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- Villarroel-Schneider, Johnny, et al.
(författare)
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Biogas based polygeneration plant options utilizing dairy farms waste : A Bolivian case
- 2020
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Ingår i: Sustainable Energy Technologies and Assessments. - : Elsevier. - 2213-1388 .- 2213-1396. ; 37
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Tidskriftsartikel (refereegranskat)abstract
- This study presents a comparative techno-economic feasibility analysis for two polygeneration plant solutions, applied to low-income dairy farms in Bolivia. The first option considers an internally fired microturbine (IFMT) and, the second, an internal combustion engine (ICE). They are integrated with an absorption refrigeration system and a fertilizer dryer. Biogas, produced with farms waste, fuels these power generators. The levelized costs of biogas for cooking, electricity, cooling and fertilizers were determined. The cost of biogas, for both options, was found to be 0.020 USD/kWh, which is lower than the subsidized price of LPG. The most competitive cost of electricity was determined for the ICE plant option; it was found to be 0.082 USD/kWh and is lower than the subsidized cost of fossil fuel-based electricity. The cost of cooling was found to be around 0.082 USD/kWh, which is slightly higher than the cost of cooling supplied by using grid electricity. In a realistic scenario, the shorter payback period was found to be 4.4 years for the ICE plant option. From this, the ICE-based plant was found as the most feasible option. Additionally, if no subsidies are applied to the fossil fuel-based services, the proposed polygeneration systems are a highly competitive alternative.
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| 2. |
- Villarroel-Schneider, J., et al.
(författare)
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Techno-Economic Study of a Biogas-Based Polygeneration Plant for Small Dairy Farms in Central Bolivia
- 2020
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Ingår i: Renewable Energy and Sustainable Buildings. - Cham : Springer. - 9783030184872 - 9783030184889 ; , s. 675-687
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Bokkapitel (refereegranskat)abstract
- This paper presents a techno-economic feasibility study of a polygeneration plant proposed for an association of dairy farmers in Bolivia. The systems have been designed in an integrated approach and are based on the resource recovery utilizing available cow dung. The production of biogas is proposed using “low cost” tubular digesters. The biogas is used for the production of electricity and heat in a 40 kWel internal combustion engine. Heat from the exhaust gas is recovered to drive an absorption cooling system for milk refrigeration and for a bio-slurry drying system. The final services are biogas, electricity, cooling and fertilizers. The techno-economic analysis focuses on determining the levelized cost of the services and compare them with the subsidized and non-subsidized prices of other competitive services in the market. Sensitivity analyses for the services prices are carried out to see the influence of the feedstock handling cost and the subsidies on investment capital. Once the selling prices of the services are defined, the payback period of investment capital is determined. The results show that the biogas and electricity costs were found lower than the subsidized prices of similar services in the market while the cost of cooling was found slightly higher. From the sensitivity analysis we have that the feedstock handling cost can be increased from 10 to 18 USD/ton while maintaining the biogas price below the subsidized LPG price, and applying subsidies to the investment capital allows reducing the rest of the services costs. The payback period is around 3.5 years when a subsidy of 15% is applied in the investment capital and the services are sold at the subsidized prices of the conventional services. Our study has shown that under the conditions of the Bolivian market it is feasible the installation of a polygeneration plant. On the other hand, a market without or with reduced subsidies for the conventional services makes the proposed system more feasible and competitive.
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