Geothermal power - tapping the heat beneath our feet

In 2019, frustrated at seeing a key energy source go untapped, Beard moved to Texas and started the Geothermal Entrepreneurship Organization (GEO). The idea was to leverage oil and gas industry expertise to create a group of start-ups that would push forward next generation geothermal.

Building teams of veterans with 30-plus years of operational experience meant they could hit the ground running. “But it quickly became really obvious that they couldn't raise the money they needed to get into the field,” says Beard.

The vast majority of existing geothermal power generation uses naturally occurring hydrothermal sites. Perhaps the most famous example is Iceland, which lies over a volcanic hotspot.

Icelandic power plants need to drill only a couple of kilometres to extract hot water vapour. Sites where hydrothermal is evident and accessible, however, are very limited. Iceland is geographically unique. What Beard wants to drive forward is “geothermal anywhere” - projects that can map, identify and harvest heat at any location across the globe.

But GEO found that venture capital struggled to understand the complex mapping of subsurface characteristics necessary to identify a site. There was also a “huge cultural mismatch” between well-suited industry teams from Texas and hoodie-clad venture investors.

Private equity thought the idea sounded great, but wanted to see a first successful plant and then perhaps fund the second. GEO did help give rise to a new generation of Texas-based geothermal start-ups, several of which got funding. But Beard says venture capital funding tends to prefer the “sexiest, most moonshotty” version of geothermal. “I'm not trying to fund the moonshots,” she says. “I'm trying to fund the teams to go build a power plant right now.”

In a world where pictures of digital apes as non-fungible tokens (NFTs) have generated billions, there seems little reason why it should be so hard to raise a couple of hundred million for a transformative clean energy source.

“I would like to shout from the mountain tops that there is no reason,” says Beard. “So let's fix it.”

To this end, Beard has founded the non-profit Project InnerSpace, which has already secured philanthropic capital in the single-digit millions. The initiative has two main aims. Firstly, to create and provide a free-of-charge global database of subsurface characteristics – essentially, prospecting maps.

“Start-ups don't have the ability to go and spend a couple of hundred thousands dollars on site exploration before they do a project, so this is a problem across the board,” says Beard.

The maps will focus on areas within 100 kilometres of 100 major population centres across the globe. Sites in developing countries suffering from energy poverty could have particular potential. Likewise, those with existing coal power infrastructure that could be repurposed for geothermal. Much of the underlying data will come from the oil and gas industry, but needs to be collated, cleaned and combined with cutting-edge AI-based algorithms.

The second problem is the funding question. Here Beard is working to bring together a consortium of large energy consumers in a buyers alliance.

Natural candidates for such a consortium include major tech firms, which have energy-intensive data centres and a set of very ambitious decarbonisation targets. Beard has identified five major companies and hopes to build first-of-a-kind geothermal microgrids to both cool and power their data centres.

“We have one successful [example project] and every data centre in the world is going to want one, I think that's how we might lift off in the near term,” she says.

Globally, Beard expects to see an initial wave of “blind hydrothermal” projects, where subsurface mapping identifies hydrothermal resources that have no surface manifestations. Several such projects are under development.

Canadian firm DEEP Earth Energy Production is drilling 3.5km down into the Saskatchewan prairie to tap a geothermal aquifer. But there is a limited volume of blind hydrothermal locations. “Once we develop those sites that's pretty much it,” says Beard.

The focus then shifts to engineered geothermal systems (EGS) and advanced geothermal systems (AGS). Some EGS are technologically little different from hydrothermal, pumping water down into an open reservoir in hot rock and then bringing the heated water back to the surface.

Start-ups like US-headquartered Quaise are aiming to develop supercritical EGS - drilling down up to 20km to tap temperatures of 500° C and generate supercritical steam. Advanced approaches include closed-loop systems, which can use fluids other than water that go supercritical at lower temperatures.

“There's also data coming out of demonstrations now that are EGS-AGS hybrids,” says Beard. US-based Sage Geosystems has developed a pilot hybrid in South Texas, retrofitting abandoned wells and combining open-to-reservoir EGS and closed-loop geothermal technologies.

Different parts of the world boast very different subsurface conditions. The ideal situation would be to have a “buffet” of different technologies applicable to different conditions, says Beard.

But the most important thing now is for the industry to get on the learning curve. “That's how the shale boom happened,” she says. “You had teams going out and trying stuff and failing and trying to optimise and iterate - then all of a sudden, bam, the world’s rearranged.”