9 ms·
Geothermal Ahead of Schedule
- ChuckMcM 3y agoThis is a tweet thread from the CEO, the article is here (but paywalled) https://www.bloomberg.com/news/articles/2023-07-18/fervo-energy-says-it-has-achieved-geothermal-energy-tech-breakthrough https://www.bloomberg.com/news/articles/2023-07-18/fervo-ene... and what it shows is something that readers of this site should be very familiar with; technology advances impact adjacent markets "invisibly." My interest in PDC bits and the advancements in drilling related to how much simpler it would be to add fiber to the metro area by drilling horizontally 500' below street level (essentially no obstructions). The missing link there is lining the drill tube dynamically and going horizontally through water (for example) is not straight forward.
- jjulius 3y ago>... the article is here (but paywalled)... https://archive.is/0htYW https://archive.is/0htYW
- nocoiner 3y agoIs there a reason why you favor 500’ below ground level? My naive initial reaction is that seems like tremendous overkill in 99% of applications. Presumably in the vast majority of urban areas, 50’ would be more than enough to avoid any and all obstructions. I suppose once you decide to do something more than shallow trenching, then the marginal cost of additional vertical feet is fairly minor, but even in, say, NYC it seems like 500’ is way, way more buffer than you’d need in the worst case scenario (I have a vague recollection that the very deepest subway line is around 200’ underground, and that’s primarily due to a specific quirk of geography - a hill surrounded by two valleys).
- sidewndr46 3y agoHave you ever walked by a building under construction? It isn't uncommon to see foundation work going down >70 ft. The pilings themselves can be driven in even farther.
- nocoiner 3y agoWhat percentage of the average urban area is covered by buildings with 70’ foundations? I assume, perhaps incorrectly, that this is something that’s only required for skyscrapers or other similar large commercial buildings? And the average CBD is, probably, what, a low single digit percentage point of the corresponding urban area? I could certainly be wrong in my assumptions (hence my question!). But it still seems to me like it would be way more efficient to drill much shallower conduits in (what I assume is) the 99.999% of geography not covered by skyscrapers (and to either go deep or continue to go targeted in the remaining fraction).
- sambeau 3y agoI once sat and watched piles being driven for a small housing block, 4 stories high. These ones in fact: https://www.google.com/maps/@56.4618615,-2.9545922,3a,75y,26.85h,91.14t/data=!3m6!1e1!3m4!1sN_TqTjjAPLdiU6Bv4dfD5A!2e0!7i16384!8i8192?entry=ttu https://www.google.com/maps/@56.4618615,-2.9545922,3a,75y,26... Each pile was as about as high as the building. They pushed one in first and it went in like it was going through butter — literally seconds. They then stuck a second one directly on top which went in relatively easily. They then spent a thumping eternity putting a third one in on top of the other two. They repeated this process for days. So, that little building is resting on piles around 2-3 times its height.
- jrk 3y agoThat's a wonderfully evocative image, and I am a total non-expert so this sort of depth may be common, but I do note that that map pin is in what looks like harbor landfill. It may require an unusually deep foundation to reach bedrock there.
- nocoiner 3y agoFascinating, thanks. Do you happen to know what material they used for the piles? I’ve always assumed some kind of concrete column, but that seems possibly incompatible with the process you saw.
- voxelghost 3y agoYes, now I don't know which metro-area OP was talking about but in NYC bedrock varies between a few feet to about 150 feet below the surface. http://www.classichistory.net/archives/nyc-bedrock http://www.classichistory.net/archives/nyc-bedrock (see graph. note; unit is meter)
- WarOnPrivacy 3y ago> Is there a reason why you favor 500’ below ground level? Florida aquifer drills are >400' to reach 65° (year round) water. Temps get really static at that level.
- ChuckMcM 3y agoThree reasons, temperature stability, propensity to have rock vs sediment, and in the bay area, somewhat better earthquake resistance. When I was doing ops at Blekko we had a dark fiber run between our office and the data center to get our own "high speed" connection and part of that was a geo-technical survey. Of much of the SF Bay Area peninsula. The geologist suggested if we wanted to be subterranean and avoid both infrastructure and superfund sites, that we'd have to go down 500'. He expressed doubt that anyone would do that given the expense. And there are still some parts of the Santa Clara aquifer you can hit if you don't aim well.
- nocoiner 3y agoSuper interesting, thanks for the response!
- jxf 3y ago> Presumably in the vast majority of urban areas, 50’ would be more than enough to avoid any and all obstructions. This would definitely not be enough in, say, NYC. Grand Central Station is 150 feet below street level, for example. The Oculus is about 80 feet below street level. Things are deeper than they might first appear!
- eru 3y agoCould you just add the fibre to where you already have water pipes or sewers or underground electricity lines?
- aaron695 3y ago[dead]
- jjk166 3y agoHow would anyone connect to, nonetheless perform maintenance on, fiber 500' underground?
- jbm 3y agoI remember a lot of pushback in Japan about geothermal power and the impact it would have on hot springs in general. I wonder if this drilling method would affect their concerns?
- euniceee3 3y agoI am concerned about this as well. A number of geothermal projects in Nevada have reduced the flow of surrounding hot springs. It sounds like they are doing injection, which is similar to what Bottle Rock is doing in the Calistoga mountains. The real benefit I am hoping for is being able to revitalize the hot springs industry with soaking opportunities becoming more prevalent where they were not previously viable.
- hiddencost 3y agoStill need to prove scaling. " On the costs front, in 2022, Energy Secretary Jennifer Granholm announced the Enhanced Geothermal Shot, a target to reduce the cost of EGS by 90% to $45 per megawatt hour by 2035. Fervo’s costs for the Nevada project are “significantly higher” than that target, Latimer said, in part because it’s a first-of-a-kind project, but he said he expects next year’s EGS cost forecast to “decline rapidly.” "
- jandrese 3y agoExciting, but I always take pronouncements like this from new startups with a huge grain of salt.
- morning_gelato 3y agoHere is a white paper released by Fervo that describes what they've done in more detail: https://eartharxiv.org/repository/view/5704/ https://eartharxiv.org/repository/view/5704/
- JumpCrisscross 3y ago"The project involved drilling a first-of-a-kind EGS horizontal doublet well system, consisting of an injection and production well pair within a high-temperature, hard rock geothermal formation... During production testing, the system achieved flow rates of up to 63 L/s, production temperatures of up to 336 ◦F and a peak power production of 3.5 MW electric power equivalent." The team believes they can increase "the power capacity up to 8 MW of electric power per production well" and unlock economies of scale "because multiple wells can be drilled from a single pad location," which gains from "minimizing in-field rig moves, reducing drilling risk by drilling closely spaced vertical well sections, co-locating surface facilities infrastructure, and minimizing pipeline costs." Notably, "the rate and pressure responses between Injection Well 34A-22 and Production Well 34-22 were strongly correlated, with changes in one well causing a rapid response in the offset well typically on the order of minutes to tens of minutes." That means dispatchable generation.
- johntb86 3y agoAs a point of comparison, the average US oil well produces around 26 barrels a day, or 1.8MW.
- whatshisface 3y agoI don't have any megawatt convertible statistics handy, but the distribution is HEAVILY skewed. Take this as a rough indication: >An average marginal oil well in the United States produces about 2 barrels/day. Approximately 80 percent of all American oil wells are marginal wells, but they provide about 10-20 percent of American oil production. Approximately two-thirds of all American natural gas wells are marginal wells, averaging about 22 mcfd and providing 12 percent of American natural gas production https://www.ipaa.org/wp-content/uploads/2017/07/IPAACommentsSenateFinanceCommitteeTaxReformIssues.pdf https://www.ipaa.org/wp-content/uploads/2017/07/IPAAComments...
- 38 3y agosince Twitter is a piece of shit (only shows first tweet of a thread unless you're logged in), here you go: https://nitter.net/TimMLatimer/status/1681304496234991620 https://nitter.net/TimMLatimer/status/1681304496234991620
- dilDDoS 3y agoCan also try: https://farside.link/https://twitter.com/TimMLatimer/status/1681304496234991620 https://farside.link/https://twitter.com/TimMLatimer/status/... to use a random (functional) Nitter instance. Helps spread traffic around a little more evenly.
- jkrubin 3y agoThe geophysicist mentioned (JackNorbeck) is my cousin-in-law. He’s a smart dude.
- ksec 3y agoAs far as I can tell this is not a closed loop system. So how do we prevent Earthquake problems that happened in South Korea?
- JumpCrisscross 3y ago> this is not a closed loop system It's closer to closed than open. "The produced fluid was pumped through a series of holding tanks to provide the residence time for the water to cool sufficiently and was ultimately recirculated for injection" [1]. They did add "saline brine sourced from a nearby groundwater well," but presumably the system stabilizes at some point. [1] https://eartharxiv.org/repository/view/5704/ https://eartharxiv.org/repository/view/5704/
- deleted 3y ago[deleted]
- tony_cannistra 3y agoFrom the Bloomberg article: In many regions, the existing rock is hot enough but there isn’t enough permeability for fluid to flow through the hot rock. Through wells drilled deep underground, EGS injects fluid to create fractures, causing the permeability needed for electricity generation. My gut says they're using the same methodologies as hydraulic fracturing for oil and gas extraction for this, but I'm not sure. That raises a whole host of environmental concerns, particularly with regard to the high volume use of fresh water in places where it is scarce, and the impact of toxic high-pressure fracturing fluid on aquifers. Both are issues that have plagued communities where oil and gas fracturing takes place.
- JumpCrisscross 3y ago> gut says they're using the same methodologies as hydraulic fracturing for oil and gas extraction for this, but I'm not sure This is correct. > the high volume use of fresh water in places where it is scarce, and the impact of toxic high-pressure fracturing fluid on aquifers Petrochemical fracking constantly creates new fractures to unlock new seams; extracted resources don't replenish. Geothermal energy is different. You can stimulate once, then circulate and recapture; the heat one extracts renews itself. ("The produced fluid was pumped through a series of holding tanks to provide the residence time for the water to cool sufficiently and was ultimately recirculated for injection," though it was supplemented with "saline brine sourced from a nearby groundwater well.") Fundamentally, it has the capacity to be almost endlessly cleaner than its oil and gas counterpart. [1] https://eartharxiv.org/repository/view/5704/ https://eartharxiv.org/repository/view/5704/
- tony_cannistra 3y agoThanks. In principle I am wholeheartedly in support for geothermal as a renewable energy source, especially compared to fossil fuels. I think these kinds of developments to expand the potential for geothermal resources are super important. I guess I just would like to understand some of the externalities to this particular methodology. Especially since many of the parallels to oil and gas fracking are present, and the environmental track record there is poor.
- bilsbie 3y agoMods, Any idea why my submission yesterday didn’t supersede this one? It’s the exact same URL. https://news.ycombinator.com/item?id=36774063 https://news.ycombinator.com/item?id=36774063
- coffeeshopgoth 3y agoInteresting. In that part of the world, the crust is actually some of the thinnest on Earth. Shell drilled some thermal wells up there in the 70s - when it comes to tech, they have always been the most progressive of the E&P industry - that isn't saying much, but they have been more advanced/interested than any other. Because of the crust being thinnest there, the geothermal gradient is supposed to be better, but that being said, the original Shell wells weren't drilled deep enough - I reviewed them a long time ago, but think they were targeting some 300 feet. When done, all they did was make uncomfortably hot water and no steam - so they will probably need to go to that 500' mark someone here mentioned.
- XorNot 3y agoThe oil companies rebranded themselves as energy companies because they're definitely not stupid: if they can take their existing capability and use that to enter a whole new area, they'll do it. In particular because there's no actual competition between geothermal power and the petrochemical industry: oil is far and away a transportation fuel (and a bunch of other vital things), whereas stationary power is coal-generation. If they can take drilling expertise and turn it into a geothermal power concern cost efficiently, then they'll do that.
- pfdietz 3y agoIn the US, stationary power is more natural gas than it is coal. The ratio is nearly 2:1.
- jacknews 3y agoThis is great, but I think still limited areas with shallow hot rocks, and the temperatures are quite still quite low. so inefficient. The real prize is deep geothermal (20km+), giving 500C+ temps. That can operate almost anywhere, and be much more efficient to run.
- XorNot 3y agoIt is endlessly frustrating to me that we're not just ploughing money into this. From a pure strategic perspective, creating fuel-independent electrical power and heat anywhere on the planet is a game changer.
- AlbertCory 3y agoPossibly that ploughing money doesn't automatically produce results?
- jacknews 3y agoIndeed, compared to the number of fusion startups, which IMHO will be many decades if ever to be practical, and will never be economically viable, EGS could be operating economically, and deep/supercritical geothermal could be proven, in a decade or less.
- b112 3y agoand will never be economically viable While I do not disagree that it will be a ways off, never is a very long time. And the last century has seen so many things turn profitable, with scientific advances, presumption about the future seems inadvisable.
- jacknews 3y agoYes you are probably right, but still, IMHO compared to the alternatives, I think 'never' is reasonable for the currently envisaged, highly complex technologies and the still-unaddressed issues of fuel processing (eg tritium generation) etc, for mainstream power generation. I mean I can envisage solar being as cheap as dirt, roof shingles that are basically as cheap as slates. I can envisage geothermal getting cheap, it's just a hole in the ground. I can envisage fission getting cheap, eg the traveling-wave reactor is basically an enclosed lump of uranium. But rings of superconducting magnets and their controllers, along with radioactive lithium blankets that have to be renewed and reprocessed regularly, or gigajoule banks of lasers and little ultra-precision gold-wrapped fuel pellets? None of this stuff is ever going to be cheap, compared to the alternatives. It might find niche military, and of course, research use etc. And we might have a breakthrough in low-energy fusion or whatever, but the current crop are either scams or are simply never going to be viable.
- mjx0 3y agoOut of ignorant curiosity: I’ve heard that an anticipated problem of renewables is overproduction. i.e.: generators produce too much electricity, causing the grid frequency to exceed tolerance. How does one throttle a geothermal plant? Are these geothermal plants operating turbines, and thus are throttled by redirecting steam away from the turbines?
- megaman821 3y agoCouldn't they just not inject as much water into the injection hole? Then presumably the steam hole would stop making steam.
- pfdietz 3y agoThis sort of system has a kind of built-in storage. It can overproduce steam for a while, if needed, even if that level of steam production is not sustainable in steady state. This is nice for countering some short-term variability of other renewable sources, particularly solar.
- idiotsecant 3y agoYou're constantly throttling a steam turbine by admitting more or less steam.
- kodah 3y agoI'm curious how this will impact Radon release from deep areas of the crust. For context, a Radon risk map of the US: https://www.epa.gov/sites/default/files/2018-12/documents/radon-zones-map.pdf https://www.epa.gov/sites/default/files/2018-12/documents/ra... Uranium and Thorium decomposes into Radium, which themselves are found at 450m but the gas then rises through the Earths crust as it moves. I could see this kind of constant agitation releasing significantly more at least within a radius.
- kfarr 3y agoOr other fracking-adjacent risks like microearthquakes.
- joelthelion 3y agoAre these really that much of a problem if the wells are far from urban areas?
- jksk61 3y agoif they are too far away you'd have a loss of efficiency since I guess they'll transfer heat and not current, no?
- joelthelion 3y agoNot significantly if you are say 100km away.
- WarOnPrivacy 3y agoI've long wondered if a deep well geothermal utilitie would work for small to mid-sized neighborhoods. I've seen dedicated water and sewer utils for mid sized neighborhoods so that part of the equation seems okay. It should hinge on what energy calcs show.
- sofixa 3y agoFor what it's worth, there's a city in the Paris area, Champigny sur Marne, that is well suited for geothermal energy, and has a plant with a second one under construction, which provide heating and hot water to the adjacent neighborhoods. Sources in French: https://champigny-reseau-geothermie.fr/ https://champigny-reseau-geothermie.fr/ https://www.champignysurmarne.fr/grands-projets/geothermie https://www.champignysurmarne.fr/grands-projets/geothermie
- kragen 3y agothe crucial competitiveness problem for geothermal is that pv is now selling power at trading hubs in much of the world at 20 dollars a megawatt-hour (5.6 nanodollars per joule) while running a large heat engine driving a generator typically costs about that much at best, egs and other geothermal is free fuel to power a heat engine, but even if the drilling and fracking and whatnot costs zero dollars it is difficult for thermal energy to reach parity with current pv plausibly, future developments in manufacturing could do it, which is appealing because the geothermal resource is orders of magnitude larger than the terrestrial solar resource, but those developments can also make pv cheaper also, of course, pv is much less competitive in places like antarctica, england, or germany due to low capacity factor and long outages right now, though, new thermal power projects are relatively scarce
- dzdt 3y agoElectricity markets give widely varying prices thru the day. Even just thinking competition betweeen clean energy sources, in early evening peak hours geothermal wouldn't be competing with PV directly but rather PV via battery storage. The extra cost of batteries makes geothermal more cost competitive.
- kragen 3y agoit makes thermal power generation closer to cost-competitive, yes
- pbmonster 3y ago> In evening peak hours geothermal wouldn't be competing with PV directly but rather PV via battery storage And in many parts of the world, it would not be competing with PV at all during many days of winter, when cloud cover and incidence angle are so bad PV goes into single digit percentage of its peak output. Because then even batteries won't save PV.
- kragen 3y agomostly people don't live in those parts of the world, but you'll note my original comment does say 'pv is much less competitive in places like antarctica, england, or germany due to low capacity factor and long outages'
- tudorw 3y agoLong time coming, I visited this site when I was a young un, https://www.thinkgeoenergy.com/site-of-the-first-egs-project-in-the-1970s-for-sale-in-the-uk/ https://www.thinkgeoenergy.com/site-of-the-first-egs-project...
- jeffrallen 3y agoThe white paper says: "The stimulation fluid was a slickwater treatment design with a low-concentration friction reducer additive." I know secrecy like this is par for the course in fracking, but it would certainly help them escape the stigma of fracking if they broke the taboo and started talking clearly about what crap they are pumping down into the ground. I think if they said, "we put this much of this stuff down the hole", it would help to understand what the risks are. For more information about what might be in their fracking liquid, see: https://petrowiki.spe.org/Fracturing_fluids_and_additives#Fracture-fluid_additives https://petrowiki.spe.org/Fracturing_fluids_and_additives#Fr... The friction reducers are often "anionic copolymers". For more information about how the friction reducer polymer degrades in the environment, see: https://www.nature.com/articles/s41545-018-0016-8/#Sec5 https://www.nature.com/articles/s41545-018-0016-8/#Sec5 I would like to know more about this. Is an expert can chime in with better references than these, I'd be grateful to read them.