Tashkent, Uzbekistan, 100084
Biomass energy utilization in the world and in the conditions of Uzbekistan
Biomass energy is one of the most promising types of renewable energy and is an important area for the development of sustainable energy sources, compared to traditional energy sources, including renewable energy sources. This type of energy is widely used in many countries, and Uzbekistan is not an exception.
Biomass is organic materials such as wood, agricultural waste, wastewater that can be used for energy production.
The biosphere is reported to contain 800 billion tons of biomass, 90% of the biomass is wood, of which 200 billion tons is renewable annually, equal to 100 billion tons of oil equivalent. The energy stored in biomass is equivalent in magnitude to fossil fuel reserves.
According to calculations, biomass is the least capital-intensive source of green energy. World biomass resources are estimated at 44·1010 EJ, but only 1/6 of this value is used. Currently, the share of energy derived from biomass is 15% of world consumption. This share is higher in developing countries, where it accounts for 38% of total energy production.
The following information on the installed capacity investment costs of HPP, NPP, SPP and WPP can vary depending on a number of conditions, including project location, technology, project scale and other factors. However, it is possible to provide typical estimates of installed capacity costs for each type of power plant, based on data from various sources.
1. Hydroelectric Power Plants (HPPs):
- Average construction costs can range from $1 million to $3 million per 1 MW of installed capacity, depending on the scale and conditions of construction. [Source: International Hydropower Association]
2. Nuclear power plants (NPPs):
- The cost of building a new nuclear power plant can vary, taking into account safety-related liabilities and various standards, but estimates range from $5 million to $9 million per 1 MW of installed capacity. [Source: Expert estimate according to the World Bank].
3. Wind Power Plants (WPP):
- The cost of installing wind turbines for VPPs can range from $1.3 to $2.2 million dollars per 1 MW of installed capacity. [Source: National Renewable Energy Laboratory].
4. Solar Power Plants (SPPs):
- The cost of installed solar capacity can range from $1.5 million to $2.5 million per 1 MW of installed capacity, depending on scale and technology. [Source: Solar Energy Industries Association]
5. Biogas power plants:
- Estimated project costs for installed capacity of a biogas power plant can range from 800 thousand to 1.5 million dollars per 1 MW of installed capacity, depending on size and region. [Source: World Biogas Association]
According to the International Energy Association, modern bioenergy is the largest renewable energy source in the world, accounting for 55% of renewable energy. The use of modern bioenergy increased by an average of about 7% per year between 2010 and 2021 and is on an upward trend.
According to the International Renewable Energy Association, the global installed bioenergy capacity in 2022 was about 148.9 GW, a 5% increase from 2021.
International agenda for biogas development
In June 2023, the Government of India launched an initiative to promote sustainable energy practices and the Ministry of Power announced a revision of the biomass co-firing policy. This revision will allow power plants to procure biomass pellets at base prices, reducing dependence on imports and promoting the adoption of biomass as a renewable energy source.
In June 2023, data compiled by the Energy Information Administration (EIA) showed that total compacted biomass fuel capacity in the United States reached 13.36 million tons in March 2023, with all of this capacity listed as currently operating or temporarily idle. Capacity included 1.96 million tons in the East, 10.51 million tons in the South, and 884,200 tons in the West.
In the global biogas market, the availability of sustainable feedstock for this purpose is expected to grow by 40% by 2040.
Figure 1 - Forecast of global biogas-based electricity generation, 2018-2040, Mtoe
The greatest opportunities are in the Asia-Pacific region, where natural gas consumption and imports have grown rapidly in recent years. Most biogas resources are currently more expensive to produce than the prevailing natural gas prices in the region, but the cost gap is projected to narrow over time. Europe and North America currently account for more than 60% of biogas production capacity. As the leading biogas producing region, Europe has about 20,000 biogas plants, most of which are located in Germany. Their installed capacity exceeds 7,000 MW. In countries such as Sweden, Finland, Austria, biogas accounts for 15-20% of total gas consumption. At the same time, the projected biogas production by 2040 may reach about 75 million tons per year. Figure 1 shows the forecast of biogas-based electricity generation for different regions of the world for 2018-2040 in Mtoe (1 Mtoe = 11.63TW*h).
Environmental impact of biogas and biogas energy
The energy use of biomass has an unfavorable impact on the natural environment. Direct combustion of wood releases a large amount of particulate matter, organic components, carbon monoxide and other gases into the environment. In terms of the concentration of some pollutants, they exceed the combustion products of oil and its derivatives. Another environmental consequence of wood combustion is significant heat losses.
Another issue is the potential environmental impact of biomass extraction and utilization. For example, wood extraction can lead to deforestation, which can have negative impacts on biodiversity and water resources. Also, biomass processing produces emissions of harmful substances such as carbon dioxide and methane, which contribute to climate change. The main adverse environmental impacts of bioenergy are listed below:
- emissions of particulate matter, carcinogenic and toxic substances, carbon monoxide, biogas, bioalcohol;
- heat emission, change of heat balance;
- depletion of soil organic matter, soil depletion and erosion;
- explosion hazard;
- large amounts of waste in the form of by-products (wash water, distillation residues).
Technologies and methods for obtaining energy from biomass
Several methods exist for utilizing biomass energy. One is the combustion of biomass to produce heat and electricity. Another method is biogasification, in which biomass is fermented to produce biogas that can be used as fuel. There are also biomass pyrolysis and hydrothermal treatment methods that produce fuels and chemicals from biomass.
Figure 2 - Biomass-to-energy conversion processes: general scheme
Pyrolysis is the most common method of producing energy from biomass (90% of the world's biomass energy production is due to the use of this technology) and is used for both heat and electricity production. Combustion boiler plants are suitable for processing various types of biomasses, mainly wood, wood chips, sawdust and straw. The process conducted at temperatures above 600℃ and without access to air, the output of which is liquid biofuel. The best feedstock for the pyrolysis process is wood, but since this technology is only at the beginning of its development, it can be assumed that any type of biomass can be converted in the pyrolysis process.
Gasification is a thermochemical conversion process that differs from combustion in that the product of the process is not heat, but a gas that provides the desired heat energy after combustion. Gas can also be used in special turbines to produce electricity. The advantage of gasification is the high efficiency of the process, up to 50%.
Cogeneration is the process of generating heat and electricity simultaneously. Cogeneration systems achieve lower pollutant emissions.
Biochemical processes - some forms of biomass containing large amounts of water are used in fermentation processes, where the product of biomass decomposition is alcohol, which is used for biofuel production. Methane fermentation processes are also used, the product of which is biogas (a mixture of methane and carbon dioxide). For energy purposes, animal manure, food industry waste, household waste from landfills and sewage sludge are used in the fermentation process.
Figure 3 - Scheme of energy production from biomass
There are many biogas plants in the world and the number is constantly growing. Some of the largest and best-known biogas plants in the world include:
1. Chia-Yueng-Tao (Chia-yi) in Taiwan - the largest biogas plant in the world, capable of processing an impressive 4,900 tons of organic material daily.
2. Lanhua in China - the second largest biogas plant in the world, using dry fermentation to treat about 4,000 tons of food waste daily.
3. Bilsthorpe in the United Kingdom - the largest biogas plant in Europe, treating about 120,000 tons of fermentable waste annually and producing up to 6.5 megawatts of electricity.
4. Milldale Anaerobic Wastewater Treatment Plant (Milldale) in the United States - the largest wastewater treatment and biomethane production plant in the United States with a capacity of up to 12,000 cubic meters of biogas per day.
5. Puxin Branded Biogas Plant in China - a popular small-scale plant used in agriculture to produce biogas from fermentable waste such as manure, straw and food waste.
Opportunities of Uzbekistan
Agriculture in Uzbekistan is the socio-economic basis of the population's livelihood. There are about 10,000 livestock farms in the country, as well as about 5 million citizens registered as engaged in raising animals and poultry in private subsidiary and dekhkan farms.
The livestock sector, while producing significant amounts of organic waste, potentially has resources for biogas production capable of replacing 6.4 billion m3 of natural gas per year (theoretical technical potential). If all biogas produced only from livestock waste is processed in biogas plants, it will allow generating more than 25.8 billion kWh of electricity per year, while producing 51.9 million tons of biological fertilizer. The waste produced on the territory of the Republic is sufficient for self-sufficiency of a significant part of the infrastructure of rural areas with electricity, generation of heat energy and fuel, as well as for obtaining its own high-quality organic fertilizers, which can provide high yields, restoring the natural productivity of the soil.
Experts of the Research Center “Ecoenergy” of the Ministry of Ecology, Environmental Protection and Climate Change of the Republic of Uzbekistan estimated the total technical potential of biomass in Uzbekistan at 3,500 MWh. The main feedstocks for biomass are cotton stalks (2-3 million tons/year), reeds (10-15 million tons/year), municipal solid waste (30 million m3/year) and agricultural waste (100 million m3/year). According to preliminary estimates, the available biomass resource potential in the country is 8.9 billion m3, which can meet 10% of the country's energy demand.
In conclusion, it can be assumed that the utilization of biomass energy offers us the opportunity to obtain sustainable and renewable energy. However, it is necessary to consider both positive and negative aspects of biomass use and take measures to minimize the negative impact on the environment. Further research and development of biomass may find more efficient and sustainable ways to utilize this energy source.
List of sources used
1. elar.urfu.ru/bitstream/10995/
4. https://trends.rbc.ru/trends/green/610a89709a7947d644d231bb
5. https://minenergy.uz/uploads/6bf5acea-12db-f746-1807-9469253e0fd9_media_.pdf
