Authors: Tanvir Ahmed Tonmay, Ghulam Mustafa, March, 2025
1 Description and History
1.1 Renewable Energy: An Overview
The need for energy and its related services to support human social and economic growth, welfare, and health is growing.1 Furthermore, overall industrial development has led to an exponential increase in global energy demand.2Fossil resources, particularly oil and natural gas are finite and should be viewed as diminishing assets, with efforts focused on discovering alternative sources of energy.3 It is well proven that fossil fuels are the major causes of pollution and global warming, which are primarily produced by the generation of CO2 and sulfur compounds. However, fossil fuels (such as coal, oil, and gas) are continuously used across the world due to technical, economic, and societal advancements. Recent energy crises, as well as the potential of rapidly depleting fossil or non-renewable fuel supply, have prompted industrialized countries to promote renewable energy production, distributed generation, and energy efficiency solutions. Access to renewable energy and other energy challenges are currently considered worldwide priorities for sustainable development.2
Renewable energy uses energy sources that are constantly replenished by nature, such as the sun, the wind, water, the Earth’s heat, and plants. Renewable energy technologies convert these fuels into useable forms of energy, often electricity, but sometimes heat, chemicals, or mechanical power.4 At present, renewable energy sources account for approximately 14% of global needs, although the development and use of renewable energy sources are expected to increase.5 Strong incentives have been created for the development of more competitive renewable energy production technologies by the European Union’s energy policy reform and the ensuing national laws and regulations. They have established several rules to help reach their objective of “no net greenhouse gas emissions by 2050”.2
1.2 Biomass: Introduction and Historical Perspective
Biomass is the plant materials produced by the reaction between carbon dioxide in the air, water, and sunlight via photosynthesis to produce carbohydrates, that serve as the building blocks of biomass.6 Biomass energy sources include wood and wood processing waste, such as firewood, wood pellets, sawdust, and black liquor from pulp and paper mills. Agricultural crops and waste materials like corn, soybeans, sugarcane, and food processing residues. Biogenic materials in municipal solid waste like paper, textiles, food waste, and yard waste. Additionally, animal manure and human sewage. Biomass can be converted to energy through various processes, including direct combustion (burning) to produce heat, thermochemical conversion to produce solid, gaseous, and liquid fuels, chemical conversion to produce liquid fuels, and biological conversion to produce liquid and gaseous fuels.7
Historically, biomass has been one of the oldest sources of energy, as early human civilizations relied on wood for cooking and heating purposes.6 There is a lot of evidence to support the claim that humans first used biomass as an energy source between 230,000 and 1.5 million years ago. Biomass existed long before humans were on Earth. Around the 19th century, we began to consider more modern applications of biomass resources. Here are some of the most common examples of biomass from the 19th century.8
- Ethanol, one of the first biofuels, originated from fermentation, and distillation was first documented in the 12thcentury in Italy. By the 1100s, it had been used for cooking and lighting. Ethanol is derived from biomass, primarily grains, and produced through fermentation and distillation, making it a readily available renewable fuel. In 1826, ethanol and turpentine were combined to power the first internal combustion engine. Its widespread use lasted until the late 19th century, indicating an important period in biofuel development.8
- As people began exploring ethanol’s potential as an alternative energy source, they also discovered that vegetable and fish oils could be used for heating and lighting. Historically, several civilizations, including the Egyptians and Sumerians, used animal and plant-based oils for combustion.8
- From the 1700s to the 1960s, pine sap was a precious renewable resource until the widespread use of petroleum. In its raw form, it played an important role in the shipbuilding sector. When distilled, the pine sap provided various important chemical compounds, with turpentine being the most significant. Turpentine had multiple applications, but its primary use as an alternative energy source was lamp oil.8
1.3 Biogas: Introduction and Historical Perspective
Biogas has a significant role to play in the worldwide energy transition because of the need to shift the global electricity networks from fossil fuel-based generation to low-carbon and renewable energy-based power production.9 Biogas is a combination of carbon dioxide, methane, and small quantities of other gases produced by anaerobic digestion of organic waste in an oxygen-free environment. The composition of biogas varies based on the feedstock and digestion conditions, but methane typically accounts for 45-75% of the mixture, with the majority of the remaining part being CO2. The energy content of biogas varies with a lower heating value (LHV) ranging from 16 to 28 MJ/m³ based on feedstock and digestion conditions. It can be used for numerical purposes, including electricity, heating, and cooking. Biomethane has an LHV of around 36 MJ/m³ almost similar to natural gas. So it can be used without any changes in transmission and distribution infrastructure and is suitable for natural gas vehicles.10 In 2018, more than 90% of the world’s biogas production was utilized to generate heat and electricity, with the remaining 9% either being injected into the natural gas grid or being used as biomethane in the mobility industry.11
Although biogas has gained popularity in recent decades, it has been utilized since the 10th century BC by the Assyrians to heat bathwater. Its origins were unknown until around 2,500 years later when Jan Baptist Van Helmont discovered that decaying organic matter produced combustible gasses. In the 1700s, Count Alessandro Volta related the amount of decomposing matter to the volume of gas produced, and in the early 1800s, Sir Humphry Davy recognized methane as the principal component.12
In 1859, the first anaerobic digester plant became operational in Bombay, India, and by 1895, biogas produced by a sewage plant in Exeter, England, was used for powering streetlights. In the year 1930, scientists identified anaerobic bacteria as the primary producer of biogas and identified the ideal conditions for producing methane. However, anaerobic digestion started to gain popularity in the 1970s as an alternative method of replacing fossil fuels. With the tremendous increase in demand for renewable energy in the twenty-first century, anaerobic digestion developed as an alternate way to meet increasing decarbonized energy demand and global methane reduction targets.12
2 Economic Performance
The global population has grown by roughly 1 billion per decade over the last half-century, and it is expected to reach 10 billion by 2050. Rapid population growth, along with a volatile global economy and escalating trade tensions between key power centers, needs more food production and novel solutions at the intersection of the food industry and biowaste management.13 The economic viability of biomass and biogas production is a crucial factor in their development as alternative energy sources. Agriculture remains the primary economic activity for more than two-thirds of the world’s population, in addition to playing a critical role in food production.14
2.1 Economic Feasibility Foundations
The economic feasibility of biomass and biogas is generally evaluated in terms of technology and fuel costs, as well as financial constraints specific to each region. Developing countries face higher electricity costs due to outdated infrastructure and limited access to advanced bioenergy technologies. In contrast, agricultural economies benefit from lower feedstock prices due to abundant biomass, making bioenergy a more feasible alternative to fossil fuels. Using forest biomass for bioenergy can increase national revenue while also helping reduce poverty by lowering fossil fuel import bills.14
2.2 Supply Chain and Logistics Considerations
Several economic considerations influence the viability of biomass utilization. One of the main concerns is its low energy density, which means higher transportation and delivery costs to refinery plants. Furthermore, biomass feedstocks are spread across broad areas, making collection costly and logistically challenging. Pretreatment procedures like drying and pyrolysis increase production costs by reducing moisture content and increasing energy density. Another important consideration is the seasonal variability of biomass, which demands careful planning and scheduling to ensure continuous supply and quality. These constraints highlight the need for an efficient supply chain network in making biomass-to-bioenergy conversion commercially viable.15
2.3 Factors Affecting Economic Sustainability
The economic sustainability of biogas production extends beyond mere profit generation and is influenced by multiple factors:
- Availability, accessibility, and properties of input materials
- Ongoing expenses for maintenance and system operation
- Production and application of byproducts
- Necessary to maintain long-term economic viability.9
2.4 Historical Evolution of Technology Costs
The costs of biogas and biomass technologies have shown significant evolution over the past decade. According to IRENA data, the global weighted average LCOE for bioenergy has decreased by approximately 14% between 2010 and 2023. However, this cost reduction has been less dramatic than other renewable energy sources. During the same period (2010-2023), solar PV costs fell by 90% and onshore wind by 70%.16
2.5 Levelized Cost of Electricity (LCOE) Comparison with Alternatives
The LCOE provides a standardized mechanism for comparing various sources of electricity generation. According to the International Renewable Energy Agency (IRENA), the global weighted average LCOE for bioenergy in 2023 was at $0.072/kWh. This data shows that bioenergy (including biogas and biomass) is more expensive than solar PV, onshore wind, geothermal, and hydropower, but it is still cost-competitive with offshore wind and conventional fossil fuels.16
2.6 Capital Expenditure Trends
The initial investment costs for biogas and biomass facilities vary significantly based on scale and technology:
The CAPEX for bioenergy installations has decreased over time, with costs in 2010 averaging approximately $3010/kW compared to $2730/kW in 2023, representing a 9% reduction.16 This decrease is primarily attributed to technological maturation, improved manufacturing processes, and increased competition among technology providers.
2.7 Cost Competitiveness for Electricity Generation
Despite its higher cost than natural gas, wind, or solar energy, biomass-powered electricity generation is growing. However, it is much cheaper than new coal or nuclear power plants. Compared to coal and natural gas, biomass power generation emits intermediate levels of NOx and SO2 per MWh produced.17 Traditional electricity sources face multiple challenges, including fuel price fluctuations, seasonal variations in hydropower, fluctuation issues in wind and solar energy, longer project delivery timetables for geothermal power, and security risks associated with nuclear power generation.9
2.8 Market Size and Growth Projections
The biogas and biomass sectors are experiencing notable growth, driven by increasing demand for renewable energy and advancements in technology:
- Biogas Market: The global biogas market size was USD 133.61 billion in 2024 and is expected to grow from USD 140.89 billion in 2025 to USD 191.19 billion by 2032 at a CAGR of 4.46% during the forecast period. Europe dominated the global market with a share of 53.6% in 2024.18
- Biomass Market: The biomass market is projected to register a CAGR of 7.12%, reaching approximately $82.59 billion by 2030. Factors contributing to this growth include the availability of raw materials and increasing demand for biomass energy across various end-use sectors.19
These trends indicate a positive outlook for the adoption of biogas and biomass as integral components of the global renewable energy landscape.
2.9 Key Challenges in Shifting Toward a Bio-Based Economy
A bio-based economy has been recognized as a viable solution to both environmental and economic issues. Industrialists and other stakeholders, including economists, have focused efforts on transitioning from a fossil-based to a bio-based economy. However, the transition to a bio-based economy is hindered by challenges and limitations.20
- Scale and Capacity Limitations: Currently, the bio-based economy is limited to small-scale production. Capacity enhancement is a challenge that must be addressed if the future energy mix is bio-based.20
- Resource Allocation Concerns: Another issue under debate is the availability of biomass/biowaste to meet the bioenergy demand. Dedicating arable land for bioenergy production may reduce the share of food crops, leading to food insecurity. The current food vs. fuel discussion (for example, should biomass be used as a fuel?) affects the overall use of biomass and consequently affects policy development.20
- Production Economics and Transportation: Biofuel production and transportation, particularly over long distances, are essential for developing a bio-based economy. The per-unit cost of biofuel production must be reduced to compete with fossil fuels. This issue can be resolved by adopting and promoting the latest technology to reduce overall costs.20
- Skills and Expertise Gap: The lack of skills and expertise needed to exploit bioenergy resources significantly hinders the development of the local bioenergy industry.20
3 Ecological Performance
The increasing urgency to address climate change and reduce dependency on fossil fuels has accelerated the search for sustainable energy solutions. Among the most feasible alternatives are biomass and biogas, both renewable energy sources derived from organic substances. Biomass and biogas have tremendous promise to reduce greenhouse gas (GHG) emissions, waste management, and develop sustainable energy systems.21 The ecological performance of these energy systems is an important component in determining their sustainability. For example, biogas production produces renewable energy and reduces methane emissions from decomposing organic waste.22 Although biomass is a resource of renewable energy, its impact on the environment remains a concern, particularly regarding deforestation, land-use changes, and combustion-related air pollution. However, biomass can be a key component in lowering carbon emissions and advancing energy security if it is procured responsibly and handled effectively.23
Globally, biogas and biomass help to achieve Sustainable Development Goals 7 (Affordable and Clean Energy) and 13 (Climate Action). Countries such as Germany and Sweden have integrated biogas into their waste management systems, significantly decreasing methane emissions from landfills. According to the International Energy Agency (IEA), biogas production has the potential to decrease methane emissions by up to 80%, supporting climate mitigation efforts.24
3.1 Carbon Footprint and Greenhouse Gas Emissions
Biogas production significantly decreases methane emissions by capturing methane from organic waste, which would otherwise be discharged into the environment. Biogas combustion produces 50-70% less CO₂ per kWh than coal and eliminates sulfur dioxide (SO₂). Methane is an extremely potent greenhouse gas that has the potential to cause global warming around 28-34 times higher than carbon dioxide over 100 years. The transformation of organic waste into biogas helps to minimize climate change and reduce carbon footprint.25 The carbon neutrality of biogas is further improved by using digestate, the byproduct of anaerobic digestion, as a nutrient-rich biofertilizer. This practice decreases reliance on chemical fertilizers, which are energy-intensive to manufacture, hence cutting greenhouse gas emissions. Biogas generation contributes to a closed-loop system that exemplifies circular economy concepts by converting biological waste into useful resources while supporting sustainable energy and recycling of nutrients.22
When biomass is sourced sustainably, the carbon dioxide (CO2) emitted during burning is balanced by the CO2 absorbed during biomass growth, making it carbon-neutral. This balance is maintained by growing new biomass at the same pace as it is consumed, resulting in low net emissions. However, improper harvesting practices can result in deforestation and increased carbon dioxide emissions, undermining the environmental advantages. For example, converting forests to biomass plantations might create a “carbon debt” that may require decades to repay.26 Furthermore, the carbon footprint of biomass energy is highly dependent on the type of feedstock and the efficiency of the converting procedure. For example, Woody biomass has a lower carbon footprint than agricultural leftovers because it has a higher energy density and less moisture. Advanced technologies like carbon capture and storage (CCS) may further decrease the carbon emissions connected with biomass energy, making it a more environmentally friendly option.27
3.2 Biodiversity and Land Use
The ecological performance of biomass is heavily dependent on land use practices. Large-scale monoculture systems for biomass feedstock cultivation can lead to reduced biodiversity, soil degradation, and water scarcity. To reduce environmental consequences and promote ecosystem health, sustainable biomass production necessitates integrated land management strategies such as agroforestry and diverse cropping systems.28 Furthermore, using marginal lands for biomass cultivation can reduce conflict between food and energy production while repairing deteriorated soils. Perennial grasses, such as switchgrass and miscanthus, can be produced on marginal soils, providing a sustainable source of biomass without compromising food security.29 Agroforestry systems, which include trees, crops, and livestock, can improve biodiversity and soil conditions while providing biomass feedstock. These technologies not only promote sustainable cultivation of biomass but also help to mitigate climate change through carbon sequestration.30
Biogas generation from organic materials, such as crop residues and manure, is a sustainable alternative that avoids conflicts between land use and biodiversity loss. To ensure the long-term viability of biogas production, it is essential to balance feedstock availability with ecosystem health. However, relying solely on energy crops for feedstock can result in habitat loss and soil degradation. To minimize ecological impacts, sustainable biogas systems should prioritize waste-based feedstock and integrate diversified cropping practices. Proper digestate management is also essential to prevent nutrient runoff and water pollution.31
3.3 Air Quality and Pollution Control
Biogas combustion emits up to 90% less particulate matter (PM2.5) and 50% less nitrogen oxides (NOₓ) compared to coal, making it a cleaner alternative to fossil fuels. This considerable reduction in pollutants helps to improve air quality and public health, especially in areas transitioning away from coal and diesel reliance. In developing countries, the use of clean cookstoves utilizing biogas has been demonstrated to decrease indoor air pollution by 60-80%, addressing a key health problem and decreasing the incidence of respiratory illnesses. Furthermore, using biogas in CHP (combined heat and power) systems improves energy efficiency and decreases greenhouse gas emissions when compared to traditional energy systems, making it a viable option for both rural and urban energy demands all over the world.32
Biomass combustion can emit pollutants such as carbon monoxide and volatile organic substances if it is not properly controlled. Modern technologies, like as gasification and pelletization, have been invented to reduce these emissions and enhance the environmental sustainability of biomass energy systems globally. Sustainably sourced biomass used in industrial operations can decrease carbon dioxide emissions by up to 40% in comparison to fossil fuels. However, the ecological effect of biomass changes with feedstock type and burning procedures. The current study continues to increase combustion effectiveness and minimize lifecycle emissions so that biomass remains a sustainable energy source.33
3.4 Evolution of Ecological Performance Over Time
Biogas:
- 1980s–2000s: Early biogas systems were unproductive, leaking 20-30% of the methane produced. Modern anaerobic digesters currently collect 60-80% methane, greatly lowering emissions.34
- 2010s–Present: The co-digestion of food waste with manure has enhanced biogas outputs by 30-50%, improving resource productivity and waste valorization [14]. Policies, such as the EU Renewable Energy Directive II, have further pushed sustainable feedstock utilization.35
Biomass:
- Pre-2000: Biomass depended on open combustion and deforestation, generating 5 to 10 times more particulate matter compared to the current systems.36
- Post-2010: Advanced methods such as palletization and gasification have reduced emissions by 80%, while second-generation biofuels now utilize non-food biomass, decreasing land-use competition.37
4 Social Impact
Social acceptance of bioenergy has emerged as a critical aspect in shifting from nonrenewable to renewable energy. However, public knowledge and awareness of bioenergy remain low compared to solar and wind energy. Many European countries resist bioenergy due to conflicts and a lack of social actors’ participation in decision-making, which alters priorities and limits application success.38 The level of social acceptance for biogas as a renewable energy source is often overlooked. Although several projects have concentrated on the development of new biogas facilities around the world, local objections are not uncommon. How consumers, citizens, and workers participate in the new circular economy has a mutual impact on social acceptance and new circular business models, which could involve renewable energy.39 The evolution of social acceptance for biogas technologies has followed a complex trajectory over time. Early biogas adoption in the 1970s and 1980s was primarily driven by energy security concerns rather than environmental benefits, with limited public engagement. Since the early 2000s, acceptance has improved in countries with strong policy support and educational initiatives.40
4.1 Positive Social Impacts
- Job Creation: The primary social benefit of biogas technology is that it generates job opportunities for both qualified and unskilled workers. Biofuels create numerous job opportunities, including biomass cultivation and harvesting, transportation, plant management, equipment manufacturing, and maintenance.41 Employment opportunities are also created in the design, manufacture, operation, and maintenance of biogas equipment and appliances. China has more than 90,000 individuals working directly or indirectly in biogas-related employment, while Germany and India have 85,000 and 50,000, respectively.9 Total renewable energy jobs globally in 2023 reached 16.2 million, up from 13.7 million in 2022. Globally, there were 2.8 million biofuel jobs in 2023, with the bulk in the agricultural supply chain. Brazil has the largest number of jobs (994,000), followed by Indonesia (798,600).42
- Energy Access and Poverty Alleviation: Decentralised bioenergy production is a significant driver of increased access to modern, clean, and inexpensive energy, particularly in rural areas. Nearly a billion people in these places do not have access to power. This can speed up the development of circular integrated food and energy systems.43Efficient bioenergy production in rural areas can provide affordable energy, improving public health and education while reducing poverty.44 The governments of India and China have been advocating household biodigesters as a rural energy source for decades. This provides a major incentive for farmers to channel organic residues, waste, and manure through the biodigester to obtain both biogas as an energy source and organic fertilizer for their agricultural fields.43
- Environmental and Community Stability: The use of biogas minimizes the environmental impact of organic waste, which can otherwise be a source of conflict among neighbors. Biogas lamps provide a clean source of affordable light, benefiting schoolchildren who can use it for studying and homework. In rural areas of developing countries, women and children spend long hours collecting firewood, leading to deforestation. Biogas reduces this burden and improves social relations and well-being.9 The Food and Agriculture Organization of the United Nations regards the integration of renewable energy production into rural smallholder farming systems as vital for the provision and sustenance of rural livelihoods and the sustainable improvement of agricultural production systems. ‘Integrated Food and Energy Systems’ (IFESs) are based on the principles of sustainable production intensification. Agricultural productivity is maximized through high agrobiodiversity while maintaining the productive capacity of the overall land-use system.43
An example of an IFES is the ‘livestock-biogas-fruit system’ developed in Guangdong, South China. Orchard residues and pig manure form the feedstock for biodigesters located under the pig stables. The digester provides biogas as a clean energy source and organic fertilizer. The latter, in turn, improves soil fertility and reduces mineral fertilizer inputs. Further, chickens roam in the orchards, feeding on weeds and pests, decreasing pesticide application and additionally providing manure for bio digestion.43
4.2 Negative Social Impacts
- Community Resistance and Social Conflict: Protests against new biogas plants are common due to concerns over social acceptability and business models.39 In the case of bioenergy, local opposition has become a precarious issue for many projects, potentially causing delays and interrupting operations. The reasons of local opposition are mostly rooted in perceived injustice regarding the decision-making process and the sharing of burdens and benefits. Local residents in particular have to cope with changes in their living environment because of odor and noise emissions induced by the plant.45
- Health Concerns: Workers and populations near biogas plants could be exposed to pollutants such as nitrogen dioxide, Sulfur dioxide, bacteria, fungi, and endotoxins.46 The main greenhouse gases produced by biogas include carbon dioxide (CO₂), methane (CH₄), and nitrogen oxide (N₂O), raising environmental and health concerns.9Failures of biogas installations have caused deaths and injuries in the past. In 2005, Germany witnessed an accident where hydrogen Sulphide was released in a plant loading bay due to non-compliance with health and safety regulations, leading to four deaths and one hospitalization. Hydrogen Sulphide, being highly toxic, poses a significant hazard to human health and life even at low concentrations.47
- Land Use & Environmental Issues: The utilization of marginal land is often linked to negative social-ecological impacts such as biodiversity losses, environmental pollution, and a decrease in the recreational value of landscape.43
Bioenergy crop production influences biodiversity mainly through changes in land use (crop types and intensification) and land cover, which potentially result in habitat loss and fragmentation.43
5. Political and Legal Aspects
Political and regulatory frameworks, including the laws, legislation, and incentives that governments use to encourage renewable energy sources, heavily drive the advancement and spread of biogas and biomass technologies.35 Policy measures are critical in overcoming hurdles to implementing renewable energy, such as high initial prices, technological problems, and competition in the market with fossil fuels.24 This section will explore both the political and legal aspects of biogas and biomass, focusing on significant policies, their consequences, and the benefits and drawbacks of various approaches.
Key Policies Shaping the Biogas and Biomass Development
5.1 Renewable Energy Directives (RED) in the European Union
The European Union’s Renewable Energy Directive (RED) has been playing a key role in promoting biogas and biomass as renewable energy sources. RED established obligatory objectives for all EU member courtiers to reach a 20% renewable energy share of total energy consumption by 2020, which was later boosted to 32% by 2030 under RED II (European Commission, 2018). This policy has resulted in major investments in biogas and biomass technology across Europe.48
5.2 Feed-in Tariffs (FiTs) in Germany
Germany’s Renewable Energy Sources Act (EEG) introduced the Feed-in Tariffs (FiTs) to encourage the generation of renewable energy, such as biogas and biomass. Under this policy, energy producer will receive a fixed payment for the electricity they feed into the grid, which promotes financial stability and encourages investment in renewable energy technology. This policy has been extremely effective, with Germany running over 9,000 biogas plants by 2020, strengthening its position as a global leader in biogas generation.49
5.3 The Renewable Fuel Standard (RFS) in the United States
The United States Renewable Fuel Standard (RFS) is a government program that mandates the incorporation of renewable fuels, such as biogas and biomass-derived fuels, into the country’s transportation fuel supply chain. This policy has significantly contributed to the expansion of the biogas sector, notably the generation of renewable natural gas (RNG) from organic waste products.50
5.4 National Biogas and Organic Manure Programme in India
The National Biogas and Organic Manure Programme of India intends to increase biogas production for cooking and power generation in rural regions. The program grants financial incentives for the establishment of biogas plants, resulting in the construction of approximately 5 million plants around the country. These plants contribute to sustainable agriculture and rural livelihoods by producing organic manure in addition to renewable electricity.51
5.5 China’s Biogas Development Policy
China has established large-scale biogas development initiatives as part of its renewable energy and rural development goals. The National Biogas Construction Plan encourages the development of household and industrial biogas plants, particularly in rural regions, to reduce energy poverty and decrease dependency on coal. By 2020, China has installed more than 40 million domestic biogas digesters, which makes it one of the largest biogas marketplaces worldwide.24
Pros and Cons of Alternative Policies
5.6 Feed-in Tariffs (FiTs) vs. Renewable Portfolio Standards (RPS)
Feed-in Tariffs (FiTs) provide assured payments to renewable energy suppliers, promoting financial stability and investment. This can result in increased energy bills for customers. Besides, Renewable Portfolio Standards (RPS) require companies to get a specific amount of their energy from renewables, encouraging competition and perhaps cutting prices. On the other hand, RPS doesn’t allow the same amount of financial assurance to producers.52
5.7 Subsidies vs. Carbon Pricing
Subsidies for biogas and biomass plants can help to drive technological adoption, but they can also strain government resources. Carbon pricing, which includes carbon taxes or cap-and-trade systems, internalizes the negative environmental impacts associated with fossil fuels, making renewable energy more viable. However, carbon pricing can face political opposition and may negatively impact low-income households.53
5.8 Mandates vs. Voluntary Programs
Mandates, like the Renewable Fuel Standard (RFS) in the United States, assure a minimum amount of renewable energy consumption by legally enforcing compliance, but that can be inefficient and difficult to adjust when market conditions shift. In contrast, voluntary initiatives, such as green energy certification schemes or corporate renewable energy commitments, provide more freedom and stimulate innovation by enabling participants to adopt renewable energy at their own speed. However, voluntary initiatives may not achieve the same widespread acceptance or impact as requirements, as they rely on individual or organizational desire rather than governmental enforcement.24
Political and regulatory frameworks play an important role in shaping the growth and diffusion of biogas and biomass technology. Policies like the EU’s Renewable Energy Directive (RED), Germany’s Feed-in Tariffs (FiTs), the United States’ Renewable Fuel Standard (RFS), India’s National Biogas and Organic Manure Programme (NBMMP), and China’s National Biogas Construction Plan (NBCP) have made a significant impact on the growth of these technologies. These policies not only encouraged the utilization of biogas and biomass, but they also addressed major problems such as energy poverty, rural development, and greenhouse gas emissions.24,48-51
However, the selection of policy instruments includes trade-offs. Feed-in Tariffs (FiTs) provide financial stability for producers, but they can raise utility costs for consumers.52 Similarly, subsidies may hasten technological adoption but strain government budgets and carbon pricing can encourage renewable energy use but may create political issues. Therefore, the effectiveness of these policies and regulations depends on their design, execution, and adaptation to the local context.53
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