COAL BED METHANE – CONCENTRATED SOLAR POWER HYBRID SYSTEM POTENTIAL IN ZIMBABWE

2023-1
Mutume, Bruce
Despite the adverse environmental effects of fossil fuels, developing nations with inexpensive coal resources have difficulty switching to green energy. To ease the transition, natural gas is considered as the bridging fuel. Integrating conventional power plants (PP) with concentrated solar power (CSP) represents a more innovative strategy. To evaluate the feasibility of a gas-CSP hybrid, the North-Western region of Zimbabwe is chosen as the research area. The assessment's success is dependent on the following four essential aspects: (1) selecting a suitable location for both coal bed methane (CBM) and CSP; (2) CBM in-place volume and production estimation; (3) feasibility of CSP for an integrated solar combined cycle (ISCC) power plant; and (4) conducting a techno-economic and environmental analysis of the ISCC system. Using Monte-Carlo Simulation (MCS), the North-Western region OGIP estimated to range from 706 Bm3 to 5 699 Bm3. The Hwange-Lupane area was identified from the North-Western region as the zone with the most preferred conditions for CBM exploration. The Hwange-Lupane region's potential for CSP was investigated using a combination of the Geographic Information System and Analytic Hierarchy Process (GIS-AHP). Theoretically, Lupane's and Hwange's CSP potentials range from 1 207 to 1 613 TWh/year and 529 to 696 TWh/year, respectively. Zimbabwe has enough solar resources to switch to clean energy, as shown by the CSP potential found in this study. The Lupane region (the study area) was found to be the ideal location for the ISCC system by the GIS-AHP analysis. Accordingly, the CBM resources specific to Lupane are estimated and found to range from 250 to 1 400 Bm3. A Techno-economic and environmental analysis of a standalone CSP, Combined Cycle Gas Turbine (CCGT), and ISCC systems was carried out to validate the proposal. According to the results, the proposed ISCC PP only technically competes with the CCGT PP, where the latter generates electricity 7 % higher than the former, proving to be more sustainable than the use of standalone CCGT, CSP and coal-fueled PP. Regarding average cost ($) per kWh, comparable CSP, CCGT, and ISCC PPs have Levelized Cost of Electricity (LCOE) values of 0.178 $/kWh, 0.063 $/kWh, and 0.0581 $/kWh, respectively. Because its LCOE is the lowest, and it is also technically efficient and environmentally friendly, ISCC is proposed for transition to green energy. The feasibility of custom ISCC system was established by a resultant LCOE of 0.0728 $/kWh, less than Zimbabwe's retail cost of electricity (0.12 $/kWh) and cost of electricity generation (0.095 $/kWh).
Citation Formats
B. Mutume, “COAL BED METHANE – CONCENTRATED SOLAR POWER HYBRID SYSTEM POTENTIAL IN ZIMBABWE,” M.S. - Master of Science, Middle East Technical University, 2023.