Geothermal energy pulls heat from deep underground to generate electricity and warm buildings, and it does so around the clock with minimal carbon emissions. While solar and wind get most of the attention in clean energy conversations, geothermal offers something neither can: a steady, always-on power source that doesn’t depend on weather, imported fuel, or massive land areas. Here’s why it deserves a bigger role in the energy mix.
It Runs Around the Clock
The single biggest advantage geothermal has over other renewables is reliability. The Earth’s interior produces heat continuously, so geothermal plants don’t shut down when the sun sets or the wind stops. According to the International Energy Agency, global geothermal capacity had a utilization rate above 75% in 2023. Wind power came in under 30%, and solar PV under 15%. That means a geothermal plant produces electricity at or near its maximum capacity for roughly three-quarters of the year, while a solar installation sits idle most of the time.
This matters for the electrical grid. As more intermittent sources like wind and solar come online, grid operators need “baseload” sources that keep power flowing reliably. Geothermal fills that role without requiring batteries or backup gas turbines, which adds cost and complexity. It can also store excess electricity as heat underground for later use, helping balance supply and demand across the grid.
Very Low Carbon Emissions
Geothermal is one of the lowest-carbon electricity sources available. A systematic review by the National Renewable Energy Laboratory found median lifecycle emissions of just 11.3 grams of CO2 equivalent per kilowatt-hour for the cleanest type of geothermal plant (hot binary systems). Even the higher-emitting geothermal designs came in at 32 to 47 grams. For comparison, coal plants typically emit around 800 to 1,000 grams per kilowatt-hour, and natural gas around 400 to 500. Geothermal produces roughly 95% less carbon than fossil fuels per unit of electricity.
Those emissions that do exist come mostly from small amounts of dissolved gases released from underground reservoirs and from the energy used to build the plant and drill wells. There’s no combustion involved, no fuel to transport, and no ash or particulate pollution to manage.
Protection From Volatile Energy Prices
Fossil fuel prices swing dramatically based on geopolitics, supply disruptions, and speculation. Geothermal sidesteps all of that because its “fuel” is the Earth’s own heat, which is free and inexhaustible on human timescales. Once a plant is built, operating costs stay predictable for decades.
This price stability shows up in real contracts. Recent power purchase agreements for geothermal projects in the United States range from about $68 to $75 per megawatt-hour, locked in for 20 to 30 years. A project in Nevada secured pricing at $67.50 per megawatt-hour for 25 years, while facilities in California and Hawaii signed deals between $68 and $75. These long-term fixed prices are possible precisely because there’s no fuel cost to fluctuate. Researchers at the University of Leeds have pointed out that even countries with extensive wind and solar still see consumer prices spike when a small fraction of electricity comes from expensive natural gas. Geothermal helps break that link between gas markets and electricity bills.
A Small Physical Footprint
Geothermal plants take up far less space than wind farms or solar arrays for the same amount of power. The U.S. Department of Energy notes that geothermal facilities have a lower profile and smaller land footprint compared to many other generation technologies. A typical geothermal plant looks like a modest industrial building. It doesn’t need fuel storage yards, coal piles, cooling ponds, or the vast acreage that solar and wind require. This makes geothermal practical in areas where land is scarce or expensive, and it minimizes habitat disruption.
Steady Local Jobs
Building a geothermal plant creates a significant number of jobs, and, unlike construction-heavy projects that wind down after installation, geothermal facilities need permanent staff for decades. Department of Energy data on a typical 50-megawatt geothermal plant shows about 690 person-years of employment during construction, split between well drilling and power plant building. Once operational, around 71 permanent jobs per year are needed to keep the system running, with roughly 39 of those based at the plant site.
That ongoing local employment is notable. Solar and wind farms require relatively little maintenance staff once built. Geothermal’s wells and fluid systems need continuous monitoring, maintenance, and occasional re-drilling, which sustains skilled jobs in often rural communities for the 30- to 50-year life of a plant.
New Technology Is Expanding Where It Works
Traditional geothermal energy has been limited to regions with obvious volcanic or hydrothermal activity: Iceland, parts of California, the Pacific Ring of Fire. That’s changing fast. Enhanced geothermal systems, or EGS, create artificial reservoirs by injecting water into hot, dry rock deep underground. This technique can potentially unlock geothermal energy almost anywhere, because temperatures rise with depth regardless of surface geology.
In February 2024, the U.S. Department of Energy announced its first round of EGS pilot demonstrations. Fervo Energy is building a project in Utah aiming to produce at least 8 megawatts from each of three wells at a site with no existing geothermal production. Mazama Energy is testing “super-hot” EGS at temperatures above 375°C near Oregon’s Newberry Volcano. A fourth funding round specifically targets the eastern United States, where no conventional geothermal resources exist but deep rock temperatures are still high enough to generate power.
If these pilots succeed at commercial scale, the geographic limitations that have kept geothermal a niche player effectively disappear. The DOE’s GeoVision analysis has suggested that EGS could increase U.S. geothermal capacity many times over, turning it from a regional resource into a nationwide one.
Heating and Cooling, Not Just Electricity
Geothermal energy isn’t limited to power plants. Ground-source heat pumps use the stable temperature a few meters underground to heat buildings in winter and cool them in summer. These systems work everywhere, not just in geothermally active regions, because the shallow ground stays around 10 to 15°C year-round in most climates.
On a larger scale, district heating systems can pipe hot water from deeper geothermal wells to warm entire neighborhoods. The University of Leeds, for example, uses groundwater beneath its campus to provide renewable heat, significantly reducing its natural gas consumption. Cities in Iceland, France, and China already heat large portions of their buildings this way. This “direct use” of geothermal heat is often more efficient than converting it to electricity first, and it displaces the gas boilers and furnaces responsible for a large share of building emissions.
How It Compares Overall
- Versus solar and wind: Geothermal provides baseload power with a 75%+ utilization rate, compared to under 30% for wind and under 15% for solar. It doesn’t need battery storage or backup generation to keep the grid stable.
- Versus natural gas: Geothermal emits roughly 90 to 97% less carbon per kilowatt-hour, requires no fuel imports, and locks in stable pricing for decades instead of riding volatile commodity markets.
- Versus nuclear: Geothermal plants are faster and cheaper to build, carry no risk of meltdown or radioactive waste, and can be scaled from small community systems to large utility plants.
The main drawback has historically been geography. You needed to be near a tectonic hotspot. With enhanced geothermal systems advancing toward commercial viability, that constraint is shrinking. The upfront drilling costs are high, but once a well is producing, the energy is essentially free for decades, with minimal fuel, waste, or maintenance costs compared to fossil fuel alternatives.