Assertion Supported AI assessment confidence: 95% certainty 4/5 debate potential 1/5

Horne: Binary geothermal plants release virtually zero atmospheric emissions

Dr. Roland Horne · Going deep on next-gen geothermal · Jun 27, 2024 · at 8:28

Dr. Roland Horne describes how binary geothermal power plants operate as closed-loop systems using heat exchangers.

0:00 / 0:14exact quote · 14.3s

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“Because the water never leaves, the geothermal water never leaves the heat exchanger, there's basically no emissions at all from the subsurface out into the atmosphere of the environment. The water stays in the pipe, goes back in the ground. It never sees the light of day.”

quote is from the automated transcript, cleaned for reading: filler sounds and stutters are removed, nothing is rephrased. names can be misheard (the analysis reads context, assessments check outside sources). how →

The claim, plainly

Binary geothermal power plants release virtually no subsurface emissions into the atmosphere because the geothermal fluid remains fully enclosed in a closed-loop system.

a quote alone can be ambiguous, so this restates it with the references and context of the conversation around it resolved. AI-written; the tape below the player is the source.

Assessment

Technical reports and documentation from the U.S. Department of Energy (DOE), the National Renewable Energy Laboratory (NREL), the Energy Information Administration (EIA), and Argonne National Laboratory (ANL) confirm the claim. Binary-cycle geothermal power plants operate as closed-loop systems in which the subsurface geothermal fluid transfers its heat to a secondary working fluid via a heat exchanger and is reinjected underground under pressure without being exposed to ambient air. Consequently, non-condensable subsurface gases are not vented to the atmosphere, resulting in virtually zero direct operational emissions from subsurface brine.

DOE Geothermal Technologies Office and OpenEI documentation state that binary-cycle geothermal power plants operate in a closed-loop cycle and emit virtually zero emissions from subsurface fluids.
NREL's 2017 life-cycle GHG review of geothermal systems confirmed that operational direct emissions from binary plant geothermal fluids are negligible due to their closed-loop process design.
U.S. EIA technical primers confirm that in binary systems the geothermal water remains enclosed and returned to the earth, producing no air emissions from the geofluid.

Checked against

[1] energy.gov [2] exergyint.com [3] openei.org [4] asme.org [5] openei.org [6] energy.gov [7] osti.gov [8] eia.gov

binary cycle geothermal power plant direct emissions closed loop NREL Department of Energy geothermal binary cycle closed loop zero emissions binary geothermal power plant emissions closed loop DOE NREL EPA EPA geothermal energy binary cycle power plant emissions closed loop

assessed as of 2026-09-02

This assessment is an AI reading of a public statement, made against the cited references with the confidence shown. It can be wrong. The quote, the tape and the references are all on this page; if something is off, use report an error below. full disclaimer →

Mentioned

binary turbine emissions geothermal power

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Assertion Partly supported

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Horne: Binary geothermal plants release virtually zero atmospheric emissions

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