, the author has defined the following properties and traits of energy management as relevant for the homo sustinens concept: • a long-term approach to planning and decision-making, with full observance of social interests and benefits, even at the cost of additional financial expenses, • collective approach to decision-making processes (strongly influenced by external stimuli), relevant to their immediate settings, • propensity to cooperate, • distinct inclusion of elements of immaterial motivation in their decision-making processes, • motivation by external stimuli accompanied by internal motivation stimuli, • full recognition of interests of future generations, highly emotional attitude towards the natural environment, • responsibility for environmental sustenance in practical realisations of economic decisions, • strong preference for environmental protection factors as fundaments of their consumer choices.
The concept of homo sustinens was construed on properties typically regarded as desirable for an economising man operating in the context of sustainable development economics. These properties reflect three distinct dimensions of sustainable development: economic, social and environmental. Decisions are not made independently by individuals-they are founded on opinions from other economic entities.
The author also defined the following properties and traits of households' energy management approaches as relevant for the homo oeconomicus concept: • provisional, short-term approach to planning and decision-making, • the individualised approach to economic decisions, independent from external influence, • placing own economic benefits before other concerns of social/communal interest, such as preservation of the natural environment, • distinct preference for economic factors as fundaments of choices made concerning energy consumption and/or production: pricing, profitability, earnings, subsidisation, funding, investment payback period. Table 3 presents practical realisations of the qualification method for two studied concepts: homo oeconomicus and homo sustinens. Each studied concept was then ascribed by specific queries, complete with the determination of anticipated responses. Scores were assigned to positive and negative responses, depending on the wording of queries. Decided answers received the highest scores (4 pts). Guarded responses (signified by the attribute of 'rather': I rather agree/disagree) received a lower score (3 pts). The remaining answers in a given set received no score. Maximum scores (in pts) were then calculated for each of the studied concepts. For the homo oeconomicus concept, the maximum score was at 60 pts, with 15 queries asked. For homo sustinens, the maximum score was at 68 pts, with 17 queries asked. All multiple-choice queries were four scale intensity: "I definitively agree", "I rather agree", "I definitively disagree", "I rather disagree" and had a form of statements (see Table 3). Each respondent could choose to what extent he or she agree or disagree with the particular statement. Those specific homo qualification statements were mixed and asked with other questions in the questionnaire (together 33 plus 6 demographics questions). The other ways to avoid bias participation were discussed in Section 3. Results limitations. The research sample consisted of 500 households which were the basis of the qualification method for homo oeconomicus and homo sustinens model. Table 3. Qualification method for homo oeconomicus and homo sustinens model.

Points for Responses Homo Oeconomicus Homo Sustinens
Positive responses: "I definitively agree"-4 pts "I rather agree"-3 pts The remaining answers-0 pts: "I definitively disagree", "I rather disagree" I prefer economic factors as fundaments of choices made concerning energy consumption and/or production: (a) investment payback period (b) profitability (c) pricing (d) prosumer earnings (e) pricing is more important to me than energy efficiency (f) subsidisation. Positive responses: "I definitively agree"-4 pts "I rather agree"-3 pts The remaining answers-0 pts (a) I place my economic benefits before others concerns of social/communal interest, such as preservation of natural environment (b) I will invest in fossil fuel sources rather than green ones to get better financial returns (c) I prefer a short-term approach to the planning and decision-making process.
(a) When I invest in RES, I feel that I contribute to air quality improvement (b) I feel responsible for the natural environment condition in my commune/district (c) I do care for future generations to live in a clean natural environment (d) Clean natural environment is a priority in my the decision-making process, benefits and financial costs play less critical role (e) I want to cooperate to make the natural environment cleaner.
Positive responses: "I definitively agree"-4 pts "I rather agree"-3 pts The remaining answers-0 pts Negative responses (homo oeconomicus only): "I definitively disagree"-4 pts "I rather disagree"-3 pts The remaining answers-0 pts Positive responses (homo sustinens only): "I definitively agree"-4 pts "I rather agree"-3 pts The remaining answers-0 pts I am willing to pay more for energy consumption bills if the extra cost would serve to support investment in local RES production facilities taken with the purpose of improving the reliability of supply or/and quality of breathable air on a local scale.
I am willing to pay more for energy consumption bills if the extra cost would serve to support investment in local RES production facilities taken with the purpose of improving the reliability of supply or/and quality of breathable air on a local scale.
Eligibility for the homo energeticus concept category was based on subjective preestablished critical percentage threshold. The number of respondents was qualified under each of the studied concepts, based on a pre-established critical percentage threshold, in 10pp (percentage point) increments, from 50% up to 100%. For example, a critical percentage threshold value of 50% should be interpreted as follows: the respondent qualifies under a given concept if his score reaches 50% of the maximum score value available for answers to questions related to this concept. For the homo sustinens concept, the critical percentage threshold value was set at 34 pts; for homo oeconomicus, the threshold was set at 30 pts. The author discusses the limitations of methodology in Section 4.1 of the article.

The Number of Homo Energticus Households
As mentioned in the methodology section, a suitable critical percentage threshold should be set at a minimum of 70%. As seen in Figure 3, there was also an ostensive difference between population counts of respondents qualifying under homo oeconomicus and homo sustinens concepts, hugely in favour of the latter category. The higher the critical percentage threshold value, the steeper were the qualifying requirements for the category in question. For the threshold value of 50%, as many as 459 (91.8%) of households (out of the total 500 responses), were found to qualify under the homo sustinens concept. For homo oeconomicus at the same critical threshold value, only 52 respondents were found eligible. At a critical threshold of 60%, 67.6% of all respondents displayed strong properties of the homo sustinens category, while a mere 1% represented homo oeconomicus properties. With such a high critical threshold value of 70%, only one respondent was found to qualify for the homo oeconomicus category. On the other hand, the same threshold value revealed 150 households as eligible for the homo sustinens category. A separate examination was conducted to identify respondents belonging to more than one category (concept), but no such cases were revealed.
Study results provide arguments to confirm the emergent trend in homeowners' approach to the economic management of energy-related issues. This can be seen as an impulse to introduce a new concept (category) of an energy-conscious individual, displaying many properties of the previous concept of homo sustinens. In relation to the research area covered by this paper, i.e., energy management, the newly found concept received a label of homo energeticus.
The homo energeticus group was identified using a critical percentage threshold value of 70% of homo sustinens responses. Homo energeticus was observed 150 households (out of the total of 500 collected responses), representing 30% of the studied population. Thus formed, the homo energeticus category was then subject to analytical evaluation to reveal this segment's most characteristic properties and behaviours.

Demographics
Based on responses in the demographics section of the survey, population characteristics of the homo energeticus segment of households were analysed (see Table 4). There were six questions asked: two were open response (age and type of household) and, four were single selection. Women represented 60% of the group (90 female respondents), with men constituting the remaining 40% (60 male respondents). Eight persons (5.3%) declared having a basic level of education, with further 54 respondents (36%) disclosing vocational-level education. Secondary education was declared by 60 respondents (40%), and higher education-by 28 respondents (18.7%).  30 20 Age analysis of the above segment (the homo energeticus category) revealed three persons in the age group of 18-24 (2%), and 22 respondents between 25-34 years of age (14.6%). Age groups 35-44 and 45-54 were each represented by 27 respondents (18%). The most populated age group was that of 55-64 (39 respondents, i.e., 26%). In this case, 32 respondents (21.3%) placed in the age group of 65 and older.

Survey Responses from the Homo Energeticus Segment
Households were examined for solutions employed for central heating and usable water heating, power supply and energy efficiency (questions with one or more than one possible answer). Out of the entire research sample of 500 households, 26 respondents declared their houses to be energy efficient. A large part of these (as much as 16) belonged to the homo energeticus segment. For the survey, it was assumed that energy effectiveness was applicable for households with heating energy consumption (UE-usable energy for central heating, water heating and ventilation purposes) in the range of 31 to 70 [kWh/m 2 × year]. Respondents were invited to consult their energy supply slips to verify their assessments.
As many as 87 respondents out of the entire 150 population qualified under the homo energeticus segment (58%) had their walls insulated, with 69 more having insulated roofs or attics. In addition, most of the respondents (145 of all 150) had their windows insulated.
The argument of increasing the energy efficiency of their house in choices involving the use of energy sources was evoked by nearly 100% of the homo energeticus segment (149 households). Similar findings were obtained for the argument of increasing the reliability of energy supply (148 households). A slightly lower emphasis on the use of local (e.g., municipal) energy sources was stated by 146 households. In this case, 144 households, (i.e., 96%) pointed to the argument of increasing local security of energy supply.
As many as 100 respondents out of the entire 150 population qualified under the homo energeticus segment utilised firewood as a source of energy (see Figure 4). One household used wood pellets/chips for house and water heating. One other household used an air heat pump solution for house heating. Solar collectors were used in two households for usable water heating. One household used a solar collector to power its underfloor heating system. The survey revealed that none of the households had employed any solution whatsoever based on renewable power supply sources. Coal was used for central heating purposes by 81 households (54%) and as a source of usable water heating by 76 households (50.6%). Within the coal-utilising households, nearly every respondent (79) considered their central heating apparatus to be in good working condition. Two respondents displayed some reservations in this respect, subscribing to the 'sufficient' response. One respondent used a coal-burning furnace, and another household used coal-fuelled tiled stoves for room heating. However, only 22 of all coal-consuming households had been equipped with modern apparatuses of less than eight years of active service (installed between 2011 and 2018). This means that the remaining 59 households (nearly 40% of the homo energeticus segment) will soon face the need of modernising their heating systems. This group may show interest in replacing them with a more efficient low-energy and low-emission system (see Figure 4).
Eight households used eco-pea coal for central heating and usable water heating, with three more households using coke-burned systems for the same purposes. The gas supply network was a source of house and water heating for 38 representatives of the homo energeticus segment. One household used electric power as a source of house and water heating. Communal heating services were used by two households.
The study aimed to define the homo energeticus approach to RES management, so analyses were made of declared behaviours in the studied area. Queries were designed to assess the potential demand for RES installations, willingness to participate in RES installation costs, improvement of breathable air quality on a local scale, limiting the risk of a power outage, aspiration to become a prosumer, prospect of benefits offered by RES, the level of RES knowledge and household motivations for decisions related to energy management.
Many interesting conclusions can be drawn in relation to the general level of RES knowledge. Suppose we contrast the results from the entire studied population of 500 against the findings obtained in the homo energeticus segment. In that case, we may find that there are no significant differences between the two populations in each query category (single selection questions). In both groups, the level of knowledge is similar in each of the examined categories. More than 65% of respondents in both groups selected an answer associated with the poorest knowledge of RES. Only 15% of respondents in both groups displayed general knowledge of basic types of RES installations (solar or wind powered generators). These findings confirm the general lack of knowledge and attest to poor education on the subject of RES. Considering the fact that the subject has recently gained public recognition in mass media, practical knowledge of the subject among households should be much higher.
Reasons for the poor knowledge of RES may be derived from the next query, with the following phrasing: "Please provide examples of parish/district support for the public in relation to RES". Six variants of answers were provided, with a space to add their reply. Respondents could point to more than one answer (multi-select questions). In this case, 26 respondents brought up the context of local advisory centres and consultation services (nearly 18%). Here, 35 answers (23.8%) emphasised the dissemination of information on parish/district websites, 37 responses (25%) chose to emphasise leaflets, eight more (5.4%) subscribed to the answer related to local support in RES subsidy submissions. Only two respondents brought up the argument of formal meetings with potential investors, and only one respondent chose to emphasise training. Concluding either the respondents are not adequately informed of the available forms of education or that such education is not adequately provided (see Figure 5). Despite their declared lack of knowledge on RES, representatives of the homo energeticus segment were fairly accurate in identifying environmental benefits offered by RES solutions. In this context, four queries were construed to study the accuracy of respondents' assertions of benefits from the use of RES. All the homo energeticus segment representatives were confident that RES investments contribute to the quality improvement of local breathable air. Nearly all of them (98.6% and 94.6%, respectively) provided positive answers to the following statements: "the use of RES has a positive effect on security and stability of energy supply" and "the environmental and climate policies of the EU are based on support for RES development". Those statements were presented with four scale intensity: "I definitively agree", "I rather agree", "I definitively disagree", "I rather disagree", mix with homo concept identification queries.
Similar findings were obtained in another query, where respondents were asked to weigh the benefits borne by the introduction of RES. Environmental benefits came first on the list-clean air and improved condition of the natural environment was emphasised by 86 respondents, followed by the prospect of savings on energy/fuel expenses (56 responses) and by the argument of preserving fossil fuels for future generations (41 responses).
"Do you believe that the increased use of RES will bring increased economic benefits, or do you feel that it will only add to the existing cost?"-this was the next item on the list of queries (single selection option in each statement). The counts of responses in favour of costs and those emphasising benefits were fairly similar concerning costs and benefits for companies, farms and households. Distinct differences were observed, however, in relation to evaluations made by representatives of mixed (rural-municipal) areas, where 77 respondents saw benefits, while 41 were more inclined to emphasise extra costs. A similar structure was observed on the general population level: 74 respondents accentuated benefits, while 46 of the homo energeticus segment emphasised the costs. Ca. one -fifth of the homo energeticus segment chose the answer of "difficult to tell" for each of the studied categories (general population, farms, households, companies, district and city).
Homo energeticus were fairly accurate in their assessment of economic and social phenomena influenced by the introduction of RES (single selection option in each statement). As many as 120 respondents (80%) pointed out the argument of improving the living standard and quality of life (e.g., the use of locally available energy sources, security of energy supply on a national level). In addition, 144 respondents (96%) subscribed to the view of health benefits (quality of breathable air and the natural environment). In this case, 130 responses (86.6%) emphasised the reduction of CO 2 and other hothouse emissions in various sectors of the national economy (farming, energy production, transportation); 122 respondents chose the answer related to energy savings (81.3%). However, respondents were also largely oblivious to the fact that RES may stimulate the increase of employment or revenues in rural areas. Some of them were even quite convinced that the effect would be the opposite. Less than 50% were adamant that the introduction of RES would improve the development potential of the farming industry.
Homo energeticus were also fairly consistent in their view of activities deemed necessary to propagate the RES idea among households. From 120 to 130 respondents (i.e., between 80% and 86.6%) were able to identify all of the postulated activities (multiselection option in each statement). Homo energeticus are aware of the need for local-scale professional advisory support in matters related to the impact of RES on the natural environment, generation technologies, sources of financing and subsidising of RES investments, appreciation of the tangible benefits for households resulting from the use of RES and propagation of education and knowledge of RES.
Respondents also emphasised barriers of a bureaucratic character: requirements associated with documentation and formal permits (67%) or complexity of regulations (63.3%). The persistence of such perceptions may be one of the reasons behind the revealed reservations to fund RES solutions out of household expenses.
Queries related to the use of power sources for house heating, water heating, and power supply revealed that very few analysed households had access to RES. In light of the above, further investigations were made to reveal households with access to such systems (pending installation) as well as those willing to consider such investment (see Figure 6). Such investments were already made in four additional households and nearing completion (2.7% of the homo energeticus segment). Six more households had RES plans already in place (4%), and further 28 households displayed interest in making a RES investment (nearly 19% of the homo energeticus segment). As many as 112 households (nearly 75%) had no such plans and displayed no interest in pursuing the idea. Of the four households with investments already underway, three chose to use solar collectors and one invested in an evacuated tube collector solution. Five of the households with plans to invest in RES were interested in solar collectors; one was inclined to invest in a heat pump solution. Among the 28 households displaying initial interest in RES, three were in favour of a heat pump, one-a wind-powered generator, and four were inclined to consider photovoltaic solutions. Thus, as many as 27 households displayed initial interest in solar collectors. It must be noted that respondents were allowed to select more than one answer to this query. Respondents were also asked to present an acceptable cost they would be willing to carry out of their expenses to introduce renewable energy sources for their household needs (see Table 5 and Figure 7). Households were asked to suggest their answer. In this case, 27 (18%) representatives of the homo energeticus concept were willing to carry such a cost (by presenting a non-zero value in response). In comparison, only 24 persons outside the homo energeticus segment (6.9%) were willing to invest in RES, with as many as 110 respondents refusing to carry such a burden. It may be worth noting that the query was construed to verify some of the previous responses. The findings revealed that the number of persons declaring their interest in RES (28) is nearly equal to that of persons willing to carry the cost of a RES investment for their household (27). Table 5. The volume of own expenses for RES introduction: the comparison of responses from the entire studied population and homo energeticus.

Own Expenses for RES Introduction [PLN]
General Population Homo Energeticus State subsidies and other incentives may influence future interest in RES investment. Respondents were asked to provide an estimated percentage of such support they would be willing to consider as an adequate incentive to purchase a RES solution for their household (open response question). The most prevalent answers fluctuated in the range of 50% to 70% (represented by 63% of answers), and higher percentages between 70% and 100% were provided by further 48 respondents (32.6%).
None of the respondents was willing to invest in RES production for gainful purposes (represented by the prosumer attitude of selling surplus power to the national grid (single selection question: "positive"; "rather positive"; "rather negative"; "negative"; "difficult to tell"). "Rather positive" answers were given only by 9 out of the total 150 households classified as homo energeticus (6%). However, three out of the nine respondents were unwilling to invest in RES out of their expenses. Therefore, their declarations should be seen as dubious.
Another query addressed specifically the volume of own expenses that respondents would be willing to invest in a RES installation for gainful purposes (see Table 6 and Figure 8). Respondents were asked to suggest their answer. Six persons (4%) provided a non-zero answer, meaning that as many as 144 respondents responded zero. By comparison, responses from the entire studied population of 500 revealed 27 non-zero answers to this query (5.4%). It is worth noted that homo energeticus had declared their potential investment contribution at a minimum level of PLN 1000 (around 400 euro), with the prevalent answer of PLN 2000 (about 800 euro). At the same time, the remaining segment declared a much lower contribution, from PLN 100 to the most prevalent answer of PLN 1000 (10 responses) and one response with a curiously confident value of PLN 1100 (around 440 euro). Table 6. The volume of own expenses: the comparison of responses from the entire studied population and homo energeticus.

Own Expenses for Gainful Purposes [PLN]
General The last query associated with the declared volume of investment in RES was related to the contribution in communal energy cooperatives providing power or heat generation on a local scale (close-ended query). Here, only eight respondents showed interest in such a solution, with negative answers from 142 respondents.
The study also examined the percentage share of homo energeticus willing to pay more for their energy consumption if the extra cost would support investment in local RES production facilities to improve the reliability of supply or/and quality of breathable air on a local scale. Only one respondent was willing to increase their contribution. "Rather affirmative" answers were provided by 11 respondents. In this case, 12 households (8%) were potentially willing to pursue such a solution.

Statistical Differences between Behaviours Displayed by Homo Energeticus and Those Observed in the Remaining Household Segments
Statistical tests were conducted for the analysed households using IBM SPSS statistical software suite to understand better properties and behaviours displayed by homo energeticus. A chi-square test of independence was conducted to analyse differences in responses provided by homo energeticus against those collected from other respondent segments in the statistics segment of the questionnaire. In terms of such qualities as age, district/parish location, gender, number of household members and income, no significant differences were found between homo energeticus and other segments. For example, the homo energeticus group was characterised by a 60% of female representation compared to a 55% representation outside the segment, attesting that the difference is not statistically significant.
A non-parametric Mann-Whitney U test was used to analyse differences in perception of the quality of natural environment between homo energeticus and the rest of the respondents. Differences were found in responses to the following question: "How would you describe the air pollution in your district/parish?". The test involved ranking variants of the dependent variable (from the highest to the lowest) between studied segments. The condition of equipotency between groups was not met, so this particular method was selected. As mentioned before, the respondents were divided into two segments, with a critical percentage threshold value of 70% adopted as the basis of distribution between segments. In effect, the homo energeticus segment proved less populated. The more negative was the revealed perception of local air quality, the higher score was attributed. The minimum score was attributed to responses "Very low pollution" and maximum-to "Very high pollution" responses. The remaining variants were: "Low pollution", "Pollution is neither low nor high" and "High pollution". Persons choosing not to answer and those unable to express their view in the matter were not taken into consideration. Calculations were made using the SPSS statistical software suite. According to the findings, members of the homo energeticus segment presented more negative perceptions of local air quality (M = 3.63) compared to those in the remaining segment (M = 3.35) and the difference was evaluated as statistically significant, with U = 20,443, and p < 0.011.
The second query showing a statistically significant difference between the homo energeticus segment and the remaining group of the studied population was phrased as follows: "Please give an estimated cost you would be willing to cover out of your own expenses to purchase an energy installation based on renewable energy sources to cover for your household energy needs?". Homo energeticus segment was found to declare higher levels of such contribution (M = PLN 1722) compared to the remaining respondents (M = PLN 357). This difference is statistically significant, with U = 18,437 and p < 0.001. This difference was also examined using the Mann-Whitney U test. Since respondents declared sums of their contributions in RES investment, their answers were adopted as a dependent variable. Calculations were made using the SPSS statistical software suite. Of all the 150 representatives of the homo energeticus segment, 27 respondents (18%) chose to declare a non-zero sum. The phrasing was intentionally presented as an open response question to avoid the suggestion effect.
No statistically significant differences were found between representatives of the homo energeticus segment and the remaining group in their responses to the following: "Please give an estimated sum you would be willing to invest in a RES installation for gainful purposes?" (open response question). In this case, six respondents from the homo energeticus segment (4%) declared a non-zero sum. In total, for all 500 households examined in the Lower Silesia region, only 27 (5.4%) chose to declare a non-zero sum. Thus, interest in this solution was fairly low.

Properties Displayed by the Homo Energeticus Segment
To identify the dominant behavioural properties displayed by homo energeticus, analyses were made of responses to those queries, which served as the basis for classification of respondents to the homo sustinens concept (see Table 3). Table 7 presents statistics and percentages of responses in this category. Responses were aggregated in the manner employed for the category qualification stage. The most desirable responses were strong confirmations ("I strongly agree") and guarded confirmations "I rather agree". Table 7. Aggregate statistics and percentages of responses provided by homo energeticus.

The Type of Responses Homo Energeticus Answers Number of Responses Percentages of Responses in the Category
Positive responses: "I definitively agree" "I rather agree" Positive responses: "I definitively agree" "I rather agree" I am willing to pay more for energy consumption bills if the extra cost would serve to support investment in local RES production facilities taken with the purpose of improving the reliability of supply or/and quality of breathable air on a local scale.
12 8% Table 7 serves to illustrate percentages of responses gathered from the survey. Of all 17 queries considered, 12 received positive responses. Those 12 positive question responses constitute more than 90% of the studied segment. This means that more than 70% of respondents in the homo energeticus segment display such dominant properties as: genuine concern for the natural environment and a sense of environmental responsibility formed independently of opinions expressed by others, desire to improve the quality of natural resources, consideration for future generations, cooperation with family members, partners and (less frequently) neighbours in making decisions associated with energy management. Furthermore, homo energeticus freely declare their readiness to cooperate with others to improve the natural environment on a local scale. With respect to RES use, all homo energeticus (100% of those classified as homo sustinens) declare that the environmental benefits of RES are of great importance to them. In addition, all homo energeticus believe that, they contribute to the effective improvement of breathable air quality by investing in RES solutions.
Only 37 of those classified as homo energeticus chose a positive response to the query phrased as follows: "I am inclined to keep a short-term perspective, I rarely think about the future". Their answer may suggest that the majority of the segment displays a more rational approach of long-term planning.
Another fairly dominant property displayed by respondents classified under the homo sustinens concept was associated with priority placed on the quality of the natural environment as a fundament of their investment decisions, with other benefits (including those of financial character) deemed of lesser importance. This response was attested by 78.6% of homo energeticus.
More than 52% of the homo energeticus under study declare being motivated by non-material factors. A third of the studied population get involved in environmental issues only when others display a similar attitude (36.6% of respondents). Eight percent of the studied group declare their willingness to pay additional energy expenses if the surplus is invested in developing of local RES solutions, as these will improve the quality of local air and limit the incidence of power shortages.
Queries related to financial and environmental motivation in decisions regarding energy management were verified through questions with multi-variant responses. Two thirds of the studied population revealed their tendency to place own economic interest before the environmental concern for a clean environment (100 responses), with the remaining third providing a negative answer. A firm 78.6% (118) of respondents gave priority to environmental concerns as prime movers of their investment decisions, with financial and economic benefits placed lower on the ranking. At the same time, the phrasing of "I would consider investing in black (non-environmental) sources of energy if it gave a promise of increased economic benefit compared to a green solution" found confirmation from only six respondents. This statement was refuted by as many as 144 respondents (96%), with nearly a half of them choosing a decidedly negative answer. The findings suggest that the quality of natural environment is essential for homo energeticus. However, the financial benefits are also of value and are evoked almost as frequently as those of the environmental character.

Discussion
It was demonstrated that processes associated with local energy management in households are dominated by motives and purposes characteristic of the concept of homo sustinens and fitting with the paradigm of sustainable development, but-at the same timetransgressing the canonical definition of the concept of homo oeconomicus. With critical threshold value of 50% as many as 91.8% of households were found to qualify under the homo sustinens concept and only 10.4% under homo oeconomicus concept (see Figure 3). Study results also confirmed homo energeticus displayed strong, sustainable properties of the homo sustinens category. Many properties meet even 100 percentages of responses in the category (see Table 7).
Two research hypotheses were validated in light of the above, and the two initial research objectives posed. The homo energeticus segment was defined based on scoring 70% of the adopted critical percentage threshold value of homo sustinens responses. Identification and empirical verification of the concept of homo energeticus as the most characteristic in the context of energy management is a significant contribution to the economics of sustainable development. The paper fills a research gap in the area of heterodox economics, economics of sustainable development. The article also indicates and provides evidence of change (or propensity to change) in management patterns from homo economicus demonstreted in classical economics to homo sustinens and at a local level, to homo energeticus in the area of energy management.
The homo energeticus approach to energy management on a local scale was confirmed by a steady representation of one in every three respondents. This segment may be characterised as follows. No statistically significant differences were found to differentiate the homo energeticus segment from the rest of the studied population of 500 households in the Lower Silesia region of Poland for such properties as: number of household members, household revenues, age, gender, level of education and location (municipal, rural, mixed). In addition, most of homo energeticus households were characterised by a long-perspective approach to planning, in line with the definition of sustainable development. Homo energeticus representatives are more inclined to present pro-environmental behaviours and perceive the natural environment as more polluted and distressed than the remaining segment. Even though a clean environment is very important for homo energeticus, a marked share of 85% of the segment confirmed that financial arguments are of roughly equal importance to the main decision-making scenarios. They expressed it in such terms as: pricing, sizeable public co-financing support, the payback period and profitability of investment. Less than 30% of respondents selected the answer, suggesting that the price of systems is more important than the promise of energy saving potential. In addition, homo energeticus were also more inclined to declare larger sums of their potential investment in RES solutions for their household needs compared to the remaining segment. At the same time, 96% of respondents from the studied household were not inclined to invest in black energy, even if it promised a sizeably better financial return for them compared with green energy solutions.
Homo energeticus place emphasis on providing their households with energy saving solutions. Such responses were collected from 61% of those respondents declaring that their homes were already energy efficient. Nearly all of the studied households had their windows replaced by modern insulated systems. One in every two of the homo energeticus representatives used coal to fuel their heating systems or usable water heating systems, with nearly 40% of them utilising systems older than eight years. It may be seen as suggestive of the imminent prospect of replacing them with new energy production systems. However, the popularity of RES among homo energeticus, while considerably higher than the rest of the studied population, was still relatively low. The most important factor to hamper such investment was associated with the perception of legal and financial barriers for Poland's developments. The greatest hope for an effective increase of RES investments among households can be found in the fact that one in every five respondents was appealed by RES investment and ready to make their financial commitments to that effect out of their own expenses. RES investments were considered attractive if supported by 50% volume of public co-financing. The study revealed that RES installations were already used in less than 10% of the studied households.
Questionable responses were gathered in relation to public environmental awareness and social education. On the one hand, the findings suggest an adequate level of RES solutions knowledge, on the other-low interest in expanding this type of knowledge. Nearly 70% of households admitted to having gained some knowledge of RES but were not inclined to pursue such knowledge actively. Only one in every five studied households was aware of the wealth of environmental and RES education programmes offered in their district/parish. On the other hand, more than 90% of the homo energeticus segment were found to be aware of the benefits offered by RES in terms of populational health, breathable air quality, security and reliability of energy supply and economic gain (as a potential source of gainful profit).
Analyses of correlations suggest that persons already in possession of RES solution as well as those in the course of such investment, those with plans already in place and those interested in this form of investment received higher scores in the scale of proenvironmental behaviours compared to those not involved in pursuing a RES solution.
Incidentally, this study of homo energeticus behaviour, conducted in 2016, coincided with a national-level survey of energy management organised by CBOS and Collegium Civitas. Their findings suggest that more than 80% or respondents perceived RES as a source characterised by high social acceptance and development perspectives. Compared to the results of the 2015 edition of the survey, support for coal solutions dropped by 10%, while that for RES solutions was at a steady (and high) level [58]. In addition, 89% of respondents were adamant that the use of RES solutions will improve the natural environment quality in Poland and increase the impact of individuals and communities in matters related to energy management on local and national scale. Furthermore, more than 80% of respondents subscribed to the view that water-powered, wind-powered, geothermal and solar generators are climate-friendly and offer a reduction of carbon emission [58]. Respondents were also asked for opinions on the use of RES in the context of the ongoing political dispute on state support for the coal-based national energy policy. On the one hand, CBOS findings suggest high acceptance for the use of RES, in accordance with the EU-wide trends. On the other hand, a sizeable percentage of respondents were in favour of a more effective use of the available fossil resources in Poland.
Nearly 70% of respondents perceived environmental pollution as one of the most dangerous effects of civilisational development. No queries were posed with regard to respondents' perception of the energy efficiency of their houses. The only aspect covered in the quoted report was the use of modern insulated windows, with confirmation received from 84% of Polish respondents; the lowest ratio of buildings with thermal insulation was reported in the Lower Silesia region (54%) [58].
Nearly two thirds of Polish respondents emphasised their perceived importance of the source of their energy supply (conventional vs. renewable). These declarations seem to correlate with the perceived quality of material life conditions. It might be important to note that 52% of respondents would be willing to pay more for their energy needs if it came from a renewable source. The majority of these (and 35% of the total number of respondents) would be willing to accept not more than a 5% rise in energy pricing for a renewable energy source. In total, nearly one in every five respondents was willing to accept a rise of 6% or more for green energy compared to the present burden. It may also be significant that the reported willingness to carry a higher burden was most frequently correlated with the perceived importance of the source of energy supply for households [58]. CBOS reports also provide evidence of a positive correlation between prosumer attitudes and pro-environmental attitudes, expressed by a very strong emphasis on the problem of breathable air pollution and other environmental risks related to carbon emission. Another CBOS survey (January 2016) reports every fifth Pole is willing to generate own electricity from RES [59].
The findings presented in the CBOS report of 2016 seem to correspond well with the findings of this study (for the same year). In particular, both groups of respondents displayed similar levels of their declared interest in RES solutions, their emphasis on protecting the natural environment and their identification of benefits offered by the use of RES. In both the CBOS report and this study of homo energeticus behaviours in a local perspective, one in every five respondents was open to the idea of purchasing a RES source for their household needs. However, comparisons between the two studies should be taken with care, as they adopt different research methodologies and target profiles (nation-wide vs. local perspective). In addition, the interpretation of the findings across both studies provides cursory conclusions, which may only be used as suggestions for further research. Nevertheless, the CBOS findings support a conclusion that the change of behavioural patterns related to energy management is also evident on a national scale. One question remains open: is this change strong enough to elevate the homo energeticus to a rank of the most prevalent pattern in Polish society? tionnaire sections. In this manner, accordance between such related items served to confirm the authenticity of declared behaviour, thus limiting the emergence of purely declarative statements in some of the studied aspects.
There are additional methods to overcome the social bias participation like avoiding double-barreled questions or provide incentives for respondents to answer the questions.
However, the author has implemented all the methods presented to avoid bias participation; other methodological limitations of the presented study and barriers exist. It is worth noting that scientific research is characterised by a large number of questions and usually lasts much longer than, for example, marketing research. A single household interview lasted here about 23 to 35 min. The interviewer tried to assess whether the respondent was bored with the answers. During the training, the interviewers were taught to react when they noticed that the respondent was marking identical answers in subsequent questions. They made sure that the respondent wanted to indicate those answers. Of course, any suggestion from the interviewer should be avoided.
An additional limitation of the presented research is that the behavioural studies contain emotional statements or questions. Therefore, it can be distracting in giving objective answers.
It is worth also mentioning that face-to-face PAPI (Paper and Pen Interviewing) survey, which was implemented in the presented homo concept study, may cause social bias participation because the respondent and interviewer see each other. The respondent might not feel anonymous. However, CATI (Computer Assisted Telephone Interviewing), which might be used instead and increases anonymity, is more challenging to conduct in the case of an extensive questionnaire. There is also a high risk of interrupting the conversation and not completing the interview. Thanks to the personal presence of the interviewer in the PAPI survey, it is possible to explain difficult questions and issues on an ongoing basis during the interview. Direct survey implementation techniques are characterised by the greater inclination of respondents to participate in the survey. In turn, it enables better quality of the obtained data and greater return questionnaire rate. It is worth mentioning that face-to-face interviews can even help avoid some bias participation like acquiescence bias. The interviewer is the one that has control over the interview and can keep the respondent on track to completion and react when respondents give positive answers to all the questions asked. In CATI or CAWI (Computer Assisted Web Interviews) interviews, some respondents do not even bother to read the questions, just choose affirmative answers. In addition, the individual being interviewed is unable to provide false information such as gender or age. Respondent can also indicate a level of enthusiasm for the topics being discussed in the interview. All these features were decisive in choosing the PAPI method, although this method was the most expensive.
Social bias participation may impact the overall validity of the study. If the research methodology is uncertain and the research structure is not well designed, conducted and controlled, the risk of bias participation may be high. Therefore, it can impact the overall validity of the analysis and conclusions. That is why it is essential to pay special attention to the proper preparation of the questionnaire and conduct preliminary research testing. It is also important to select a professional research team and a research company. The research presented in the article was carried out by a reputable company specialising in scientific, social research on the Polish market.
It is hard to expect that the respondents will be able to answer questions without any bias. However, the proper structure of the survey and well-prepared methods to conduct can help the researchers minimise the response bias.

Critical Percentage Threshold
The suitable critical percentage threshold was subjectively set at a minimum of 70% and formulated in a cautious way. That way, the respondents had received no less than 70% of the maximum score value available in relation to the concepts of homo sustinens and homo oeconomicus. The results analysis proved that with the proposed 70% critical threshold, the confirmation of homo sustinens behavioural properties were displayed and obtained even in 90% by homo energeticus (see Table 7). Lowering the critical threshold would result in weaken displayed behavioural properties. Such a steep requirement (70%) was intended to provide greater strength of individual associations with each of the studied concepts. Such a prominently high and rigorous vale was also assumed to provide hard evidence of pro-environmental behaviour in energy management. However, this method is subjective and requires further research to recognise the critical threshold approaches, propose those thresholds and qualify households for homo concepts. The use of fuzzy logic to model human behaviour maybe help investigate the critical threshold approaches and the degree of membership of homo concepts.
Fuzzy logic, a form of many-valued logic, can be used to represent a set of selected human characteristics [60][61][62][63][64]. The values of critical thresholds could change depending on the degree of environmental awareness, patterns of behaviour presented in a given country, progress in the energy transformation, government support, introduced subsidies, incentives, demand and prices of energy and RES substitutes.
Considering the other study limitations, it is worth remembering that the research outcome characterised only a certain community. Therefore, a more expansive scale investigation on a regional or national scale is recommended. Secondly, analysing large sets of different behaviours from different countries seems to be very methodologically complicated. Thirdly, self-reports are usually correlated with actual behaviour, but this is only the correlation, not the natural, observed behaviour, which can differ from declared [65,66].

Future Research
Transformations in the energy segment can be seen on many levels of energy management, from local perspective to the global scale. This author's studies conducted on a local scale suggest a strong pro-environmental shift of energy management attitudes, a trend relatable to the idea of sustainable energy. The studies should be recapitulated on a national scale to evaluate the scale and intensity of such changes in consumer behaviours. It should be followed by an examination of international trends in this respect. As the model presented herein is fully replicable, it may safely be employed for this purpose. However, more tests with other case studies are necessary to improve the overall validation of the model. Future investigations could involve studies of differences in environmental behaviour in energy management between EU societies to establish what common behaviours and the factors causing them. The findings might serve as a basis for building an effective strategy for stimulating the pace of the pro-environmental shift and adjusting its determinants to the identified behavioural patterns of energy consumers.
The state-level energy and environmental policies represent those decision-making areas that directly influence the health, well-being and sense of security of whole societies [67]. The results of sustainable energy management studies may reduce the cost involved in practical implementations of these policies. One of the most important objectives of the national energy policy in Poland is to include (integrate) RES districts elements of the central energy system planning. The Energy Policy of Poland until 2040 [67] emphasises on responsibilities of local self-administration bodies in preparation of local planning assumptions and plans for the provision of heating, energy supply and gas fuel supply. Regulations to this effect have already been introduced in the Energy Law Act [68]. This should be supported by suitable preparations on regional (voivodship) and local level (municipalities, parishes), as a functional element for the realisation of national energy development strategies. Such strategies consider both regional and local availability of energy sources and technical infrastructure, including the renewable sources for power, heat, air conditioning and other associated the production and generation systems-also those related to production of liquid fuels and biogas.
Local investment strategies of districts and energy producers should be correlated and coordinated. Therefore, it is important to support local implementations of the subsidiarity principle as an essential element of the sustainable development idea. The principle holds that all organisational and legislative activities should be pursued at lower levels of authority. This approach provides local bodies with a good degree of independence for effective and efficient elimination of problems, particularly those related to local perspectives of energy supply planning. In effect, communities and individual members are more aware of the fact that their active participation in decision-making processes will have a tangible impact on their health and life quality standards. They may play an active role in constructing local energy policies and can also profit from quality improvements of the natural environment and the associated health benefits. In addition, such solutions offer potential for new jobs or economic gain related to RES generation services. Proper observance of the subsidiarity principle requires effective incorporation of scientific findings and studies of changes in consumer behaviours associated with energy management on a local level, both in the context of political decisions and in public consulting. However, the effective realisation of public consultations conducted in relation to the recent government policy project of energy supply strategy failed to provide opportunities for genuine communication between politicians, decision-makers and local communities. The entire round of public consultations was finished in a month-such a time frame is not sufficient to allow for constructive debates. Both scientific evidence and advisory practice suggest that adequate and reliable communication mechanisms for the presentation and exchange of diverse opinions serve to reduce the incidence of local conflicts and social tensions. With regard to practical implications, policymakers should consider the market signals and the research outcomes, which proved to be interested in RES investment.
When the survey was conducted, the respondents who had RES installed benefited from government funding dedicated to solar collectors. The program lasted only two years. Later, interest in purchasing or extending the sources used decreased (see Figure 6). In the last two years (2019-2021) PV interest increased dramatically due to the introduction of another financing program, this time dedicated to PV investments. Currently, the new law and policy documents plan to introduce several incentives and programs supporting the development of the RES market [9,66,[69][70][71]. These solutions are dedicated to active households who want to increment the resources installed and new active users. Incrementing the renewable energy sources installed will apply to: • hybrid solutions combining various RES technologies (photovoltaic panels, solar collectors, heat pumps for heating and cooling, energy storage, including those integrated with EV, PHEV), • the forms of active energy consumers (virtual prosumers, individual prosumers, citizen energy communities, energy clusters, energy cooperatives).
The Polish energy policy Pillar III. "Good air quality" contains the solutions socalled "Climate Houses/Buildings". This concept aims to increase the energy efficiency for consumers, including households and companies, and enlarge the independence of external supplies of electric power, heat and water. In their buildings, they could hybridise all the resources at their disposal.
The increasing role of the local energy communities and the active participation of end consumers will require V2-X implementation. This technology concerns the flexibility in charging electric car system. V2-X applies to vehicle-to-everything (grid (V2G), home (V2H), building (V2B)). According to V2G car battery can be charged and discharged based on power grid signals. V2H enables to use of electricity from EV battery to your home or building electrical loads. This new technology requires adjusting distribution systems, mainly in the gradual transition of the passive grid (one-way) into an active grid (two-way). It helps to balance variations in energy production and consumption. In addition, the use of V2-X will increase the number of charging points (f.e., homes) and enable energy storage. To ensure the conditions for V2-X development, smart metering and energy management systems implementation is also essential.
Using hybrid solutions combining various RES technologies and EV, PHEV is a considerable step towards self-balance within self-balancing areas. The questionnaire survey did not consider the questions concerning PV or PHEV because the share of EV in the Polish car market is still meagre. However, every third Pole is interested in buying an electric car. Only 20,000 passenger cars were registered in Poland till the end of 2020. Therefore, it just a declared, not observed behaviour, which is different from reality. The lack of market incentives and technical infrastructure still pose considerable barriers to increasing demand. The density of charging points per 100,000 inhabitants varies from 0.89 to 2.99 depending on the province. At the end of April 2021, there were 1456 publicly accessible charging stations for electric vehicles in Poland (2838 points), and a total of 23,834 electric cars were registered in Poland (over 20,000 of them were passenger cars) [72].
New market solutions and incentives concerning RES and electromobility development should be implemented according to Directive (EU) 2019/944 of the European Parliament and of the Council of 5 June 2019 [73]. Such solutions will be introduced in the coming years, starting in 2021.
Using the smart grid system will support the integration of electricity generated by RES. Thus, all actions of users will be connected (prosumers, local energy communities). That is why high hopes are placed on future research concerning the changing the profile of homo sustinens of its electricity consumption (f.e., the interest of becoming active consumers, benefits the respondents can get from distributed energy systems).

Conclusions
In the ESD approach, individual and communal participants in energy management are perceived as operating in a mega-system of society-economy-natural environment. Therefore, they should satisfy their energy needs in such a way as to ensure effective protection of the natural environment by incorporating renewable and alternative sources and technologies of energy generation. Homo energeticus approaches their energy management duties according to the principles of inter-and intra-generational equity, preserving the scarce natural resources and emphasising the quality of the natural environment.
The identified set of properties and behavioural patterns characterising the homo energeticus in relation to local energy management was confirmed in more than 90% of those respondents. The set includes the following characteristics (see Figure 9):

•
Consideration for the needs of present and future generations. • Consideration for the natural environment and willingness to take responsibility for its condition, irrespective of general opinions on the matter. • Emphasis on the use of locally available resources (including the introduction of RES) and the improvement of energy supply security on a local level. • Awareness of the positive pro-environmental effects of RES solutions. • Intention to increase the energy efficiency and reliability of energy supply. • Confidence in improvements in breathable air quality and energy supply security/reliability. • Attitude of cooperation and co-action, with a collective approach to decision-making procedures. • Cooperation on common goals and the ability to place social interest before own profit.
The above set of properties and behavioural patterns was represented in nearly all of the studied households included in the homo energeticus model. Thus, the analysed data and presented results proved observable ecological, behavioural patterns related to energy management. The conclusions of scientific examinations may be effective in stimulating the implementation of the energy transition in Poland. The pro-ecological behavioural trend could be reinforced by the effective implementation of the proposed support mechanisms. Joint actions among the local community (households, energy cooperatives, prosumers, virtual prosumers) supported by law, financial incentives could significantly accelerate the energy transformation in Poland. Patterns of energy transformation from other countries (f.e., Germany), which Poland could also apply, will be of particular importance. They concern solutions based on V2-X technology, smart grid solutions, virtual prosumption, local energy communities. In addition, the use of foreign know-how could lower the costs and positively affect the transition to a low-emission economy in Poland. The findings obtained in the course of this study have good application value. They may be employed for verifying the effectiveness and efficiency of public activities in the sphere of pro-environmental investment co-financing and improvement of pro-environmental awareness. In effect, policymakers would be better equipped to properly stimulate the pace of energy transformations, supported by scientific evidence of the level of subsidies deemed acceptable by the homo energeticus segment as well as the level of pro-environmental education required by this segment of consumers.