Geothermal

The Geothermal Power model represents a power plant that uses heat from below the surface of the ground to drive a steam electric power generation plant. SAM does not have a model for ground source heat pumps for residential and commercial building applications.

Geothermal Power Videos

GETEM in the System Advisor Model (SAM)

This webinar introduces the updates to SAM's Geothermal Power model based on updates to the Geothermal Electricity Technology Evaluation Model (GETEM).

Supporting materials:

Geothermal Power

SAM's geothermal power model is based on the U.S. Department of Energy's Geothermal Electricity Technology Evaluation Model (GETEM), https://www.energy.gov/eere/geothermal/geothermal-electricity-technology-evaluation-model. The model calculates the annual and lifetime electrical output of a utility-scale geothermal power plant, and the levelized cost of energy and other economic metrics for the plant.

SAM cannot model a ground source heat pump (also called geothermal heat pump or geoexchange) systems for building heating and cooling.

The geothermal power model calculates the output of a power plant that uses heat from below the surface of the ground to drive a steam electric power generation plant. SAM analyzes the plant's performance over its lifetime, assuming that changes in the resource and electrical output occur monthly over a period of years.

SAM can be used to answer the following kinds of questions:

  • What is the levelized cost of a geothermal power plant, given a known configuration and resource?
  • How does changing the design of the plant affect its output and levelized cost of energy?
  • What plant size is required to meet an electric capacity requirement?
  • Given a known number of wells, what would the plant's electric capacity be?

SAM models the following types of systems:

  • Hydrothermal resources, where the underground heat reservoir is sufficiently permeable and contains sufficient groundwater to make the resource useful without any enhancements.
  • Enhanced geothermal systems (EGS) that pump water or steam underground to collect heat stored in rock. These systems involve drilling or fracturing the rock to improve heat transfer. Over time (typically years), as heat is collected from the rock, its temperature decreases, and more drilling is required. SAM's recapitalization cost accounts for the cost of these improvements to reach new resources.
  • Both flash and binary conversion plants.

Geothermal Publications

Akindipe, D.; Witter, E.; Prilliman, M.; Mirletz, B.; Ho, J.; Trainor-Guitton, W.; Pinchuk, P.; Williams, T. (2024). Geothermal Power Systems Analysis: Outcome of Industry Stakeholders Workshop. Geothermal Rising Conference, Waikoloa Hawai'i. NREL/CP- 5700-90784. (PDF 688 KB)

Prilliman, M. (2023). GETEM in the System Advisor Model (SAM). Conference presentation. NREL/PR-7A40-85131. (PDF 2.2 MB)

Robins, J.; Kesseli, D.; Witter, E; Rhodes, G. (2022). 2022 GETEM Geothermal Drilling Cost Curve Update.

Augustine, C. (2017). A Methodology for Calculating EGS Electricity Generation Potential Based on the Gringarten Model for Heat Extraction From Fractured Rock. NREL/CP-6A20-66485.

Hanson, S. (2013). Geothermal Electricity Technology Evaluation Model (GETEM) Individual Case Files and Summary Spreadsheet (GETEM version Spring 2013).

Mines, G. (2008). Geothermal Electricity Technologies Evaluation Model DOE Tool for Assessing Impact of Research on Cost of Power.

Geothermal Data Repository (GDR)

Geothermal Electricity Technology Evaluation Model (GETEM) Individual Case Files and Summary Spreadsheet (GETEM version Spring 2013).

Geothermal Technologies Program GETEM and LCOE Improvements Review (March 21, 2013).

Geothermal Power Cost Data

When you create a new case or file, SAM populates inputs with default values to help you get started with your analysis. So, if you create a case for a utility-scale geothermal project with a single owner, SAM populates the inputs on the Financing and System Costs pages with values that are reasonable for a typical geothermal project for power generation in the United States. The default values are just a starting point: As you develop and refine your analysis, you should change the inputs to values that are appropriate for your analysis scenario.

NREL Annual Technology Baseline (ATB)

Robins, J.; Kolker, A.; Flores-Espino, F.; Pettit, W.; Schmidt, B.; Beckers. K.; Pauling, H.; Anderson, B. (2021). 2021 U.S. Geothermal Power Production and District Heating Market Report. National Renewable Energy Laboratory. NREL/TP-5700-78291. (PDF 10 MB)

Cross, J.; Freeman, J. (2009). 2008 Geothermal Technologies Market Report. 46 pp.; DOE/GO 102009 2864 (PDF 1.3 MB)

Geothermal Electricity Technology Evaluation Model. U.S. Department of Energy Geothermal Technologies Program.