Simulation and Optimization of Hot Dry Rock Geothermal Energy Conversion Systems: Process Conditions and Economics

摘要

The Los Alamos Scientific Laboratory is currently engaged in a field program aimed at designing and testing man-made geothermal reservoirs in hot granitic formations of low permeability created by hydraulic fracturing. A very important segment of the program is concerned with defining and optimizing several parameters related to the performance of the reservoir and their impact on the potential commercial feasibility of the hot dry rock technique. These include effective heat transfer area, permeation water loss, depth to the reservoir, geothermal temperature gradient, reservoir temperature, mass flow rate, and geochemistry. In addition, the optimization of the energy end use system (process or district heating, electricity or cogeneration) is directly linked to reservoir performance and associated costs. This problem has been studied using several computer modeling approaches to identify the sensitivity of the cost of power to reservoir and generation plant parameters. Also examined were a variety of important economic elements including rate of return on invested capital, discount or interest rates, taxes, cash flow, energy selling price, plant and reservoir lifetime, drilling and surface plant costs, and royalties. (ERA citation 04:010064)