From how they work to what they cost, state-by-state incentives, and whether geothermal is right for your home — all in one place.
Learn How It Works → Comprehensive guides · Real data · Expert analysisIn-depth guides, real data, and expert analysis to help you make informed decisions about geothermal heating and cooling.
Understand geothermal heat pumps — the technology, installation process, maintenance, and how they heat and cool your home using the earth's energy.
Find incentives, rebates, tax credits, and installer information specific to your state. Comprehensive guides for all 50 states.
See how geothermal stacks up against traditional HVAC, solar, and other systems. Real cost breakdowns and ROI timelines.
Stay current with geothermal legislation, technology breakthroughs, major projects, and market trends shaping the industry.
Resources for HVAC contractors, installers, and builders — certification guides, business opportunities, and best practices.
Estimate your savings, find incentives in your area, and access resources to plan your geothermal project.
Geothermal heat pumps use the earth's constant underground temperature to heat and cool your home — dramatically reducing energy costs and environmental impact.
Geothermal systems use 25–50% less electricity than conventional heating and cooling, saving homeowners $1,000–$2,500 annually.
No combustion, no emissions on-site. Geothermal moves heat rather than creates it, using the earth's constant underground temperature.
Indoor components last 25+ years. Ground loops last 50+ years. That's 2–3x longer than conventional HVAC with lower maintenance.
Expert analysis and practical guides — updated regularly.
Salton Sea lithium with sourced numbers: 198 ppm brine, LBNL's 4.1 million tonne LCE estimate, the demonstration plant that failed, and the battery-grade carbonate made in June 2026.
Read More →The Geysers in Northern California is the world's largest geothermal field — and it has no geysers. The history, the 1987 peak, the wastewater that revived it, and how to visit.
Read More →Two very different systems get called geothermal driveway heating. ASHRAE design numbers, a DOE-documented heat pump deicing system, and an honest verdict.
Read More →Geothermal Insider is an independent research and publishing project. We don't design systems, sell installations, or take referral fees from contractors — so the only thing we're optimizing for is whether a guide actually helps you make the decision.
Every guide is built from primary sources — federal guidance, state energy office programs, utility documents, and manufacturer specifications. Where a number is uncertain or varies by location, we say so instead of guessing.
How We Research →Claims are sourced to DOE and EPA guidance, state incentive databases, utility program pages, and manufacturer specifications — and linked so you can check them yourself.
Launched March 9, 2026 and growing since — new guides, state incentive changes, and a daily-checked industry news feed, every item linked to its source.
Start with the basics — learn how geothermal heat pumps work and whether they're a good fit for your home or building.
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