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Power

US Startup To Supply 320 MW Geothermal Energy To Power 350,000 Homes In California (interestingengineering.com) 44

An anonymous reader quotes a report from Interesting Engineering: Fervo Energy has announced the signing of two power purchase agreements (PPAs) totaling 320 MW with Southern California Edison (SCE), one of the nation's largest electric utilities. The two PPAs, signed for 15 years, will provide clean, and affordable power for the equivalent of 350,000 homes across Southern California. The geothermal energy from Fervo will help California transition to a cleaner and more reliable power source. According to Fervo Energy, SCE will purchase the power from its 400 MW Cape Station project currently under construction in southwest Utah.

The first 70 MW phase of Fervo Energy's project is expected to be operational by 2026 and the second phase will be operational by 2028, according to a release by the company. Geothermal energy, being a carbon-free and weather-agnostic source, will also prove to be a reliable source for meeting California's power consumption demands. Unlike wind and solar power plants, geothermal energy can be sourced around the clock and on demand to cater to increased energy needs.

Earlier in July 2023, Fervo Energy had claimed to achieve "commercial scale" geothermal energy production from its Project Red demonstration site in northern Nevada. [...] For the demo, Fervo had used a horizontal well pair that extended to 3,250 feet (990 m) and reached a temperature of 375 degrees Fahrenheit (191 degrees Celsius). During the test period, Fervo achieved a flow rate of 63 liters per second, sufficient to generate 3.5 MW of electricity. One megawatt of energy can power approximately 750 homes at a time. Data collected during this pilot was used to improve the design for Fervo's next well pair and double the energy output generated.

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US Startup To Supply 320 MW Geothermal Energy To Power 350,000 Homes In California

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  • âoeOne megawatt of energy can power approximately 750 homes at a timeâ

    So how is 320MW powering 350M homes?

    That seems to only support 240M homes

    • And if any site admin actually read the site any more, this is only 20 years old:

      https://www.joelonsoftware.com... [joelonsoftware.com]

    • 350M homes doesn't even make any sense, since that's more than the population of the US and there are fewer homes than individuals. But I don't know where you're seeing it so I guess they edited the summary after you posted.

      The math in the summary still doesn't work, but not by that much.

      • M means one thousand in many industries. One million is MM. oneiros27's use of it right after MW where the M is for mega ie a million is confusing though.

        My industry uses MBF for lumber... one thousand board feet.

        • Yup, so many odd units out there in industry. I have seen the M==1000 used in some contexts, mostly American. Gas meters use CCF, for Centi-Cubic-Foot (centi==100), mostly because CF would spin the dial too fast.

          • by smithmc ( 451373 )
            "centi" = 0.01, not 100. (E.g. centimeter, 0.01 m not 100 m) The "C" in this case is actually "centum", which is Latin (or Roman numeral) for 100. Which is even weirder,,,
        • by smithmc ( 451373 )
          Maybe, but in general parlance in America, M = million (mega) and K = thousand (kilo).
    • "One megawatt of energy can power approximately 750 homes at a time."

      So 1000 KW is supposed to power 750 homes, so 1.33 KW per house. At optimal conditions like right now on an early summer day that might be true, at least until the water heater kicks on its 5 KW heating element.

      The heat pump compressor alone takes 7 amps at 240 V, so that is 1.7 KW and doesn't count either the indoor or outdoor fans. An average winter day takes about 60 KWh for my all electric house, that's 2.5 KW on average. A particularl

      • It might just be an annual average consumption. It's a fair calculation only so long as all the energy can be consumed whenever it is produced (you have natural gas plants and the question is how much you'll reduce fuel use).
      • Average vs peak. A typical* home might draw 20kW or more with all the appliances running. But on average, draw about 2 to 5kW over a 24 hour period. This is what makes power/energy comparisons so difficult to understand for the average person (hopefully not for the average Slashdotter, who is apt to just whip their slide rule out). And it is prt of the reason that we need either storage or spinning reserve generation on our grid. Even for old fasioned thermal sources.

        *Lots of these average numbers are base

      • Does your water heater run the heating element 24/7? You should get that looked at if it does.

        Does your heat pump compressor always yank that 240V@7A or do you think that once it's in motion it might step down the current draw like every other electric pump or motor in existence?

        Are you running your electric stove or oven for hours and hours overnight while you sleep?

        The numbers are averages. You are pointing to peaks that lie above the mean, completely ignoring the overnight hours when usage is far below

        • The heat pump compressor always draws 6 or 7 amps, as it should since it's always compressing the same flow up to the same differential pressure. It is not always on except on very cold days, and the resistance heaters turn on too. A standard 8 ft baseboard is two kilowatts.

          The water heater does cycle on and off, but the load when on is the load when on.

          Right now, as I speak, the only thing on is the refrigerator and a couple of trickle charges. So right now half a KW is probable all I'm drawing. That does

        • As the electric bill just came in the mail, last month came out to 1.1 KW on average for the month. No heat, no AC needed.

          Last winter the coldest month came in right on 3 KW averaged over the month.

          So if they stipulate that 1.33 KW is to run a house Not Including heating and cooling loads then I would be happy with their claim.

    • by necro81 ( 917438 )
      I wouldn't read too deeply into the math. Like just about all news outlets, they are conflating the terms "energy" and "power" and their related units.

      "One megawatt of energy can power approximately 750 homes at a time"

      Which is another way to say: they don't really understand what they're talking about.
    • Haha. The power company will happily throttle the power that the "homes" are using.

  • They must upgrade the grid, more copper
    • I'm sure they will get it from D'Anconia Copper.
      • The density disadvantage of copper can be circumvented by hanging the conductors from a messenger strand of Rearden Metal.
        • I think that's an excellent idea! Now, if the fair share law only allowed manufacturing of those hangers.
    • Re:the grid (Score:4, Informative)

      by ShanghaiBill ( 739463 ) on Friday June 28, 2024 @08:57AM (#64585129)

      They must upgrade the grid, more copper

      Long-distance transmission lines often use aluminum rather than copper.

      The cross-section needs to be about 60% more to compensate for the lower conductivity, but aluminum is much cheaper, so it's usually worth it.

      • Long-distance transmission lines often use aluminum rather than copper.

        The cross-section needs to be about 60% more to compensate for the lower conductivity, but aluminum is much cheaper, so it's usually worth it.

        Also very important since these transmission lines are suspended is that the density of aluminium is 2.7, but copper is 8.96 so even with 60% cross-section it is half the weight.

        Given its higher cost and greater weight I am not sure copper is ever used in long distance transmission lines. Every line description I have seen used aluminium.

        • by Whibla ( 210729 )

          Given its higher cost and greater weight I am not sure copper is ever used in long distance transmission lines. Every line description I have seen used aluminium.

          Copper is currently used in the long distance undersea DC interconnects between the UK and several countries in Europe, some of which are ~280 km long. I am not entirely sure why they don't use aluminium for these as well, but I'm sure there are compelling technical / financial reasons for it.

          Hopefully someone more informed than me can explain...

      • Long-distance transmission lines often use aluminum rather than copper.

        And not so long distance as well. It's usually aluminium right up to the meter on your house. And then into your breaker panel.

  • The article makes a big deal about how geothermal energy can provide "base load" power. This is interesting after seeing so many advocates for renewable energy make the claim that base load is a myth or is an outdated concept with today's technology. I guess some people finally figured out that we can't just keep throwing batteries at the problem, there needs to be some minimum amount of reliable 24/7 electricity production on the grid if we are to keep the lights on.

    • The article makes a big deal about how geothermal energy can provide "base load" power.

      TFA mentions "base load" but describes it incorrectly.

      You don't want "base load" to complement renewables. You want dispatchable power that can be quickly ramped up or down to fill in the troughs when renewables drop off.

      Geothermal works reasonably well as dispatchable power if it's combined with a steam buffer and/or molten salt reservoir.

  • ... geothermal energy is ultimately nuclear.

    The heat escaping from the core of the earth has more than one source - a lot of it [wikipedia.org] comes from decay of radioactive minerals.

    • by XXongo ( 3986865 )

      ... geothermal energy is ultimately nuclear. The heat escaping from the core of the earth has more than one source - a lot of it [wikipedia.org] comes from decay of radioactive minerals.

      So is solar energy, ultimately coming from nuclear fusion. In fact, I've hears some of the people you'd probalby call "greens" say that the best location for a nuclear power plant is 95,000,000 miles away.

      Wind energy is also nuclear, of course. Coal, too. In fact, every power source you can name ultimately sources from a nuclear reaction of one sort or another.

    • ... geothermal energy is ultimately nuclear.

      About half of it is due to radioactive decay. The other half is from the self-gravity heat of forming the Earth in the first place. [wikipedia.org]

  • by xack ( 5304745 ) on Friday June 28, 2024 @09:26AM (#64585197)
    We would have more than enough power if people didn't keep mining stupid coins.
    • My grandpappy worked down in the coin mines, it was good work if you could get it. Spend most of the day pedaling stationary bicycles to drive the turbines. Pay wasn't good but he'd supplement it by charging phone batteries on the side. At the end of the week the workers would have parties with their bootleg kombucha, and talk about the old days when coins were so plentiful you could find them on the ground.

  • According to some of the news posted here recently, it looks like California already has all the energy it needs from the solar. Why to bother with this geothermal stuff?
    • by Tablizer ( 95088 )

      cuz we plan 4 more ev's

    • Because energy demand isn't static over time?

      Because diversification is a good idea?

      Because distributed generation is a good idea in a state that occasionally has natural disasters such as wildfires, floods, earthquakes, landslides, etc. ?

  • There is a lot of distance between Utah and California. There will be a big difference between what goes into the grid in Utah and what comes out in California. This seems like a good application of something like high voltage DC transport.

    • It already exists, and has since 1986 [wikipedia.org]. "Path 27" is a high-voltage DC intertie capable of delivering 2400MW from Delta, UT to Adelanto, CA and the power plant in Utah only has a nameplate capacity of 1900MW and California isn't getting all of it. There's capacity available without doing anything but plugging the proposed geothermal plant in.

  • A giant geothermal power plant(s) could bleed off heat near Yellowstone, delaying the likely eventual eruption of a super-volcano that would be a roughly 10x bigger disaster than Covid. And give us tons of power to boot.

    However, doing it wrong could trigger it earlier, such as upsetting a fragile balance of lava pressure.

  • by Gravis Zero ( 934156 ) on Friday June 28, 2024 @11:05AM (#64585443)

    So I checked out Fervo Energy [wikipedia.org] and they seem to be using an enhanced geothermal system (EGS) [wikipedia.org] which is a type of geothermal power that will induce seismic activity. Not great but it's still better than coal or natgas.

    • by habig ( 12787 )

      Thanks for the link, nice to see how it actually works.

      I'm wondering how much heat can be pulled out of a borehole before it's cooled enough to not work so well anymore? Having worried about cooling systems underground trying to get heat out, it turns out that rock's conductivity isn't all that great: can't use it as a heat sink, and we have to find other ways to get the heat out to the surface. So, pull the heat out of around your borehole, how quickly does heat flow back in from the surrounding rock? T

  • TFA says the pilot project generated 3.5 MW using 63 l/s of water (at, I assume, 190 C, the only temperature reported in the summary. They didn't say they achieved 191 C at 63 l/s so YMMV.) That's about 55 kJ per liter. Water has a specific heat of 4.2 kJ/l-C (that's per liter-degree Centigrade) so dividing means you had to extract only about 13 C from each liter.

    That seems surprisingly small. I didn't think even cooling the water to 20 C would yield enough energy. Turns out that would yield 10x more than t

  • Fervo's one of two exciting companies at the moment; there's also Eavor, that proved fracking-type techniques could not only produce baseload power, but actually store energy by pumping down water under higher pressures. And I think a third, Sage, is getting some good results in their pilots.

    This news is basically that the "pilots" are over and the first-generation pioneer production plants are being tried. If it works with fair prices at scale:

    If we can produce baseload power almost anywhere, and indeed

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