Geothermal energy has always carried an odd reputation in the clean energy conversation: universally acknowledged as reliable, constant, and low-carbon, yet historically confined to a small number of geologically fortunate places, Iceland, parts of Indonesia, sections of the western United States, where volcanic or tectonic activity brings usable heat close enough to the surface to extract economically. That geographic confinement has been the central limitation on geothermal’s contribution to the global energy mix for as long as the technology has existed. A wave of deep-drilling advances now under active development promises to remove that constraint largely, extracting geothermal heat from standard hot dry rock formations that exist, at sufficient depth, essentially everywhere on the planet’s crust.
The technology driving this shift is generally referred to as enhanced or engineered geothermal systems, and the core engineering insight is straightforward even if the execution is not: rather than relying on naturally occurring hydrothermal reservoirs, where hot water or steam is already present near the surface, engineered systems drill deep enough to reach hot rock, then create or exploit fracture networks within that rock and circulate fluid through it to bring heat to the surface. Drill deep enough, essentially anywhere, and the rock is hot; the temperature gradient of the earth increases with depth almost everywhere on the planet. The historical barrier was never the presence of heat, which is nearly universal at sufficient depth, but the cost and difficulty of drilling deep enough, often three to five kilometers or more, to reach commercially useful temperatures economically.
Progress on that drilling barrier has come substantially from techniques borrowed and adapted from the oil and gas industry, particularly directional drilling and hydraulic fracturing methods refined over decades of shale extraction. Several companies developing engineered geothermal systems have demonstrated the ability to drill deeper, faster, and at lower cost than traditional geothermal drilling methods, in some documented pilot projects cutting drilling time by a substantial margin compared to conventional approaches. Millimeter-wave and plasma drilling technologies, still earlier-stage but under active development by multiple ventures, aim to bypass mechanical drill-bit wear entirely by vaporizing rock rather than grinding through it, which if proven commercially viable could reduce deep-drilling costs further still.
The commercial case for engineered geothermal has strengthened enough that it is attracting capital well beyond the specialist clean-energy investment community that funded early pilot projects. Several major technology companies, driven substantially by the enormous and constant electricity demand of data centers and AI computing infrastructure, have signed long-term power purchase agreements with engineered geothermal developers, betting on geothermal’s key advantage over solar and wind: it is available continuously, regardless of weather or time of day, which makes it structurally better suited to the round-the-clock power demand of computing infrastructure than intermittent renewables paired with storage, at least until battery storage costs fall considerably further.
None of this means unlimited geothermal energy anywhere on Earth is imminent in a practical, deployed sense, and claims suggesting otherwise deserve real skepticism. Commercial-scale engineered geothermal projects currently operating or under construction remain concentrated in a handful of pilot sites, predominantly in the United States, with drilling costs still high enough that engineered geothermal is not yet cost-competitive with solar or wind on a pure levelized-cost-of-energy basis in most markets, even as it offers advantages those technologies cannot match on reliability. Induced seismicity, small earthquakes triggered by fracturing rock deep underground, remains a live technical and public-acceptance concern that has already complicated or halted specific geothermal projects, and scaling engineered geothermal to meaningful global capacity will require managing that risk far more systematically than current pilot-scale projects have needed to.
The realistic trajectory, based on current cost curves and the pace of drilling technology improvement, points toward engineered geothermal becoming commercially competitive in an expanding set of markets over the next five to ten years, rather than becoming universally deployable overnight. Regions with favorable subsurface geology even short of true volcanic activity, much of the western United States, parts of India’s Deccan Plateau, and sections of continental Europe, are likely to see commercial projects well before engineered geothermal becomes viable literally anywhere, which remains a longer-term proposition dependent on drilling costs falling substantially further than current technology has demonstrated.
What has genuinely changed, and what justifies the current wave of investment and attention, is that geothermal’s fundamental constraint has shifted from a geological one, needing to be in the right place, to an engineering and cost one, needing to drill deep enough affordably, and engineering and cost constraints are the kind that sustained investment and technological iteration can plausibly solve over a decade rather than being permanently fixed by geography. That is a genuinely different, and more optimistic, starting point than geothermal energy has had at any prior point in its history, even if ‘unlimited clean energy from bedrock’ remains, for now, a description of the technology’s ceiling rather than its current, still fairly limited, deployment.
For India specifically, the implications are worth noting even at this early stage of the technology’s global maturation. Parts of the Deccan Plateau and other regions with elevated, though not volcanic, subsurface temperatures could become viable engineered geothermal sites as drilling costs fall over the coming decade, offering a genuinely reliable, always-available complement to India’s rapidly expanding but weather-dependent solar and wind capacity. Realizing that potential would require the kind of sustained public and private drilling-technology investment that has so far been concentrated overwhelmingly in the United States, alongside a regulatory framework for managing induced-seismicity risk that India, like most countries, has not yet had reason to build.
– Sivarama Murthy Yellamraju
