Power · Enhanced geothermal
Rung two · years
Enhanced geothermal
The heat is already under the site. The only question is how far down, and how long the drilling takes.
Conventional geothermal needs a rare natural coincidence — heat, water and permeable rock in the same place — which is why it exists in a handful of countries. Enhanced geothermal supplies the parts nature left out: wells are drilled into hot dry rock and the path between them is engineered. What comes back is continuous, renewable and indifferent to the weather, on a surface footprint measured in acres.
- Bridge
- Geothermal
- SMR
It is continuous, renewable and small on the surface, so it is what the bridge hands the load to. It cannot go first, because a site that waits for a well never opens. Why this order
Power · Geothermal → How it works
Two wells and the rock between them
A closed loop through hot rock.
Water goes down one well, moves through fractured rock that heats it, and comes back up the other. Nothing is burnt, nothing is delivered, and the same loop runs through the night and through the winter.
01Injection well
Water is pumped down one well. It is the same drilling equipment, the same crews and the same supply chain the oil and gas industry already runs.
02The reservoir
Between the wells, the hot rock is fractured so water can move through it. “Enhanced” means exactly this: the heat was always there, and the permeability is what gets engineered.
03Production well
What comes back up is hot enough to raise steam. Nothing was burnt to heat it, and nothing had to be delivered.
04Surface plant
A turbine, a generator and a cooling stage, sitting on a footprint measured in acres rather than square miles. The water is returned to the injection well and goes round again.
Power · Geothermal → Depth
Temperature against depth
Everywhere is hot enough. The question is how far down.
Rock warms with depth at a rate that varies by geology and barely changes with the seasons. Set that rate and the working temperature you want, and the drilling programme falls out of the arithmetic.
- Depth to that temperature
- 6.2 km
- Against ordinary deep-well reach
- Drillable
The gradient is yours to set because a real one is measured at a real site, and there is no Xalant site to measure. Slide it down toward ordinary crust and watch the depth run away from the drill — that gap is the entire engineering problem the word “enhanced” is pointing at.
Power · Geothermal → Why years
The rung that cannot be hurried
Why this one takes years, and why that is survivable.
Almost all of the work is underground, where nothing can be accelerated by ordering earlier.
A well is drilled, then logged to find out what is actually down there. The rock between the wells is stimulated so fluid can move through it. The flow path is tested, and the test tells you whether the next step is worth taking or whether the plan changes. Only once that sequence has produced a reliable loop is there something for a turbine to connect to. Each stage depends on what the previous one found, which is exactly why they cannot be run in parallel and why money does not compress them.
That is a devastating timeline for a site with nothing running, and an affordable one for a site already carrying its load on the bridge. This is the single most important thing on this page: enhanced geothermal is not slow because it is immature, it is slow because it is drilling — and the ladder is built the way it is so that the slowness costs time rather than revenue.
The field itself is no longer theoretical. Commercial enhanced-geothermal projects are under construction, and the drilling techniques they rely on were paid for and perfected by the oil and gas industry over the last two decades — which means the rigs, the crews and the tooling exist today rather than needing to be invented. Named projects, their capacities and their dates are stated on this site only with the operator’s own source and the date it was read, so they will appear here when those are attached and not before.
Power · Enhanced geothermal → FAQ
Asked before anyone asks
Questions worth answering honestly.
- Is this the same as the geothermal that runs off hot springs?
- No, and the difference is the whole point. Conventional geothermal needs a rare natural combination of heat, water and permeable rock, which is why it exists in a handful of places. Enhanced geothermal supplies the missing parts: the heat is already under almost everywhere, so wells are drilled into hot dry rock and the permeability is engineered by fracturing the rock between them. It turns a geography problem into a drilling problem.
- Why does it take years when a gen-set takes months?
- Because almost all of the work is underground and none of it can be rushed by ordering earlier. Wells are drilled and logged, the rock between them is stimulated, the flow path is tested and re-tested, and only then is there something for a surface plant to connect to. Each of those steps tells you whether the next one is worth doing, which is exactly why they cannot run in parallel.
- Does injecting water into rock cause earthquakes?
- Induced seismicity is a real and well-studied consequence of injecting fluid at depth, and pretending otherwise would be the wrong way to answer this. It is managed rather than wished away: with seismic monitoring in place before injection starts, with limits agreed in advance on how much shaking triggers a reduction or a stop, and with siting that keeps the stimulated volume away from known faults. A project that cannot commit to that monitoring is not a project we would build.
Power · Next step
Tell us the megawatts. We will draw the rungs.
Model the stack against your own assumptions, then send it as a capacity request with the inputs already filled in.