By Irina Slav
With so much talk about offshore wind and utility-scale solar, it is easy to forget about one other abundant, emission-free energy source. Geothermal has garnered a lot less attention than the more established forms of renewable energy generation, but this is slowly changing as parts of the world increasingly focus on replacing fossil fuels with cleaner alternatives. Alberta, for example, will be promoting the development of geothermal energy as a means of diversifying its heavily oil-dependent economy. This week the province’s legislators introduced a bill seeking to promote the nascent industry by setting rules and guidelines and establishing the authority that will control land use for geothermal.
“Alberta is uniquely positioned to attract investment in this emerging industry because of its geothermal resources, leadership in drilling technology, and extensive oil and gas expertise.”
Geothermal resources are in fact abundant everywhere: the Earth’s core radiates heat outwards into the mantle and the crust. Oil and gas drillers are familiar with this heat and know that the deeper you drill, the hotter it gets. For oil and gas drilling, this could be a problem, so the industry has developed ways to solve it. For geothermal drilling, heat is the goal. The oil and gas industry is therefore in a really unique position to make the most of geothermal resources, not just in Canada.
The European Union is also interested in the heat that the insides of our planet generate. A project sponsored by Brussels, MEET, set out to tests the viability of geothermal extraction from oil wells. This is a lower-cost alternative to drilling new wells specifically for geothermal energy extraction, and costs are an issue with geothermal. The project has managed to generate electricity using the heat from oil well brine extracted from a well in France along with the crude. The result is potentially significant because the temperature of the brine was not all too high at 92 degrees Celsius. Yet it has yet to be replicated on a wider scale.
Temperature is important in geothermal. Drilling wells is an expensive undertaking and the deeper the well, the more expensive it becomes. Yet it is at greater depths that, according to geothermal energy experts such as Jamie Beard from the Geothermal Entrepreneurship Organization at the University of Texas at Austin, the real potential of geothermal energy shines.
We’re talking temperatures of more than 200 degrees Celsius here. That is some intense heat that, if harnessed, can join solar and wind—and possibly even eclipse them in some parts of the world—as a mainstream source of zero-emission energy. The fact that scientists have estimated geothermal could save us 1 billion tons of carbon dioxide a year should be additional motivation.
For all its promise, one naturally wonders why geothermal has not yet become a popular renewable energy solution, at least in some parts of the world (excluding Iceland where it is the main source of energy). The problem is capital costs. These are high, and it has been difficult for companies active in the field to convince investors of the commercial viability of their projects.
As David Roberts writes in a detailed overview of geothermal for Vox, geothermal drillers enjoyed a burst of support during Obama’s first term, but that started to dwindle as it didn’t produce immediate results and investors turned their attention elsewhere. The U.S. is today the country with the most installed geothermal generating capacity, but new additions are slow. Yet since the early 2000s, geothermal drillers have learned to use the technology that made the United States the world’s largest oil and gas producer: fracking. And fracking could do for geothermal what it did for oil and gas.