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Article

Influence of the Parameters of an Agricultural Biogas Plant on the Amount of Power Generated

by
Maciej Kuboń
1,2,
Zbigniew Skibko
3,*,
Andrzej Borusiewicz
4,
Wacław Romaniuk
5,
Jakub St. Gajda
1,
Olivia Kłosowska
6 and
Zbigniew Wasąg
7
1
Department of Production Engineering, Logistics and Applied Computer Science, Faculty of Production and Power Engineering, University of Agriculture in Krakow, Balicka 116B, 30-149 Krakow, Poland
2
Faculty of Technical Sciences and Design Arts, National Academy of Applied Sciences in Przemyśl, Książąt Lubomirskich 6, 37-700 Przemyśl, Poland
3
Faculty of Electrical Engineering, Bialystok University of Technology, Wiejska 45, 15-351 Bialystok, Poland
4
Department of Agronomy, Modern Technology and Informatics, International Academy of Applied Sciences in Lomza, 18-402 Lomza, Poland
5
Institute of Technology and Life Sciences—National Research Insitute, Hrabska 3, 05-090 Falenty, Poland
6
Faculty of Environmental Engineering and Land Surveying, University of Agriculture in Krakow, Al. Mickiewicza 24/28, 30-059 Krakow, Poland
7
Department of Administration, Jan Zamoyski College of Humanities and Economics in Zamość, Ul. Koszary 8, 22-400 Zamość, Poland
*
Author to whom correspondence should be addressed.
Appl. Sci. 2024, 14(10), 4200; https://doi.org/10.3390/app14104200
Submission received: 24 April 2024 / Revised: 11 May 2024 / Accepted: 13 May 2024 / Published: 15 May 2024
(This article belongs to the Special Issue Application of Biomass Energy Technology)
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Abstract

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The research presented by the authors in this article points to the need for changes in the construction of agricultural biogas plants to optimise electricity production.

Abstract

Energy from biogas is widely available, inexpensive, and often contributes to waste management, making it one of the most promising renewable energy sources. The main factors influencing this process’ efficiency include the substrates’ chemical composition, temperature, and digester load. This paper presents the possibilities offered by a biogas plant built at a farm specialising in dairy cows. The dependence of the power generated in the micro biogas plant on its technical parameters was analysed in detail. Studies carried out by the authors in an agricultural microgas plant (with an electrical output of 40 kW) have shown that they are designed to maintain continuous energy production, despite changing process parameters such as digester mass level, biogas height, temperature or slurry flow into the digester. However, from the point of view of the amount of electricity generated, changes would have to be made to the design of the biogas plant. Firstly, a more powerful generator would have to be installed to cover the electricity requirements of the equipment installed in the biogas plant so that power close to the rated capacity of the biogas plant is still sent to the grid. Secondly, replacing the two existing agitators of the digestion mass (9 kW each) with more agitators of lower power (e.g., four agitators of 4.5 kW each) would be necessary. These should be programmed so that one of the agitators operates at any given time (the operating time of a given agitator should depend on the composition of the digestate).

1. Introduction

Electricity is an essential and precious commodity [1]. As fossil energy sources deplete, searching for alternative and renewable energy sources has become urgent [2]. Energy from biogas is widely available and inexpensive [3], often contributes to waste management [4], and does not introduce additional disturbances to the grid [5,6], making it one of the most promising renewable energy sources. The anaerobic digestion in biogas plants produces biogas using methanogenic microorganisms, organic matter, carbon dioxide, and hydrogen. It can produce renewable energy while reducing greenhouse gas emissions [7,8], organic pollutants, pathogens, and slurry odour [9,10]. In addition, biogas production can help mitigate the adverse effects of using fossil fuels [11], the combustion of which has resulted in a significant increase in CO2 concentrations in the atmosphere [12], significantly impacting climate change. Biogas can be an alternative energy source, generating electricity, heat, and cooling or replacing natural gas derived from fossil fuels [13].
The anaerobic digestion process is one of the most promising methods for the disposal of organic waste and a source of biofuel [14,15]. The main factors influencing this process’ efficiency include the substrates’ chemical composition, pH, temperature, digester load, and organic matter content [16,17]. Temperature affects both the physico-chemical properties of oxygen-free substrates and microorganisms’ metabolism and growth rate [18]. It also significantly impacts the stability and efficiency of the fermentation process. Lower temperatures reduce microbial growth, substrate utilisation rate, and biogas production [19]. Exceeding the temperature adopted in the fermentation process reduces the biogas yield due to volatile gases, and the effect of ammonia-inhibiting methane fermentation increases [20,21]. Therefore, the anaerobic digestion process is commonly carried out at mesophilic (35 °C) or thermophilic (55 °C) temperatures [22,23]. Choosing between mesophilic and thermophilic temperatures should be determined by the desired effect and the microorganisms used to treat the waste [24].
Despite the growing interest in biogas projects, many decision-making models tend to prioritise technical and economic factors, pushing social and environmental considerations to the background [25]. A worldwide problem is increased animal waste [26,27], which causes significant environmental problems if not properly managed [28,29,30]. With the increasing demand for food [31,32], one solution is to increase the unit efficiency of animal production (without increasing the livestock population). Many researchers indicate that to reduce greenhouse gas emissions significantly, one can either reduce animal production (and thus, with ever-increasing demand, reduce the supply of food) [33,34] or, with the shortest possible storage period [35], process animal manure in agricultural biogas plants [36,37,38]. In addition, improper storage of manure increases emissions of CH4, N2O, CO2, and NH3 into the atmosphere and contributes to a significant loss of the nutrients present in this manure [39,40]. Such action brings ecological losses (excessive emissions, leaching) and financial losses (higher manure application rates per hectare are necessary) [41,42]. Biogas plants are increasingly built next to sewage treatment plants [43].
While electricity generation may prove economically viable in large biogas plants, success is no longer evident in microgas plants. In such installations, the price of electricity and the need for capital to purchase and maintain an electrical generator significantly impact their profitability [44,45]. In addition, the technical conditions for connecting such an energy source at the location must exist [46,47]. An essential argument for constructing biogas plants is the reduction of unpleasant odours from the substrates used in the fermentation process [7,29,48]. Although these gains are difficult to quantify and often not included in economic assessments, the costs of odour reduction can be considered the price of continuing operations as residential areas encroach on land previously occupied by rural farms [7]. The costs associated with constructing biogas plants, calculated per cow, decrease with the increase in herd size. However, no correlation has been found between investment costs and the design of the digester or the presence or absence of electric generators [49]. The equipment must undergo regular maintenance and servicing to optimise the plant’s efficiency and longevity [50]. This significantly impacts the operational costs of the biogas facility [30,51].
Investing in biogas plants on dairy farms, in addition to the reduction of greenhouse gas emissions and the reduction of unpleasant odours, results in an increase in the income indicators of the farm in question [52]. The revenue from electricity production in a biogas plant is approximately EUR 20/MWh higher than the average electricity price in the second quarter of 2023 [53]. Selling the heat produced in the biogas plant or using it for a farm’s needs would yield an additional profit of approximately EUR 35 per GJ [54]. It should be noted that the payback period for an agricultural biogas plant is just over six years [52] (financially favourable investments with a payback of 5–8 years are considered [55,56,57]). In the case of microbial biogas plants, where no investment in land is required, a payback period of even less than five years is achieved [52]. In comparison, an investment in a PV plant typically pays for itself within five to six years [58].
Biogas, resulting from the anaerobic digestion of agricultural waste, can be used for a variety of purposes (fuel, electricity, heat, cooling) [59]. Agricultural waste includes crop residues, animal manure [60], and other farm organic waste [61]. These substrates are readily available and easily harvested, making them popular for biogas production. In Europe, around 23 Mt of dry biomass is produced annually as straw residues from cereals, and in India and China, up to 368 Mt and 649 Mt of straw residues per year, respectively [62]. The composition of agricultural waste depends mainly on the type of crop or animal, which can affect both the quantity and quality of the biogas produced. Although manure is the most suitable substrate for reducing greenhouse gas emissions, it has a low energy value (due to its low organic matter content and high ammonium concentration) [63,64]. For example, cattle slurry, biogas, and methane yield 25 Nm3 and 14 Nm3 per tonne of substrate, respectively [65]. Hence, the co-digestion of manure and other feedstocks is often used (to improve biogas yield) [66,67,68]. The digested animal manure (digestate) can be used as full-fledged manure [69,70,71].
Biogas power plants are among the renewable energy sources characterised by the constancy of the generated power over time. This was confirmed by the authors’ earlier studies conducted in biogas plants connected to the medium voltage grid [4]. However, there is a lack of analysis in the literature of research results that would present the dependence of the power generated in microgas plants on the technical parameters of the biogas plant. Therefore, the authors decided to fill this research gap by conducting a comprehensive study at one micro biogas plant installed in Poland, in the Podlaskie Province.

2. Materials and Methods

The research was carried out in an agricultural biogas plant derived from a substrate from dairy cows raised in a barnless system (a technological diagram of the biogas plant under study is shown in Figure 1). The agricultural biogas plant consisted of a digester with a diameter of 15.5 m and a wall height of 3.7 m. The total height of the digester, including the biogas balloon, was 8.7 m. It allowed for a nominal storage of 590 m3 of substrate. Two agitators with a rated power of 9 kW each were installed in the chamber to maintain a homogeneous digestion mass. The agitators installed in the biogas plant were of the medium-speed type, and their speed did not exceed 700 rpm. Both agitators were switched on simultaneously every 30 min, and their operating time was 3 min. In excess foam formation, a mechanical foam beater was automatically activated. The water system installed in the chamber enabled a constant temperature to be maintained during the digestion process. The ratings showed that the biogas plant under study performed fermentation at a target temperature of 42 °C. Another component of the biogas plant was the container in which the combustion engine was connected to the generator, and other technical equipment for pumping and purifying the biogas and controlling the technological processes of the biogas plant were installed. The biogas was pre-treated in a gas filter and then flowed through a carbon filter filled with activated carbon. The biogas produced in the reactor was combusted in two internal combustion engines with a capacity of 20 kW each. The basic specifications of the generators are given in Table 1. The biogas-burning engine was cooled by circulating water in the engine and the cooling block. The final component of the biogas plant was a concrete, open-air digestate tank.
The engine and generator were mounted on a rigid frame with belt drive, all fitted with vibration dampers. The exhaust system and manifold worked together with an exhaust gas heat exchanger.
Slurry from the barn was pumped into the digester, where fermentation occurred under anaerobic conditions. The average length of time of the substrate in the fermenter (hydraulic retention time) was between 2 and 3 weeks—the slurry spent no less than 12 days in the digester. The following formula describes the hydraulic retention time (HRT):
H R T = V R V
where HRT—hydraulic retention time [day], VR—active digester volume [m3], and V—daily digester input volume [m3/day].
The bacteria’s reproducing ability is essential when determining the hydraulic retention time. Methanogenic bacteria, for example, need up to several days to double their population. Therefore, in the absence of feeding the digester with bacterial strains (e.g., by feeding slurry), a retention time of less than 20 days is not recommended.
Daily, part of the digested slurry was pumped from the digestion reactor into the digestate tank. The dose of pumped digestate was controlled automatically and depended on the amount of biogas produced, which in turn depended on the parameters of the slurry fed in. A pressure sensor determined the charge level in the reactor. Once the process of pumping out the digestate was complete, when the pressure dropped below the set value, a new slurry was pumped out of the collection channel to compensate for the substrate’s shortfall.
The volumetric load is a parameter that determines how many kg of dry organic matter should be supplied to the digester about its volume, described by the following relationship [72]:
B = m × c V R
where B—volume load of the digester, VD—daily volume of slurry flow into the digester [m3/day], CD—concentration of organic dry matter in the substrate [kg d.m./m3], and VR—active volume of the digester [m3].
It is one of the critical process parameters determining the amount of biogas produced. Daily biogas production increases until the volume load limit is reached. Once this limit is exceeded, biogas production decreases despite the more significant amount of raw material available, which is related to the phenomenon of chamber overload. Therefore, it is vital to determine the optimum chamber load, which allows for efficient and economical methane production.
A relationship describing the biogas production potential of a digester, taking into account many variables, was developed by Binxin et al. [73] as follows:
B G = 0.5 H R T C 0 − C T x , t × V R × T a T 0
where BG—daily biogas production [kg/day], HRT—hydraulic retention time [day], C0—organic dry matter input (C0 = 0.863. s.m.) [kg/m3], VR—active volume of the digester [m3], T0—assumed fermentation temperature [K], Ta—273.2 [K], and CT(x,t)—total degradation of the substrate in the digester [kg/m3] described by the relation
C T x , t = C 0 · K · e − 1 / k μ m 2 · V R · t × V R × μ m − 2 × v × k × 1 − e − μ m × t k + t × v × μ m × 1 + e − μ m × t k
where v—daily flow of slurry into the digester [m3/day], t—maximum hydraulic retention time for decomposition at a specific point [day], K—kinetic parameter experimentally determined by Hashimoto (K = 1.26), and µm—daily bacterial growth.
Using Equation (4), the total degradation of the substrate can be calculated in addition to biogas production. The model uses an equation that makes it possible to describe the growth rate of microorganisms. It has been validated by numerous experiments with excellent results (the results overlapped a high percentage with those obtained experimentally) [74].
The main medium studied in the agricultural microgas plant was electricity. Therefore, the priority was maintaining its production at the highest possible level. Measurements of the parameters describing electricity at the point of connection of the biogas plant to the electricity grid were performed using the SONEL PQM-701 electricity quality analyser (Sonel, Swidnica, Poland).

3. Results

3.1. Recorded Parameters for the Biogas Plant under Study

The first parameter measured in the agricultural biogas plant studied was the temperature of the digestion mass—Figure 2. According to the technical specifications of the biogas plant, the digestion process should be carried out at 42 °C.
As can be seen from Figure 1, the average temperature of the fermentation mass was 36 °C during the measurements, with a maximum deviation of ±1 °C. It is an average temperature of 6 °C lower than the value reported in the catalogue data. Nevertheless, it is more similar to the values attributed in the literature [22,23] for mesophilic fermentations (35 °C). Consequently, we assert that the fermenter temperature value presented in the technical documentation appears inaccurate and necessitates significant rectification.
The slurry flow (Figure 3) and the height of the digester mass (Figure 4) were also measured to determine the slurry used for biogas production.
The mean recorded slurry flow was 57.5 m3, with a standard deviation of 10 m3. The maximum slurry flow rate during the recording period was 76 m3, with a minimum of 24 m3. Despite this significant variation in the amount of slurry pumped into the digester, the digester mass level averaged 1.65 m throughout the recording period, with a standard deviation of 0.06 m (extreme values were 1.55 and 1.75 m, respectively). This is mainly because the digester mass was topped up with fresh slurry, according to the scheme described in the technical data of the biogas plant.
The anaerobic digestion process in the digester produced biogas, which was collected in the tank dome. The recorded amount of biogas described by the height of the dome is shown in Figure 5.
The level of biogas accumulated in the digester was also not constant and varied from 2.08 to 3.74 m (the average biogas volume at the time of recording was 2.95 m). The recorded changes in the amount of biogas and the digester mass level may be due to using a pressure sensor in the digester. Perhaps a better solution would be to use a height sensor (digester mass level) for this purpose.
The biogas produced was burned in internal combustion engines installed in the biogas container. The amount of active power P and reactive power Q fed into the electricity grid, minus the biogas plant’s own needs, is shown in Figure 6.
From an analysis of the waveforms shown in Figure 6, several relationships can be seen:
  • The agricultural biogas plant studied never reached its rated output (40 kW); the highest recorded active power value was 38.3 kW, 96% of the rated power; this was most likely due to the energy consumption of the individual electrical appliances of the biogas plant (the plant’s own needs) and the power losses occurring in their current paths;
  • The minimum active power value recorded during the tests was only 17.8 kW, resulting from the operation of the mixers (rated at 2 × 9 kW) installed in the digester; the actual power consumed by the substrate mixers was lower, at around 14.2 kW;
  • The reactive power produced in the biogas plant was inductive and took values of 9.8 kvar to 23.6 kvar; during regular system operation, the reactive power took on lower values, while switching on the substrate mixers increased it by an average of 6.6 kvar.

3.2. Statistical Analysis of the Results Obtained

Correlations between these quantities were determined to determine the influence of the basic parameters of the biogas plant on the amount of power generated in the agricultural biogas plant under study (Table 2).
From the analysis of the values presented in Table 2, it can be seen that, in the case of the height of the substrate in the digester, no significant correlation was observed with the other parameters recorded. The other correlations tested, although mathematically significant, are much smaller than 1 (the highest calculated value is 0.26).
Figure 7 shows a scatter plot of the recorded active power values P as a function of the height of the substrate in the digester. From the measurement points presented there, it appears that the amount of power generated in an agricultural biogas plant does not depend on the height of the digestate in the digester. Assuming that the level of the digestion mass in the fermenter changes due to the action of the pumps supplying new substrate and pumping out the digestate, no closer correlation between the substrate level and the power fed into the electricity grid was observed.
A similar relationship emerged between the amount of power generated and the slurry supplied to the digester (Figure 8). In this case, however, it can be seen that, as the amount of slurry pumped into the digester increases, there is a noticeable, slight decrease in the generated power sent to the electricity grid. This is most likely related to the increased power consumption of the pumps pumping the slurry into the chamber (the increased power demand from these pumps causes a decrease in the power injected into the electricity grid).
An analogous relationship can be observed between power and biogas levels (Figure 9). Although, according to the adopted approximation, the amount of power decreases slightly as the amount of biogas increases, this change is negligible and does not exceed 2 kW over the entire recording period.
To check the correlation between the amount of biogas in the biogas plant and the slurry flow into the digester, a correlation of these values was drawn up (Figure 10).
As can be seen from the distribution of values shown in Figure 10, an increase in the amount of slurry pumped into the biogas plant has a positive effect on the amount of biogas produced. This is most likely the result of supplying the digester with large amounts of new ‘fuel’ from which the methane bacteria can produce methane much more quickly. At the same time, it is worth noting that injecting a new substrate (with a temperature lower than the temperature prevailing in the fermenter) does not significantly affect the temperature of the entire fermentation mass (Figure 10). Although the correlation shown in Figure 11 is positive, due to the low value of the correlation coefficient (r = 0.175), it can be concluded that the observed increase in temperature with increasing flow is negligibly slight and is due to a measurement error (the measured temperature was rounded to the nearest whole degree Celsius).
An analogous lack of correlation can be seen when comparing the amount of biogas with the temperature prevailing in the fermenter (Figure 12). In this case, the correlation is positive, as in the flow case, but this cannot be considered a reliable relationship due to the low correlation coefficient value (r = 0.114).
There is a lack of correlation (Figure 13) when the digester height and temperature are compared (the correlation coefficient r is only 0.05). This confirms the earlier statement that the temperature in the digester is kept constant, regardless of the processes currently taking place in the biogas plant. In particular, no correlation was observed between the injection of new substrate into the digester (change in digestion mass level) and the temperature value in the chamber. If such a phenomenon is observed, preheating the slurry pumped into the digester should be introduced. With a constant temperature value of 36 °C ± 2.78%, the methane fermentation reaction can proceed stably.
An interesting relationship between the amount of slurry pumped into the digester and the substrate height can be found. One would expect that the substrate level would increase significantly as new slurry was pumped into the digester. However, as seen from the graph in Figure 14, slurry pumping does not affect the height of the substrate in the digester. This is due to two factors. Firstly, in parallel to the injected slurry, the already digested part of the slurry is pumped into the digestate tank. The second factor influencing the consistency of the digestate height obtained in the study is that the graphs show average values from 15 min of measurements.
As can already be expected, an analogous lack of a relationship was registered between the height of the substrate and the amount of biogas (Figure 15). Even though the level of the digestion mass varied from 1.55 to 1.75 m during the measurements, these changes did not directly affect the biogas level present in the reactor.

4. Discussion

Correctly selecting the essential components in an agricultural biogas plant is a fundamental factor in this type of investment’s economic and functional success. It must also withstand the changing parameters of the anaerobic digestion process. In the biogas plant analysed, the temperature of the digestion mass varied between 34 and 37 °C, which, according to [22,23], qualifies the process as mesophilic. However, this is significantly lower than the 42 °C indicated in the technical documentation. Studies have shown that changing the temperature value during digestion (within the recorded limits) does not directly affect the amount of biogas produced or the amount of power generated in the generator [10]. Properly designed digesters do not allow biogas shortages or excesses to occur. This was the case for the agricultural biogas plant studied. The selected digester volume and the programmed slurry flow allowed biogas to be produced in such quantities (the biogas horizon during the recording period ranged from about 2.1 to 3.7 m) as to ensure that there was sufficient biogas, regardless of the slurry and digestate flow, while maintaining constant electricity generation. The correct setting of the slurry and digestate flows also ensures that the amount of digestate present in the fermenter varies little (its height in the biogas plant analysed varied between 1.55 and 1.75 m).
The chemical composition of the biogas produced in the biogas plant was also checked during the study. The most significant proportion of methane in the biogas studied was 50.8%, at the lower end of the range of methane in biogas reported in the literature [37,48,75]. The carbon dioxide content was as high as 44.3% and was higher than the ranges reported in other publications [48,76]. Oxygen was only 0.7%, and hydrogen sulphide was 28 ppm. The above parameters were measured before the biogas was subjected to the treatment process. These values indicate that the biogas production process in the agricultural biogas plant under investigation should be optimised, e.g., using the solutions described in [37]. The authors will pursue this topic in further studies.

5. Conclusions

As the authors’ research has shown, despite the correct sizing of biogas production equipment and flow control system settings, several improvements can be made in microgas plants. It would be prudent to augment the electric generator’s capacity to fully leverage the connection power derived from the agreement between the biogas plant proprietor and the power company. It would be wise to ensure it can meet the plant’s internal requirements while feeding power into the grid, nearly matching the connection power. In addition, it would be worth considering changing the number and operating system of the digestion mixers. In the biogas plant under consideration, both mixers operate simultaneously, which decreases the power fed into the electrical system by an average of approximately 14.2 kW (almost half of the power generated in the biogas plant). The optimum solution would be to install several lower-power mixers that could operate in a rotating system (only one of the mixers is always on, with no breaks in substrate mixing). This would result in an even load on the system, increasing the generator power to a value that would cover the resulting demand and enable power to be fed into the grid close to the connection power. In the case of the biogas plant analysed, installing four agitators of 4.5 kW each and putting them into alternating operation would allow the generator power to be increased to 24.5 kW without reducing the power fed into the grid. In addition, tests should be carried out on the effect of the speed and running time of the individual agitators on the quantity and quality of the biogas produced. Such an action could affect the payback time, which could be significantly shorter than the assumed six years [50]. Limiting the variation in the value of the active power generated in the system reduces the dispersion of the value of the reactive power taken from the grid. This allows for a more straightforward construction and the proper operation of compensation systems, reducing penalties for excessive reactive power consumption to practically zero.
In the future, the authors plan to carry out further tests on the biogas plant to optimise the biogas production process, which is to include, among other things, an analysis of the impact of changes in substrate volume and temperature on the quantity and quality of the biogas produced. It is also planned to introduce the changes indicated in this article and to determine their actual impact on the operation of the studied agricultural biogas plant.

Author Contributions

Conceptualisation, M.K. and Z.S.; methodology, Z.S.; software, A.B.; validation, M.K., Z.S. and Z.W.; formal analysis, Z.S. and O.K.; investigation, J.S.G. and Z.W.; resources Z.S.; data curation, W.R., A.B. and Z.S; writing—original draft preparation, Z.S., O.K. and Z.W.; writing—review and editing, A.B. and W.R.; visualisation, J.S.G. and O.K.; supervision, W.R.; project administration, Z.S. and A.B.; funding acquisition, M.K. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data are contained within the article.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Hołdyński, G.; Skibko, Z. Analysis of Currents and Voltages Deformations in Rural Medium Voltage Electric Power Networks. Przegląd Elektrotechniczny 2011, 7, 130–135. Available online: https://www.sigma-not.pl/publikacja-60808-analiza-odkszta%C5%82ce%C5%84-prad%C3%B3w-i-napi%C4%99%C4%87-w-tereno-wych-sieciach-elektroenergetycznych-%C5%9Bredniego-napi%C4%99cia-przeglad-elektrotechniczny-2011-7.htmlprad%C3%B3w-i-napi%C4%99%C4%87-w-terenowych-sieciach-elektroenergetycznych-%C5%9Bredniego-napi%C4%99cia-przeglad-elektrotechniczny-2011-7.html (accessed on 1 April 2024). (In Polish).
  2. Igliński, B.; Kiełkowska, U.; Pietrzak, M.B.; Skrzatek, M.; Kumar, G.; Piechota, G. The regional energy transformation in the context of renewable energy sources potential. Renew. Energy 2023, 218, 119246. [Google Scholar] [CrossRef]
  3. Pilarski, K.; Pilarska, A.A.; Boniecki, P.; Niedbała, G.; Durczak, K.; Witaszek, K.; Mioduszewska, N.; Kowalik, I. The efficiency of industrial and laboratory anaerobic digesters of organic substrates: Using the Biochemical Methane Potential Correction Coefficient. Energies 2020, 13, 1280. [Google Scholar] [CrossRef]
  4. Tymińska, M.; Skibko, Z.; Borusiewicz, A. The Effect of Agricultural Biogas Plants on the Quality of Farm Energy Supply. Energies 2023, 16, 4600. [Google Scholar] [CrossRef]
  5. Kuboń, M.; Skibko, Z.; Tabor, S.; Malaga-Toboła, U.; Borusiewicz, A.; Romaniuk, W.; Zarajczyk, J.; Neuberger, P. Analysis of Voltage Distortions in the Power Grid Arising from Agricultural Biogas Plant Operation. Energies 2023, 16, 6189. [Google Scholar] [CrossRef]
  6. Hołdyński, G.; Skibko, Z.; Borusiewicz, A. Analysis of the Influence of Load on the Value of Zero-Voltage Asymmetry in Medium-Voltage Networks Operating with Renewable Energy Sources. Energies 2023, 16, 580. [Google Scholar] [CrossRef]
  7. Garrison, M.V.; Richard, T.L. Methane and Manure: Feasibility Analysis of Price and Policy Alternatives. Trans. ASAE 2005, 48, 1287–1294. [Google Scholar] [CrossRef]
  8. Lansing, S.; Martin, J.F.; Botero, R.B.; da Silva, T.N.; da Silva, E.D. Wastewater transformations and fertilizer value when co-digesting differing ratios of swine manure and used cooking grease in low-cost digesters. Biomass Bioenergy 2010, 34, 1711–1720. [Google Scholar] [CrossRef]
  9. Rao, P.V.; Baral, S.S.; Dey, R.; Mutnuri, S. Biogas generation potential by anaerobic digestion for sustainable energy development in India. Renew. Sustain. Energy Rev. 2010, 14, 2086–2094. [Google Scholar] [CrossRef]
  10. Chen, Y.; Yang, G.; Sweeney, S.; Feng, Y. Household biogas use in rural China: A study of opportunities and constraints. Renew. Sustain. Energy Rev. 2010, 14, 545–549. [Google Scholar] [CrossRef]
  11. Saracevic, E.; Frühauf, S.; Miltner, A.; Karnpakdee, K.; Munk, B.; Lebuhn, M.; Wlcek, B.; Leber, J.; Lizasoain, J.; Friedl, A.; et al. Utilisation of food and agricultural residues for flexible biogas production: Process stability and effects on needed biogas storage capacities. Energies 2019, 12, 2678. [Google Scholar] [CrossRef]
  12. Friedlingstein, P.; O’Sullivan, M.; Jones, M.W.; Andrew, R.M.; Hauck, J.; Olsen, A.; Peters, G.P.; Peters, W.; Pongratz, J.; Sitch, S.; et al. Global carbon budget. Earth Syst. Sci. Data 2020, 12, 3269–3340. [Google Scholar] [CrossRef]
  13. Korberg, A.D.; Skov, I.R.; Mathiesen, B.V. The role of biogas and biogas-derived fuels in a 100% renewable energy system. Energy 2020, 199, 117426. [Google Scholar] [CrossRef]
  14. Ardolino, F.; Parrillo, F.; Arena, U. Biowaste-to-biomethane or biowaste-to-energy? An LCA study on anaerobic digestion of organic waste. J. Clean. Prod. 2018, 174, 462–476. [Google Scholar] [CrossRef]
  15. Hagos, K.; Zong, J.; Li, D.; Liu, C.; Lu, X. Anaerobic co-digestion process for biogas production: Progress, challenges and perspectives. Renew. Sustain. Energy Rev. 2017, 76, 1485–1496. [Google Scholar] [CrossRef]
  16. Pilarska, A.A.; Wolna-Maruwka, A.; Pilarski, K. Kraft Lignin Grafted with Polyvinylpyrrolidone as a Novel Microbial Carrier in Biogas Production. Energies 2018, 11, 3246. [Google Scholar] [CrossRef]
  17. Piechocki, J.; Solowiej, P.; Neugebauer, M. The use of biomass for electric power production in polish power plants. Hung. Agric. Eng. 2015, 28, 19–22. [Google Scholar] [CrossRef]
  18. Amani, T.; Nosrati, M.; Sreekrishnan, T.R. Anaerobic digestion from the viewpoint of microbiological, chemical, and operational aspects—A review. Environ. Rev. 2010, 18, 255–278. [Google Scholar] [CrossRef]
  19. Khalid, A.; Arshad, M.; Anjum, M.; Mahmood, T.; Dawson, L. The anaerobic digestion of solid organic waste. Waste Manag. 2011, 31, 1737–1744. [Google Scholar] [CrossRef]
  20. Nie, H.; Jacobi, H.F.; Strach, K.; Xu, C.; Zhou, H.; Liebetrau, J. Mono-fermentation of chicken manure: Ammonia inhibition and recirculation of the digestate. Bioresour. Technol. 2015, 178, 238–246. [Google Scholar] [CrossRef]
  21. Bousek, J.; Scroccaro, D.; Sima, J.; Weissenbacher, N.; Fuchs, W. Influence of the gas composition on the efficiency of ammonia stripping of biogas digestate. Bioresour. Technol. 2016, 203, 259–266. [Google Scholar] [CrossRef]
  22. Pilarska, A.A.; Pilarski, K.; Waliszewska, B.; Zborowska, M.; Witaszek, K.; Waliszewska, H.; Kolasinski, M.; Szwarc-Rzepka, K. Evaluation of bio-methane yields for high-energy organic waste and sewage sludge: Apilot-scale study for a wastewater treatment plant. Environ. Eng. Manag. J. 2019, 18, 2023–2034. [Google Scholar] [CrossRef]
  23. Moset, V.; Poulsen, M.; Wahid, R.; Højberg, O.; Møller, H.B. Mesophilic versus thermophilic anaerobic digestion of cattle manure: Methane productivity and microbial ecology. Microb. Biotechnol. 2015, 8, 787–800. [Google Scholar] [CrossRef]
  24. Kreuger, E.; Nges, I.; Björnsson, L. Ensiling of crops for biogas production: Effects on methane yield and total solids determination. Biotechnol. Biofuels 2011, 4, 44. [Google Scholar] [CrossRef]
  25. Yamaji, D.M.; Amâncio-Vieira, S.F.; Fidelis, R.; Contani, E.A.D.R. Proposal of Multicriteria Decision-Making Models for Biogas Production. Energies 2024, 17, 806. [Google Scholar] [CrossRef]
  26. Mazurkiewicz, J. Analysis of the Energy and Material Use of Manure as a Fertilizer or Substrate for Biogas Production during the Energy Crisis. Energies 2022, 15, 8867. [Google Scholar] [CrossRef]
  27. Hamzehkolaei, F.T.; Amjady, N. A Techno-Economic Assessment for Replacement of Conventional Fossil Fuel Based Technologies in Animal Farms with Biogas Fueled CHP Units. Renew. Renew. Energy 2018, 118, 602–614. [Google Scholar] [CrossRef]
  28. Aguirre-Villegas, H.A.; Larson, R.A. Evaluating Greenhouse Gas Emissions from Dairy Manure Management Practices Using Survey Data and Lifecycle Tools. J. Clean. Prod. 2017, 143, 169–179. [Google Scholar] [CrossRef]
  29. Czekała, W.; Nowak, M.; Bojarski, W. Anaerobic Digestion and Composting as Methods of Bio-Waste Management. Agric. Eng. 2023, 27, 173–186. [Google Scholar] [CrossRef]
  30. Larina, Y.; Galchynska, J.; Kucheruk, P.; Zghurska, O.; Ortina, G.; Al-Nadzhar, F.; Marusei, T.; Kuboń, M.; Dzieniszewski, U. Estimation of the Domestic Agricultural Sector Potential for the Growth of Energy Cultures for Bioenergy Fuel Production. Agric. Eng. 2021, 25, 73–82. [Google Scholar] [CrossRef]
  31. Piwowar, A. Farming Practices for Reducing Ammonia Emissions in Polish Agriculture. Atmosphere 2020, 11, 1353. [Google Scholar] [CrossRef]
  32. Roubik, H.; Mazancova, J. Suitability of Small-Scale Biogas Systems Based on Livestock Manure for the Rural Areas of Sumatra. Environ. Dev. 2020, 33, 100505. [Google Scholar] [CrossRef]
  33. Eisen, M.B.; Brown, P.O. Rapid Global Phaseout of Animal Agriculture Has the Potential to Stabilise Greenhouse Gas Levels for 30 Years and Offset 68 Percent of CO2 Emissions This Century. PLoS Clim. 2022, 1, e0000010. [Google Scholar] [CrossRef]
  34. Hayek, M.N.; Harwatt, H.; Ripple, W.J.; Mueller, N.D. The Carbon Opportunity Cost of Animal-Sourced Food Production on Land. Nat. Sustain. 2021, 4, 21–24. [Google Scholar] [CrossRef]
  35. Díaz-Vázquez, D.; Alvarado-Cummings, S.C.; Meza-Rodríguez, D.; Senés-Guerrero, C.; de Anda, J.; Gradilla-Hernández, M.S. Evaluation of Biogas Potential from Livestock Manures and Multicriteria Site Selection for Centralized Anaerobic Digester Systems: The Case of Jalisco, México. Sustainability 2020, 12, 3527. [Google Scholar] [CrossRef]
  36. Achinas, S.; Euverink, G.J.W. Rambling Facets of Manure-Based Biogas Production in Europe: A Briefing. Renew. Sustain. Energy Rev. 2019, 119, 109566. [Google Scholar] [CrossRef]
  37. Kegl, T.; Kegl, B.; Kegl, M. Improvement of Biogas Production Utilising a Complex Anaerobic Digestion Model and Gradient-Based Optimization. Energies 2024, 17, 1279. [Google Scholar] [CrossRef]
  38. Skibko, Z.; Romaniuk, W.; Borusiewicz, A.; Porwisiak, H.; Lisowski, J. Use of pellets from agricultural biogas plants in fertilisation of oxytrees in Podlasie, Poland. J. Water Land Dev. 2021, 51, 124–128. [Google Scholar] [CrossRef]
  39. Zhang, X.; Lassaletta, L. Manure management benefits climate with limits. Nat. Food 2022, 3, 312–313. [Google Scholar] [CrossRef]
  40. Köninger, J.; Lugato, E.; Panagos, P.; Kochupillai, M.; Orgiazzi, A.; Briones, M.J. Manure Management and Soil Biodiversity: Towards More Sustainable Food Systems in the EU. Agric. Syst. 2021, 194, 103251. [Google Scholar] [CrossRef]
  41. Shan, N.; Li, H.; Li, J.-Z.; Ng, E.L.; Ma, Y.; Wang, L.-G.; Chen, Q. A Major Pathway for Carbon and Nitrogen Losses-Gas Emissions during Storage of Solid Pig Manure in China. J. Integr. Agric. 2019, 18, 190–200. [Google Scholar] [CrossRef]
  42. Hristov, A.N.; Hanigan, M.; Cole, A.; Todd, R.; McAllister, T.A.; Ndegwa, P.M.; Rotz, A. Ammonia emissions from dairy farms and beef feedlots. Can. J. Anim. Sci. 2011, 91, 1–35. [Google Scholar] [CrossRef]
  43. González, J.F.; Álvez-Medina, C.M.; Nogales-Delgado, S. Biogas Steam Reforming in Wastewater Treatment Plants: Opportunities and Challenges. Energies 2023, 16, 6343. [Google Scholar] [CrossRef]
  44. Giesy, R.; Wilkie, A.C.; De Vries, A.; Nordstedt, R.A. Economic Feasibility of Anaerobic Digestion To Produce Electricity on Florida Dairy Farms. EDIS 2006, 2006, 1–8. [Google Scholar] [CrossRef]
  45. Gloy, B.A.; Dressler, J.B. Financial barriers to the adoption of anaerobic digestion on US livestock operations. Agric. Financ. Rev. 2010, 70, 157–168. [Google Scholar] [CrossRef]
  46. Sołjan, Z.; Hołdyński, G.; Zajkowski, M. Balancing reactive compensation at three-phase four-wire systems with a sinusoidal and asymmetrical voltage source. Bull. Pol. Acad. Sci. Tech. Sci. 2020, 68, 71–79. [Google Scholar] [CrossRef]
  47. Soljan, Z.; Holdynski, G.; Zajkowski, M. Decomposition of the load’s current supplied from a sinusoidal and asymmetrical voltage source in accordance with the Currents’ Physical Components (CPC) Theory. In Proceedings of the 2019 20th International Scientific Conference on Electric Power Engineering (EPE), Kouty nad Desnou, Czech Republic, 15–17 May 2019; Rusek, S., Goňo, R., Eds.; pp. 389–394. [Google Scholar]
  48. Lansing, S.; Botero, R.B.; Martin, J.F. Waste treatment and biogas quality in small-scale agricultural digesters. Bioresour. Technol. 2008, 99, 5881–5890. [Google Scholar] [CrossRef] [PubMed]
  49. Bórawski, P.; Bełdycka-Bórawska, A.; Kapsdorferová, Z.; Rokicki, T.; Parzonko, A.; Holden, L. Perspectives of Electricity Production from Biogas in the European Union. Energies 2024, 17, 1169. [Google Scholar] [CrossRef]
  50. Ankathi, S.K.; Chaudhari, U.S.; Handler, R.M.; Shonnard, D.R. Sustainability of Biogas Production from Anaerobic Digestion of Food Waste and Animal Manure. Appl. Microbiol. 2024, 4, 418–438. [Google Scholar] [CrossRef]
  51. Dach, J.; Boniecki, P.; Przybył, J.; Janczak, D.; Lewicki, A.; Czekała, W.; Witaszek, K.; Carmona, P.C.R.; Cieślik, M. Energetic efficiency analysis of the agricultural biogas plant in 250 kWe experimental installation. Energy 2014, 69, 34–38. [Google Scholar] [CrossRef]
  52. Mazurkiewicz, J. The Impact of Manure Use for Energy Purposes on the Economic Balance of a Dairy Farm. Energies 2023, 16, 6735. [Google Scholar] [CrossRef]
  53. United States Environmental Protection Agency. Practices to Reduce Methane Emissions from Livestock Manure Management. Available online: https://www.epa.gov/agstar/practices-reduce-methane-emissions-livestock-manure-management (accessed on 23 October 2023).
  54. Energy Market, U.R. Energy Market: Average Electricity Price from Generator Settlements within Groups in Q2 2023. Available online: https://www.ure.gov.pl/pl/urzad/informacje-ogolne/aktualnosci/11215,Rynek-energii-srednia-cena-energii-elektrycznej-z-rozliczen-wytworcow-w-ramach-g.html (accessed on 23 October 2023).
  55. Bôas, T.F.V.; Barros, R.M.; Pinto, J.A.; dos Santos, I.F.S.; Lora, E.E.S.; Andrade, R.V.; Filho, G.L.T.; Almeida, K.A.; Machado, G.d.O. Energy Potential from the Generation of Biogas from Anaerobic Digestion of Olive Oil Extraction Wastes in Brazil. Clean. Waste Syst. 2023, 4, 100083. [Google Scholar] [CrossRef]
  56. Tan, V.W.G.; Chan, Y.J.; Arumugasamy, S.K.; Lim, J.W. Optimising Biogas Production from Palm Oil Mill Effluent Utilising Integrated Machine Learning and Response Surface Methodology Framework. J. Clean. Prod. 2023, 414, 137575. [Google Scholar] [CrossRef]
  57. Furtado, L.A.; Ribeiro, S.G.; Pradelle, F.; Parise, J.A.R. Modeling and Techno-Economic Analysis of a Hybrid Sugar-cane Plant Fed by Vinasse Biogas and Bagasse Surplus for Electricity Generation. J. Clean. Prod. 2023, 413, 137511. [Google Scholar] [CrossRef]
  58. Wind, Solar Payback Times under a Year in Some Parts of World, Says Rystad. Available online: https://www.pv-magazine.com/2022/10/14/wind-solar-payback-times-under-a-year-in-some-parts-of-world-says-rystad/ (accessed on 23 October 2023).
  59. Ciuła, J.; Kowalski, S.; Generowicz, A.; Barbusiński, K.; Matuszak, Z.; Gaska, K. Analysis of Energy Generation Efficiency and Reliability of a Cogeneration Unit Powered by Biogas. Energies 2023, 16, 2180. [Google Scholar] [CrossRef]
  60. Battini, F.; Agostini, A.; Boulamanti, A.; Giuntoli, J.; Amaducci, S. Mitigating the environmental impacts of milk production via anaerobic digestion of manure: Case study of a dairy farm in the Po Valley. Sci. Total Environ. 2014, 481, 196–208. [Google Scholar] [CrossRef]
  61. Launay, C.; Houot, S.; Frédéric, S.; Girault, R.; Levavasseur, F.; Marsac, S.; Constantin, J. Incorporating energy cover crops for biogas production into agricultural systems: Benefits and environmental impacts. A review. Agron. Sustain. Dev. 2022, 42, 57. [Google Scholar] [CrossRef]
  62. Ufitikirezi, J.d.D.M.; Filip, M.; Ghorbani, M.; Zoubek, T.; Olšan, P.; Bumbálek, R.; Strob, M.; Bartoš, P.; Umurungi, S.N.; Murindangabo, Y.T.; et al. Agricultural Waste Valorization: Exploring Environmentally Friendly Approaches to Bioenergy Conversion. Sustainability 2024, 16, 3617. [Google Scholar] [CrossRef]
  63. Regueiro, L.; Carballa, M.; Álvarez, J.A.; Lema, J.M. Enhanced methane production from pig manure anaerobic digestion using fish and biodiesel wastes as co-substrates. Bioresour. Technol. 2012, 123, 507–513. [Google Scholar] [CrossRef]
  64. Rodriguez-Verde, I.; Regueiro, L.; Carballa, M.; Hospido, A.; Lema, J.M. Assessing anaerobic co-digestion of pig manure with agroindustrial wastes: The link between environmental impacts and operational parameters. Sci. Total Environ. 2014, 497–498, 475–483. [Google Scholar] [CrossRef]
  65. Gadirli, G.; Pilarska, A.A.; Dach, J.; Pilarski, K.; Kolasa-Więcek, A.; Borowiak, K. Fundamentals, Operation and Global Prospects for the Development of Biogas Plants—A Review. Energies 2024, 17, 568. [Google Scholar] [CrossRef]
  66. Esteves, E.M.M.; Herrera, A.M.N.; Esteves, V.P.P.; Morgado, C.D.R.V. Life cycle assessment of manure biogas production: A review. J. Clean. Prod. 2019, 219, 411–423. [Google Scholar] [CrossRef]
  67. Lijó, L.; Lorenzo-Toja, Y.; González-García, S.; Bacenetti, J.; Negri, M.; Moreira, M.T. Eco-efficiency assessment of farm-scaled biogas plants. Bioresour. Technol. 2017, 237, 146–155. [Google Scholar] [CrossRef]
  68. Fantin, V.; Giuliano, A.; Manfredi, M.; Ottaviano, G.; Stefanova, M.; Masoni, P. Environmental assessment of electricity generation from an Italian anaerobic digestion plant. Biomass Bioenergy 2015, 83, 422–435. [Google Scholar] [CrossRef]
  69. Sommer, S.; Petersen, S.; Møller, H. Algorithms for calculating methane and nitrous oxide emission from manure management. Nutr. Cycl. Agroecosystems 2004, 69, 143–154. [Google Scholar] [CrossRef]
  70. Wojcieszak, D.; Pawłowski, A.; Dammer, K.-H.; Przybył, J. Chemical and Energetical Properties in Methane Fermentation of Morphological Parts of Corn with Different Variety Earliness Standard FAO. Agric. Eng. 2023, 27, 273–287. [Google Scholar] [CrossRef]
  71. Derehajło, S.; Tymińska, M.; Skibko, Z.; Borusiewicz, A.; Romaniuk, W.; Kuboń, M.; Olech, E.; Koszel, M. Heavy Metal Content in Substrates in Agricultural Biogas Plants. Agric. Eng. 2023, 27, 315–329. [Google Scholar] [CrossRef]
  72. Minott, S.J.; Scott, N.R. Feasibility of Fuel Cells for Energy Conversion on Dairy Farms. In Proceedings of the 2001 ASAE Annual Meeting, California, CA, USA, 30 July–1 August 2001. [Google Scholar] [CrossRef]
  73. Wu, B.; Bibeau, E.L.; Gebremedhin, K.G. Three-Dimensional Numerical Simulation Model of Biogas Production for Anaerobic Digesters. In Proceedings of the 2006 ASABE Annual International Meeting, Portland, OR, USA, 9–12 July 2006; p. 51. [Google Scholar]
  74. Mulka, R.; Szlachta, J. State of knowledge concerning modelling anaerobic fermentation processes. Agric. Eng. 2013, 1, 281–290. Available online: https://yadda.icm.edu.pl/yadda/element/bwmeta1.element.ekon-element-000171339087 (accessed on 4 April 2024).
  75. Buivydas, E.; Navickas, K.; Venslauskas, K. A Life Cycle Assessment of Methane Slip in Biogas Upgrading Based on Permeable Membrane Technology with Variable Methane Concentration in Raw Biogas. Sustainability 2024, 16, 3323. [Google Scholar] [CrossRef]
  76. Eljamal, R.; Maamoun, I.; Bensaida, K.; Yilmaz, G.; Sugihara, Y.; Eljamal, O. A Novel Method to Improve Methane Generation from Waste Sludge Using Iron Nanoparticles Coated with Magnesium Hydroxide. Renew. Sustain. Energy Rev. 2022, 158, 112192. [Google Scholar] [CrossRef]
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Figure 1. Technological diagram of the analysed agricultural biogas plant [own elaboration]. 1—livestock facility, 2—slurry tank, 3—digester with biogas tank, 4—cogeneration unit, 5—digestate tank, 6—agricultural field.
Figure 1. Technological diagram of the analysed agricultural biogas plant [own elaboration]. 1—livestock facility, 2—slurry tank, 3—digester with biogas tank, 4—cogeneration unit, 5—digestate tank, 6—agricultural field.
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Figure 2. The course of the temperature variation of the digestion mass in the agricultural biogas plant under study.
Figure 2. The course of the temperature variation of the digestion mass in the agricultural biogas plant under study.
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Figure 3. Slurry flow recorded at the agricultural biogas plant under study.
Figure 3. Slurry flow recorded at the agricultural biogas plant under study.
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Figure 4. Fermenter mass height recorded at the agricultural biogas plant under study.
Figure 4. Fermenter mass height recorded at the agricultural biogas plant under study.
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Figure 5. Biogas level recorded at the agricultural biogas plant under study.
Figure 5. Biogas level recorded at the agricultural biogas plant under study.
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Figure 6. The course of active power P and reactive power Q variation was recorded at the agricultural biogas plant under study.
Figure 6. The course of active power P and reactive power Q variation was recorded at the agricultural biogas plant under study.
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Figure 7. Scatter plot of recorded values of substrate height (h) in the digester [m] and active power (P) [kW].
Figure 7. Scatter plot of recorded values of substrate height (h) in the digester [m] and active power (P) [kW].
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Figure 8. Scatter plot of the recorded values of the slurry flow (d) into the digester [m3] and the active power (P) [kW].
Figure 8. Scatter plot of the recorded values of the slurry flow (d) into the digester [m3] and the active power (P) [kW].
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Figure 9. Scatter plot of the recorded values of the biogas level (b) [m] and the active power (P) [kW].
Figure 9. Scatter plot of the recorded values of the biogas level (b) [m] and the active power (P) [kW].
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Figure 10. Scatter plot of the recorded values of the biogas level b [m] and the slurry flow (d) into the digester [m3].
Figure 10. Scatter plot of the recorded values of the biogas level b [m] and the slurry flow (d) into the digester [m3].
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Figure 11. Scatter plot of the recorded values of the slurry flow (d) into the digester [m3] and the temperature (t) prevailing in the digester [°C].
Figure 11. Scatter plot of the recorded values of the slurry flow (d) into the digester [m3] and the temperature (t) prevailing in the digester [°C].
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Figure 12. Scatter plot of the recorded values of the biogas height (b) in the digester [m] and the temperature (t) prevailing in the digester [°C].
Figure 12. Scatter plot of the recorded values of the biogas height (b) in the digester [m] and the temperature (t) prevailing in the digester [°C].
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Figure 13. Scatter plot of the recorded values of the substrate height (h) in the digester [m] and the temperature (t) prevailing in the digester [°C].
Figure 13. Scatter plot of the recorded values of the substrate height (h) in the digester [m] and the temperature (t) prevailing in the digester [°C].
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Figure 14. Scatter plot of the recorded values of the slurry flow (d) into the digester [m3] and the substrate height (h) in the digester [m].
Figure 14. Scatter plot of the recorded values of the slurry flow (d) into the digester [m3] and the substrate height (h) in the digester [m].
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Figure 15. Scatter plot of the recorded values of the biogas level (b) [m] and the substrate height (h) in the chamber [m].
Figure 15. Scatter plot of the recorded values of the biogas level (b) [m] and the substrate height (h) in the chamber [m].
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Table 1. Primary technical data on the generation equipment used in the agricultural biogas plant.
Table 1. Primary technical data on the generation equipment used in the agricultural biogas plant.
Internal Combustion Engine
TypeWG1605
Cycle Otto
Number of cylinders4
Displacement capacity1537 L
Rated speed2700 rpm
Rated active power20 kW
Rated apparent power26 kVA
Primary energy consumption62.5 kW
Thermal power40.9 kW
Flue gas temperaturemax 110 °C
Coolant temperaturemax 95 °C
Generator
TypeAsynchronous 4P/IE2
Rated speed1500 rpm
Rated frequency50 Hz
Rated voltage3 × 400 V
Winding connectiontriangle
Characteristics of the engine–generator group
Electrical efficiency32%
Total efficiency97%
Rated voltage400 V
Rated current29 A
Rated power factor (cos ϕ)0.97
Table 2. Results of statistical analysis between the studied quantities: h—height of substrate in the fermenter, d—flow of slurry into the fermenter, t—temperature of substrate, b—level of biogas, and P—active power generated by the agricultural biogas plant. Significant correlation coefficients for which p < 0.05 are shown in red.
Table 2. Results of statistical analysis between the studied quantities: h—height of substrate in the fermenter, d—flow of slurry into the fermenter, t—temperature of substrate, b—level of biogas, and P—active power generated by the agricultural biogas plant. Significant correlation coefficients for which p < 0.05 are shown in red.
VariableAverageStandard
Deviation		Correlations
hdtbP
h [m]1.64870.060391–0.025200–0.049520–0.096868–0.024616
d [m3]57.665710.04252–0.02520010.1742830.261175–0.137680
t [°C]36.00890.77989–0.0495200.17428310.1137220.003637
b [m]2.95090.41412–0.0968680.2611750.1137221–0.118963
P [kW]32.50843.78794–0.024616–0.1376800.003637–0.1189631
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Kuboń, M.; Skibko, Z.; Borusiewicz, A.; Romaniuk, W.; Gajda, J.S.; Kłosowska, O.; Wasąg, Z. Influence of the Parameters of an Agricultural Biogas Plant on the Amount of Power Generated. Appl. Sci. 2024, 14, 4200. https://doi.org/10.3390/app14104200

AMA Style

Kuboń M, Skibko Z, Borusiewicz A, Romaniuk W, Gajda JS, Kłosowska O, Wasąg Z. Influence of the Parameters of an Agricultural Biogas Plant on the Amount of Power Generated. Applied Sciences. 2024; 14(10):4200. https://doi.org/10.3390/app14104200

Chicago/Turabian Style

Kuboń, Maciej, Zbigniew Skibko, Andrzej Borusiewicz, Wacław Romaniuk, Jakub St. Gajda, Olivia Kłosowska, and Zbigniew Wasąg. 2024. "Influence of the Parameters of an Agricultural Biogas Plant on the Amount of Power Generated" Applied Sciences 14, no. 10: 4200. https://doi.org/10.3390/app14104200

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