Abstract
The limitation of fossil resources and the environmental impacts resulting from their combustion have increased the importance of using renewable energies, including biomass energy. One of the approaches to energy production from biomass is the simultaneous generation of electricity and heat from animal manure. Given the substantial share of animal manure in biomass resources and its improper management in the country, it is essential to evaluate the potential for bioenergy production and to determine the spatial distribution of this renewable resource in different regions of Iran. Accordingly, the present study was conducted to assess the feasibility of bioenergy production from animal manure in Lorestan Province. The data required for this research were collected from relevant organizations, library resources, and the Agricultural Statistics Yearbook for the year 1402 (2023–2024). Based on the results, the total amount of collectable animal manure in the province was estimated at 355,069.7 tons, and the amount of methane produced from it was calculated to be 54.319 million cubic meters. The electrical and thermal energy and power outputs of the combined heat and power (CHP) system from animal manure were obtained as 236,287.68 MWh of electricity with a power of 33.75 MW and 265,823.62 MWh of heat with a power of 37.96 MW, respectively. The counties of Khorramabad, Borujerd, and Aligudarz ranked first to third in the province, with electricity generation potentials of 41,781.75, 38,335.68, and 32,695.04 MWh, and thermal energy generation potentials of 47,004.47, 43,127.64, and 36,781.91 MWh, respectively. In addition, the global warming potential index associated with energy production from animal manure was calculated to be 118,274.74 tons of CO₂ equivalent. According to the results, the use of electricity generated from animal manure can supply 7.11% of the total electrical energy consumption in Lorestan Province.
EXTENDED ABSTRACT
Introduction
Population growth and technological advancement mean that human activities now consume high levels of energy. This causes significant problems, including the depletion of fossil fuel resources and environmental pollution. Energy managers and planners are therefore developing options to meet these increasing demands for energy while maintaining a low environmental impact. The application of advanced energy-saving techniques, renewable energy resources, and technologies presents a viable solution to these problems. Bioenergy is a widely available resource, making it an attractive form of renewable energy. Biomass is abundant and easily accessible, making it a low-cost resource with great flexibility in terms of potential applications. One effective way to harness biomass energy is through the simultaneous production of electricity and heat from animal waste. Cogeneration, a highly efficient technology, produces both electricity and thermal energy using a variety of technologies and fuels, offering a cost-effective solution to reduce CO2 emissions. Given the significant amount of animal waste in biomass resources and its inadequate management in the country, it is crucial to assess the potential for bioenergy production and analyze the distribution of this renewable resource across different regions of Iran. This research aims to evaluate the bioenergy production potential from animal waste in Lorestan province.
Material and Methods 
Data for this study were gathered from relevant organizations, library sources, and agricultural statistics for the year 2023. This section of the research focuses on the geographical location of the region, livestock and poultry data, the amount of animal waste, methods for calculating the theoretical and potential for biogas and methane production from animal waste, the examination of simultaneous electricity and heat production, and the estimation of pollutant emissions from bioenergy production using animal waste. Finally, the share of reducing the production of electric energy from fossil fuels by replacing the electric energy produced from animal waste in Lorestan province was calculated.
Results and Discussion 
Based on the results, the amount of waste that can be collected from much livestock in the province was calculated to be 280318.6 tons, and heavy (cow) and light (sheep and goat) livestock with a production amount of 152594.9 and 127723.7 tons, respectively, accounted for 54.44% and 45.56% of the waste that can be collected from much livestock, respectively. Additionally, the amount of waste that can be collected from poultry units in the province was estimated to be 74,751.1 tons. Broiler and egg-laying chicken breeding units, with production amounts of 68,626.3 and 6,124.8 tons, respectively, accounted for 91.81% and 8.19% of the waste from poultry units. The annual methane production potential from livestock and poultry waste in the province was calculated to be 34.136 and 20.183 Mm3, respectively. Additionally, the total amount of animal waste (from livestock and poultry) that can be collected in the province was estimated at 355,069.7 tons, and the annual amount of methane produced from it was estimated at 54.319 Million Cubic Meters. Khorramabad, Borujerd, and Aligudarz counties were ranked first, second, and third in the province, with annual production potentials of 9.605, 8.813, and 7.516 Mm3, respectively.
Additionally, the energy, electrical, and thermal power of the CHP (combined heat and power) system derived from animal waste were calculated as 236,287.68 MWh of electricity with a power of 33.75 MW and 265,823.62 MWh of heat with a power of 37.96 MW, respectively. Khorramabad, Borujerd, and Aligudarz counties were ranked first, second, and third in the province, with the potential to produce 41781.75, 38335.68, and 32695.04 MWh of electricity, and 47004.47, 43,127.64, and 36,781.91 MWh of heat, respectively. The amount of greenhouse gas emissions from the production of electrical energy from animal waste was 118,148.45 tons/year, and the share of CO2, N2O and CH4 in the emissions was 118,143.84, 0.1181, and 4.49 tons/year, respectively. Additionally, the global warming potential (GWP) index for energy production from animal waste was calculated to be 118,274.74 tons of CO2 equivalent. Compared to gas-fired power plants, generating electricity from animal waste reduces greenhouse gas emissions by 64,309.01 tons of CO2 equivalent/year (35.2%).
Conclusions 
The current significant dependence of the energy sector on fossil fuel resources has led to numerous problems worldwide, including energy security issues and environmental pollution. Many abandoned renewable resources could be utilized to generate energy and balance the energy consumption profile in this sector. One of the energy sectors that significantly relies on fossil fuels is the electricity generation sector. In addition, one of the most overlooked renewable sources of biomass originates from the agriculture sector, i.e., animal waste. Hence, the present study aimed to assess the potential for bioenergy production from animal waste in Lorestan province. Based on the results, the use of electrical energy produced from animal waste can supply 7.11% of the electrical energy consumed in Lorestan province. Therefore, by producing bioenergy from animal waste, we can take steps to reduce dependence on fossil resources and greenhouse gas emissions, and thus achieve sustainable development.
Acknowledgements
"Not applicable"
Author Contributions
Movahed Sepahvand: Conceptualization, Methodology, Software, Validation, Formal analysis, Data curation, Writing-original draft preparation, Writing-review and editing, Supervision, Project administration.
Hadis Nematpour Malek Abad: Conceptualization, Methodology, Formal analysis, Resources, Writing-original draft preparation.
Mohammad Ali Ghahremani Aghbolagh Rostam Khan: Methodology, Formal analysis, Resources.
Data Availability Statement
The original contributions presented in the study are included in the article; further inquiries can be directed to the corresponding author.
Ethical Considerations
The authors avoided data fabrication, falsification, plagiarism, and misconduct.
Conflict of Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Funding Statement
The author(s) received no specific funding for this research.