Although the theoretical proposal is based on the ECM-IT model, there are two modifications necessary for its use in the field of energy. Firstly, the definitions and relationships of the constructs of the ECM-IT model must be adapted to the context of energy technologies. For example, a relevant variable in ECM-IT is perceived usefulness, which in the context of information technology is defined as the degree to which the individual assesses that the use of the technology improves his or her performance (efficiency and/or effectiveness of the individual) [
42]. However, this definition is not appropriate in the energy context, given that a user of gas is not seeking to improve performance in the home. Secondly, it is possible that factors other than those contemplated in ECM-IT may be relevant in the context of energy technologies. A number of authors suggest that, for example, safety or price may influence individuals in deciding to use energy technology.
Figure 2 presents as solid lines the hypotheses derived from ECM and as dotted lines the hypotheses that the energy literature suggests.
2.2.1. ECM-IT in the Context of Energy Technologies
Satisfaction is a net affective response (positive, negative or indifferent) that results from the benefits that a person hopes to receive from interaction with the technology [
43]. Satisfaction is derived from prior technology usage experiences, and can therefore be viewed as an experiential response to technology usage [
16].
Conceptually, the expectation-confirmation literature suggests that consumers/users who have positive feelings relating to the purchase/use experience will be more willing to repurchase a product or continue to use a technology; the opposite will lead to cessation in use [
15]. Empirically, a number of studies in the ICT field support this link (see
Table 1). In the energy literature, the study by Nyrud, Roos [
44] on loyalty in the use of residential biomass heating finds support for this relationship. This is the basis for the following hypothesis:
Hypothesis H1. Satisfaction has a positive impact on continuance intention.
For ECM-IT, usefulness is defined as the degree to which the individual assesses that the technology has improved his performance. An increase in performance implies greater efficiency or effectiveness of the individual [
42].
This definition, conceived in the organizational context, needs to be adapted to the context of energy technology in households. Usefulness was originally seen as an extrinsic motivator through which an individual perceives that following a given behavior (e.g., adopting or using a technology) will be advantageous to them (e.g., they will be more efficient) [
45]. In the context of energy, the literature suggests that usefulness can be seen as the degree to which the individual assesses that the use of an energy technology can improve aspects of his or her daily life, such as saving time, quality of life, ease of carrying out tasks, and so on [
22,
46,
47].
Following the line of ECM-IT, individuals form intentions of certain behaviors (e.g., continuance of use) that they consider will lead them to obtain some benefit (e.g., saving time), beyond positive or negative feelings (e.g., satisfaction) that the behavior may give rise to. This occurs due to the fact that individuals tend to seek rewards or benefits independently of the moment or stage when the behavior is carried out (e.g., adoption or continuance of use) [
15]. Empirically, a number of studies in the ICT field support this relationship (see
Table 1). In the energy literature, the studies by Kardooni, Yusoff [
22], Chen, Xu [
48] and Alam, Hashim [
5] on adoption of renewable energy find indirect support for this link. This leads to the following hypothesis:
Hypothesis H2. Perceived usefulness has a positive impact on continuance intention.
Ease of use of the technology is to be understood as the degree to which the technology is perceived as relatively simple to understand and use [
5,
28]. Theoretically, a technology that is perceived to be user-friendly and family-friendly will facilitate technology usage more than a technology with low ease of use [
5,
28]. Several empirical studies have found support for this link in the context of ICT (see
Table 1). In addition, Park, Kim [
23] in relation to smart grid, Alam, Hashim [
5] and Kardooni, Yusoff [
22] in adoption of renewable energy found indirect support for this relationship. This is the basis for the following hypothesis:
Hypothesis H3. Ease of use has a positive effect on the continuance intention.
As mentioned above, satisfaction is the net feeling that results from benefits that a person expects to receive. Each user has a set of expected benefits for the technology. The user is more or less satisfied if the technology meets or fails to meet each of these expectations. At a minimum, technology is expected to be useful. Beyond that, the more useful the tool, the more likely the user is to be satisfied with it [
43]. Empirically, a set of studies in the ICT field found support for this relationship (see
Table 1). In energy literature, the study by Nyrud, Roos [
44] about residential biomass heating found indirect support for a similar relationship between perceived heating benefits and satisfaction from use. This is the basis for the following hypothesis:
Hypothesis H4. Perceived usefulness has a positive effect on satisfaction.
Previous empirical evidence has shown that perceived ease of use is one of the major cognitive beliefs in determining users’ affect (attitude) towards technology adoption. Given that user satisfaction is a type of affect, perceived ease of use is expected to have a positive influence on a user’s level of satisfaction [
28]. Studies with different ICT contexts support this link (see
Table 1). In the energy field, the study by Toft, Schuitema [
24] about adoption of smart grid technology found indirect support for this relationship. On these grounds, we may establish:
Hypothesis H5. Ease of use has a positive effect on satisfaction.
Conceptually, and following the line of reasoning of Davis, Bagozzi [
13], a technology that is easy to use can increase the perception of usefulness, given that the time and effort saved due to improved ease of use may be redeployed, enabling a person to accomplish more activities for the same effort or to carry out other activities. The empirical evidence supports this relationship in the ICT context (see
Table 1). In addition, Park, Kim [
23], in the context of adoption of smart grid found indirect support of this relationship. For that reason, we may establish:
Hypothesis H6. Ease of use has a positive effect on perceived usefulness.
Confirmation is to be understood as the degree to which the performance of the technology exceeds previous expectations on usefulness or ease of use. The individual evaluates the perceived performance of the technology based on his/her previous expectations and settles the extent to which his/her expectations are confirmed. If the technology performs better than expected, a positive confirmation is expected to occur. Conversely, if the user’s appraisal of the technology falls below the expectation, a negative confirmation occurs [
20].
Following ECM-IT, satisfaction arises when people compare their previous expectations with technology performance during actual usage. Confirmation is related to satisfaction because positive confirmation implies realization of the expected benefits of technology use, while disconfirmation denotes failure to achieve such benefits [
15,
16]. This relationship has been widely supported in the technology context (see
Table 1). For example, Zhou [
40] found that confirmation of mobile service expectations has a positive impact on satisfaction. Likewise, Hung, Chang [
39] found that satisfaction with and web-based learning systems is influenced by the confirmation of expectations. Therefore:
Hypothesis H7. Confirmation has a positive effect on satisfaction.
An individual’s expectations (e.g., about usefulness or ease of use) may be modified over time as the user learns about the technology from his/her first-hand experience. Although low initial expectation is easily confirmed, such expectations may be adjusted higher as a result of the confirmation experience, when users realize that their initial expectations were unrealistically low. Conversely, if their initial expectation is negatively confirmed, they may tone down their future expectations [
15,
16]. Hence, the perceived usefulness or perceived ease of use of a technology are influenced by the confirmation of expectations. Empirically, these relationships have been studied in the technology context (see
Table 1). For example, Hong, Thong [
18] found that confirmation impacts significantly the perceived usefulness of mobile internet. Furthermore, Chong [
41] found that confirmation of expectations about m-commerce influences its perceived ease of use. Consequently, we postulate that:
Hypothesis H8. Confirmation has a positive effect on perceived usefulness.
Hypothesis H9. Confirmation has a positive effect on ease of use.
2.2.2. Extension of the ECM-IT Model in the Context of Energy Technologies
As will be argued later, ECM-IT needs to be extended to reflect the specific context of energy technologies by incorporating three constructs: perceived price, environmental consciousness and perceived safety.
Both the literature on ICTs e.g., [
49,
50] and on energy e.g., [
5,
51,
52] suggest the importance of perception of price on understanding intention of use.
The price level used in most research is not an objective term; rather, it is subjective in that it refers to the perceived level of value paid for a service.
The relationship between price and behavioral intention is supported from several perspectives. For example, the psychological perspective finds that the presence of restrictions (e.g., price) may potentially inhibit behavioral intention [
53,
54]. Similarly, from the marketing perspective, price is an important factor in consumer decisions and thus in intent of consumption [
55,
56]. From the technological perspective, Liao and Cheung [
49] found that price has a significant impact on developing the initial desire in internet purchases. Similarly, Venkatesh and Brown [
57] found that price is relevant in adopting a PC for the home. We therefore propose the following:
Hypothesis H10. The perception of price level has a negative impact on continuance intention of natural gas.
Over the last three decades, consumers have had a growing concern about caring for the environment [
58]. In the energy literature, a number of authors e.g., [
59,
60,
61,
62,
63] suggests its relevance in the context of energy technologies.
Psychology mentions that this environmental concern occurs in the context of the individual’s environmental consciousness. This factor is defined as the tendency to become involved in pro-environmental behaviors that are based on beliefs, values and attitudes [
64,
65,
66]. Thus, an individual with a high level of environmental consciousness will be intrinsically motivated to behave in ways that benefit the environment [
67]. From the perspective of marketing, the level of environmental consciousness appears to condition the way individuals consume or purchase certain products and services. If they have a high level of environmental consciousness, their consumption will be such that they do not damage the environment. If, on the other hand, they have a low level of environmental consciousness, consumers will be less influenced by environmental issues [
67].
In the context of energy, Peters, van der Werff [
52] have found empirical correlation between environmental motivation and sustainable use. In addition, “green marketing” holds that certain levels of environmental consciousness influence the adoption of behaviors relating to consumption of environmentally friendly products (“green buying actions”) p.e., [
64,
68].
In the context of natural gas, which is perceived to be a cleaner technology than more traditional supply (e.g., liquefied petroleum gas—LPG—wood or coal), it may be expected that higher levels of environmental consciousness would lead to an intention to continue using this technology. Based on the above, we propose the following hypothesis:
Hypothesis H11. Environmental consciousness has a positive impact on continuance intention.
Access to modern energy systems (e.g., natural gas) influences human wellbeing through reduction in health and safety risks associated with the use of traditional energy (e.g., LPG. coal or wood) [
69,
70,
71,
72].
A related concept, perceived security, has been widely studied in the marketing literature in subjects relating to the use of technologies for online transactions p.e., [
73,
74,
75]. In this context, security is defined as the degree to which the individual believes that the technological platform to be used is secure for carrying out an activity or transaction, and for protecting the consumer’s sensitive information [
73,
75]. For the purposes of our research, the perception of safety will be defined as the degree to which the individual considers that gas systems are safe in relation to their use.
The marketing and ICT literature has linked perception of security with intention of use or adopting a service e.g., [
74,
75]. Conceptually, when an individual concludes that a service or technology platform is secure, in protecting personal information, preventing risks of fraud or theft, or any other negative consequence in general, there will be a greater likelihood that they will use the service or technology.
Although we have not found evidence to support the link between these variables in the energy systems literature, broad empirical support has been found from the technological context p.e., [
76,
77,
78]. Salisbury, Pearson [
75] find that the perception of security is an important variable in internet purchases. Kim, Tao [
79], for their part, find that the intention of use of electronic payment media benefits more from the beliefs held about the security of the system. We therefore propose the following hypothesis:
Hypothesis H12. Perceived safety positively affects continuance intention.