Techno-Economic Analysis of Greenfield Geothermal Hybrid Power Plants using a Solar or Natural Gas Steam Topping Cycle

Technical Report · Fri Mar 29 04:00:00 EDT 2024

DOI:https://doi.org/10.2172/2352599· OSTI ID:2352599

Wendt, Daniel S. ^[1]; Neupane, Ghanashyam Hari ^[1]; Simpson, Juliet G. ^[2]; McTigue, Joshua ^[2]; Zhu, Guangdong ^[2]

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1. Idaho National Laboratory (INL), Idaho Falls, ID (United States)
2. National Renewable Energy Laboratory (NREL), Golden, CO (United States)

The relatively low generation costs associated with wind, solar PV, and natural gas power plants make it challenging for geothermal power plants to produce and sell the power that has the reliability and sustainability characteristics that are greatly needed in US power markets. This is especially true for geothermal resources with low to medium temperatures, which results in relatively low thermal efficiency and generation costs that are higher than those for wind, solar PV, and natural gas. This analysis evaluates solar thermal- and natural gas combustion waste heat recovery-based topping cycle hybridization of geothermal binary power plants. This approach provides several benefits that may allow geothermal power plants to generate power at more competitive costs. First, the addition of solar thermal energy or natural gas combustion waste heat input to a geothermal power plant provides additional heat input that can be converted to electrical power. Second, the temperature level of the heat obtained from concentrating solar collectors or natural gas combustion exhaust is higher than that of geothermal heat, which provides opportunities for improving the efficiency of the conversion of thermal energy to electrical power. Third, the ease with which solar thermal systems integrate with energy storage and the flexibility of natural gas means power generation can occur during peak demand periods.

• Research Organization: Idaho National Laboratory (INL), Idaho Falls, ID (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Geothermal Technologies Office
• DOE Contract Number: AC07-05ID14517
• OSTI ID: 2352599
• Report Number(s): INL/RPT--24-77205-Rev000
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
15 GEOTHERMAL ENERGY
20 FOSSIL-FUELED POWER PLANTS
concentrating solar power
geothermal power
hybrid power generation
natural gas combustion reciprocating engine power
natural gas combustion waste heat recovery
natural gas turbine power
thermal energy storage