Geothermal Energy

Geothermal energy harnesses heat from the Earth's interior to generate electricity and provide direct heating. The Earth's core reaches temperatures of about 5,200°C (9,392°F), and this heat continuously flows outward. Traditional geothermal plants tap into naturally occurring hydrothermal reservoirs—areas where hot water and steam are trapped beneath the surface.

The technology has been used for over a century, with the first geothermal power plant built in Larderello, Italy in 1904. Today, geothermal provides reliable baseload power in over 30 countries, with the United States, Indonesia, Philippines, Turkey, and New Zealand leading in installed capacity.

Global geothermal capacity has grown to approximately 16 GW as of 2025, with projections suggesting it could reach 35 GW by 2030. The industry has attracted significant investment, with over $4 billion flowing into geothermal projects in 2024 alone. This growth is driven by improved drilling technologies, enhanced geothermal systems (EGS), and increasing demand for clean baseload power.

The United States remains the world leader with about 3.8 GW of installed capacity, primarily in California and Nevada. Indonesia has emerged as a major player with 2.4 GW, while Iceland generates nearly 30% of its electricity from geothermal sources. Kenya has become an African success story, with geothermal providing over 45% of its electricity.

Enhanced Geothermal Systems (EGS) represent the most significant advancement in geothermal technology. Unlike conventional geothermal that requires natural hydrothermal reservoirs, EGS creates artificial reservoirs by injecting water into hot dry rock formations. This technology dramatically expands where geothermal can be deployed—potentially anywhere on Earth where you can drill deep enough.

In 2024, Fervo Energy achieved a major milestone by successfully operating a commercial EGS plant in Nevada, partnering with Google to power data centers. The company demonstrated that EGS can be cost-competitive with other renewables, achieving costs below $50 per megawatt-hour. This breakthrough has sparked a wave of investment in next-generation geothermal projects.

Closed-loop systems represent another innovation, circulating fluid through sealed underground pipes without direct contact with rock formations. This approach eliminates concerns about induced seismicity and water contamination that have occasionally affected traditional geothermal operations.

Geothermal energy offers compelling environmental advantages. A geothermal plant produces on average 38 grams of CO2 per kilowatt-hour—about 5% of what a natural gas plant emits. Binary cycle plants, which use a secondary fluid to generate power, can achieve near-zero emissions.

The land footprint of geothermal is remarkably small. A geothermal facility uses about 1-8 acres per megawatt, compared to 5-10 acres for solar and 30-60 acres for wind. This makes geothermal particularly attractive for regions with limited available land. Additionally, geothermal plants operate 24/7 with capacity factors exceeding 90%, compared to 25-35% for solar and wind.

The emerging frontier of geothermal is superhot rock (SHR) technology, which targets rock formations at temperatures above 375°C. At these temperatures, water becomes supercritical—a state between liquid and gas—capable of carrying 5-10 times more energy than conventional geothermal fluids. A single superhot well could produce 50 MW or more, compared to 5-10 MW from conventional wells.

Projects in Iceland, Japan, and the United States are pioneering this technology. The Iceland Deep Drilling Project reached temperatures of 427°C in 2017, demonstrating the potential. If superhot rock geothermal can be commercialized, experts estimate it could provide virtually unlimited clean energy—enough to power human civilization many times over.

Geothermal energy is poised for exponential growth. The U.S. Department of Energy's "Enhanced Geothermal Shot" initiative aims to reduce EGS costs by 90% by 2035, which would make geothermal one of the cheapest forms of energy available. Major tech companies including Google, Microsoft, and Meta are investing in geothermal to meet their 24/7 clean energy commitments.

With advancements in drilling technology borrowed from the oil and gas industry, along with AI-driven exploration techniques, the geothermal industry is solving the technical challenges that have historically limited its growth. As the world seeks reliable, clean baseload power to complement variable renewables like solar and wind, geothermal is finally getting its moment in the sun—or rather, from the heat beneath our feet.