This month we talk about Fervo, fracking, and EGS.
We also discuss consistent clean energy production, hot springs, and oil majors.
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Transcript
Since the beginning of human civilization—as far back as the Stone Age, and probably before that, too—humans have been using natural hot springs for bathing, the heating of homes, for washing things, and for powering various sorts of basic machines and processes, including those that allowed for the extraction of boric acid, which was used for cleaning and food-preservation purposes, from volcanic mud in Italy back in 1827.
Geothermal heating systems popped up in Idaho and Oregon in 1892 and 1900, respectively, and in 1904, the first geothermal power generator was tested in Italy, producing enough electricity to power four lightbulbs. That test led to the production of a commercial-scale power station in the same region, and the success of that station led to experimental versions of the same in Japan and California, in the 1920s.
Greenhouses heated by geothermal wells popped up in Idaho, Iceland, and Tuscany in the mid- to late-1920s, and various means of capturing dissipated heat from boreholes, digging deep into the ground and then aggregating the heat found down there into a usable temperature, and then pulling that heat upward, were developed soon after, allowing for the broader-scale heating of homes and even entire towns in the 1930s and 1940s, in geothermically active areas.
Although geothermal heat was used directly for all sorts of purposes during this time, though, the production of electricity from such activity remained the domain of Italy until 1958, when New Zealand started using flash steam technology to generate steam from all that heat, using that steam to spin turbines.
Similar technologies were used to produce electricity in California in 1960, and from that point forward we started to see all sorts of interesting applications of known geothermal sources for the production of electricity, that enthusiasm amplified during the 1970s, when a global energy crisis incentivized exploration into non-fossil fuel energy sources.
Until recently, however, the use of geothermal energy has been limited to areas in which the local tectonic situation allows geothermal activity—underground heating activity, basically—to bubble up close to the surface, and in which the right supplementary conditions, like the presence of liquid and porous rock, allowed us to tap that accessible heat for our own, intentional use.
So places with hot springs and geysers have been generally favorable for this sort of energy-generation for a long time, but it hasn't been feasible anywhere else.
What I'd like to talk about today is how new technologies and methods might allow for the expansion of geothermal across a far larger portion of the planet.
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A US-based startup called Fervo Energy recently announced a breakthrough in its efforts to develop a scalable, enhanced geothermal system.
Geothermal energy is desirable because it's fossil fuel-free, while also being stable and consistent: unlike solar or wind, it doesn't produce electricity intermittently, while the sun is shining or wind is blowing, which means like a coal plant or nuclear plant, it produces a steady flow of electricity into the grid, and thus doesn't require backups like batteries, to capture excess for release during non-production periods.
Consequently, geothermal energy systems are pretty great as standalone efforts, but are also super-useful alongside solar and wind, as it can provide a baseline amount of energy 24/7, with those other sources producing more on top of that; it fills the gaps, basically, so even a relatively small amount of energy from geothermal tends to be welcome, in areas that are able to utilize it.
The relevant range for such technologies has been limited, though, because of the necessity to have tappable underground heat sources nearby; many cities have been built near historic underground heat sources because they're so useful and appealing, but most cities do not have one close enough to use in this way, which has made this a niche energy source up till this point.
Enhanced geothermal expands the potential range of such systems, artificially creating the circumstances necessary to tap underground heat sources.
In essence, naturally occurring, tappable geothermal systems—which are more formally called hydrothermal systems—contain heat, but also fluids and permeability, which in this context means porous rock formations that allow the contained fluids, bearing that heat, to move around; a natural convective energy system.
Enhanced geothermal systems, or EGS, in contrast, uses similar technologies to those used in hydraulic fracturing, often shorthanded as fracking, to bring about those same circumstances in more areas.
Fracking is a method of exploiting hard-to-utilize oil resources that involves pumping pressurized liquids into a bedrock formation, cracking it into pieces which then allows petroleum, brine, and natural gas to flow freely.
Fracking methods and technologies have been great for the North American oil industry, which has vast reserves of fossil fuels that can only be accessed in this relatively expensive and often quite environmentally destructive manner, and the idea is that these same technologies can be used, in a one-off fashion, rather than continuously, as is the case with oil and gas extraction—to add liquid into dry, hot underground formations, and to crack these formations in such a way that they become porous.
So a lot of the same dangers and negative consequences of fracking, but the procedure is done once, rather than over and over, to make some cracks and inject some liquid into a hot underground formation, which in turn makes it a useful formation for geothermal energy purposes.
So this technique makes areas that were previously nonviable for geothermal energy, viable, their underground formations artificially reshaped so that they're similar to those that naturally have those heat, liquid, porosity elements in place.
Researchers and industrialists have been attempting to make EGS work since the 1970s, but were never able to get the composition right, their tools never quite up to the task, the resulting underground landscape never becoming what they needed it to be for persistent geothermal energy use.
Fervo's breakthrough, then, is related to their application of these technologies in just the right way so that, after a bit of underground fracturing and liquid dissemination, the relevant area becomes suitable for geothermal, whereas previously it was not.
The big caveat here is that this breakthrough happened during a demonstration of their technology, and they're now in the process of replicating their one-time successful model in another state; the successful test was done in Nevada, and they'll do this next one in Utah, where their site is currently under construction.
To provide a sense of the size of their efforts, thus far, the demo site in Nevada was able to generate 3.5 megawatts of electricity during their 30-day test, which is enough to power about 2,625 homes—and they plan to connect that site to the grid, full-time, later in 2023, intending to use it to power Google's data centers and other Nevada-based infrastructure, as part of a prearranged deal with Google parent-company Alphabet which is investing in such technologies to help them decarbonize their operations.
The next-step, under-construction project in Utah is expected to produce about 400 megawatts of electricity, which would be enough to power about 300,000 homes—a huge step-up, but that's based on expectations set by their initial, far smaller Nevada site, so we'll see if they can replicated that initial success; however that turns out, though, they're already in the process of getting permits and appraisal work done for a half-dozen other sites across the country, as well.
If things go according to plan, that Utah site will be fully up and running by 2028, and that's part of why entities like Alphabet are investing in this type of non-fossil fuel-based power source, today: of many of these efforts won't pay off for a handful of years, at the earliest, and though there's still a fair bit of uncertainty surrounding them, geothermal is a time-tested energy resource, so the tapping and utilizing of this type of energy for all sorts of use-cases is a known-entity at this point, which makes it a safer-bet, by many metrics, than other persistent-energy-generating options, like small modular nuclear power plants, and even more currently pie-in-the-sky options, like fusion power; we know this works, the big uncertainty is whether they can consistently get the below-ground, natural-ish infrastructure reshaped consistently, which is what would allow those well-honed technologies to be installed and useful in more places.
This breakthrough is being considered a big win by many players in the clean energy space, but there are still concerns because of how it was accomplished.
We've long known that most areas have enough heat underground, in accessible areas, to make this sort of thing feasible at some point, if we could solve the liquid and porosity issues: if we could make that heat more accessible and transferable, basically.
Fracking technologies, though, have been associated with all kinds of incredibly damaging environmental issues, in some cases devastating local ecosystems, and even, in true super-villain form, causing artificial earthquakes that have damaged cities and terrified residents.
Geothermal is also plagued by cost-related issues, as this type of electricity-generation is expensive compared to other options: it's usually a fair bit cheaper than using coal, if we ignore government subsidies on fossil fuels, at least, and almost always cheaper than nuclear, as well, by a wide margin, but it's a lot more expensive than wind and solar, at times and in some areas costing twice as much or more than both of these increasingly inexpensive and widely distributed options.
This effort, it's hoped, will help bring down those costs, as more areas being available for this type of power generation means more economies of scale: making more of something tends to reduce its associate costs.
And the US government has said it's hoping to reduce the cost of geothermal energy infrastructure by as much as 90% over the next decade, which would make it an incredibly viable alternative to other stable, consistently producing clean energy production options, like nuclear and hydro, and not-clean holdover energy sources like natural gas.
One more interesting tidbit related to this development is that we're seeing more traditional energy companies—which in this case means fossil fuel companies—scooping up carbon-capture and storage assets, which could allow them to capture their own emissions at the source, but also, potentially, someday, become big players in the broader grabbing-CO2-from-thin-air industry that, it's hoped, maybe, will allow us to reduce the amount of CO2 we've pumped into the atmosphere, bringing us back to someplace closer to where we've been since the dawn of human civilization, climactically.
They're investing in such assets, in part, because they are in the best position to do so: their technologies, their infrastructure, like pipes and underground wells, are almost uniquely suited to serve this carbon-capture purpose, and it would be interesting, almost to the point of wild irony, if these energy companies ended up being pivotal players both in the capture and storage of CO2, but also in the production of a foundational zero-emissions energy source, like geothermal.
If Fervo's methods prove to be viable in different locations, beyond their successful demo, it may be that we see the Exxon's and Chevron's of the world stepping into this space, as well, utilizing their hard-won and heavily-invested-in technologies and drilling/fracking/underground operations know-how to produce ever-better geothermal wells, allowing them to get their hands in the energy of the future, and perhaps, at long last, providing them with enough clear economic incentive to finally pivot away from their current golden goose, all those extractable, fossil fuel-based energy assets to which they're still, currently at least, clinging.
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Show Notes
https://www1.eere.energy.gov/geothermal/pdfs/egs_basics.pdf
https://en.wikipedia.org/wiki/Fracking
https://en.wikipedia.org/wiki/Enhanced_geothermal_system
https://www.energymonitor.ai/news/high-upfront-costs-stunt-growth-of-geothermal-in-the-us/
https://archive.ph/0htYW
https://interestingengineering.com/innovation/commercial-scale-geothermal-energy-production
https://www.wired.com/story/a-vast-untapped-green-energy-source-is-hiding-beneath-your-feet/?mod=djemfoe
https://web.archive.org/web/20130622092009/http://www.ipenz.org.nz/heritage/itemdetail.cfm?itemid=84
https://en.wikipedia.org/wiki/Geothermal_power
https://en.wikipedia.org/wiki/Geothermal_energy
