281–290 of 297 posts
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What are the bad reasons that bias electrek’s coverage?
Electrek's Fred has a ton of Tesla referral credits. Tesla owes him 2 Roadster's and has reneged. After Tesla screwed him, Fred's coverage turned from glowing to negative.
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> And nuclear is scalable if you force other sources off the grid in favor of nuclear (and force customers to not use renewables "behind the meter"). Not really? Nuclear is not any different from coal. And plenty of countries have coal generation in the mix. France also is majority-nuclear. And so far, nuclear is the second known technology (after hydro) that actually demonstrated close to 100% fossil-free grid. So f…
Nuclear is quite different from coal. First, coal has a much larger share of its cost as variable cost which is avoided if you don't run the plant. 40% for coal, only 10% for nuclear. This makes integrated a coal fired plant into a renewable grid easier than a nuclear plant. China is increasingly doing this with its coal plants. Second, coal is much more forgiving of maintenance sloppiness, and even in the event of c…
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> And nuclear is scalable if you force other sources off the grid in favor of nuclear (and force customers to not use renewables "behind the meter"). Not really? Nuclear is not any different from coal. And plenty of countries have coal generation in the mix. France also is majority-nuclear. And so far, nuclear is the second known technology (after hydro) that actually demonstrated close to 100% fossil-free grid. So f…
Nuclear is quite different from coal. First, coal has a much larger share of its cost as variable cost which is avoided if you don't run the plant. 40% for coal, only 10% for nuclear. This makes integrated a coal fired plant into a renewable grid easier than a nuclear plant. China is increasingly doing this with its coal plants. Second, coal is much more forgiving of maintenance sloppiness, and even in the event of c…
Nuclear power plants have similar behavior to coal plants in another regard, they take approximately the same time to ramp up/down.
> You are aware that a nuclear plant tripping offline was part of the cause of ERCOT's last winter cold problem?
They just need to build more of them. Problem solved.
Anyway, nuclear power plants went from 0% to 70% generation in France within 20 years in 70-s. We don't see anything like this happening with solar, even in smaller island countries. Solar is successful only when it's backed by fossil fuels and government subsidies to keep that fossil fuel generation running.
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Nuclear is quite different from coal. First, coal has a much larger share of its cost as variable cost which is avoided if you don't run the plant. 40% for coal, only 10% for nuclear. This makes integrated a coal fired plant into a renewable grid easier than a nuclear plant. China is increasingly doing this with its coal plants. Second, coal is much more forgiving of maintenance sloppiness, and even in the event of c…
The nuclear power plant wear-and-tear is roughly proportional to the number of hours it runs at full power. By not running the plant, you can extend its service life (probably to more than 100 years, with periodic annealing). The main limiting factor is the reactor vessel, its steel walls can only tolerate so much neutron bombardment before becoming too brittle for service. Nuclear power plants have similar behavior…
The technical ability to ramp up/down is beside the point; it's the financial ability to do so that matters.
What nuclear did in France half a century ago is irrelevant. What matters is if nuclear makes sense today. It doesn't, even if it could be done.
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Oh, really? What temperatures do US power plants operate their steam at?
Here's an article giving the state of such plants in the US in 2011. Since then I imagine some of the smaller/older plants have been retired. There is no new coal capacity coming online in the US. https://www.powermag.com/coal-fired-generation-cost-and-perf...
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Residential batteries are not that expensive anymore, at least not all of them. That's a misconception I also held until a few years ago ;-) My first 14.3 kWh pack cost about 2800$ DDP from China, delivered 03/2023. For that one I did calculate how long it took for amortization, which I projected at about 5 years. The second, identical pack was delivered 08/2024 and cost 2000$ DDP. Since we got an EV that's drawing a…
My new batteries were about 250EUR/kWh - my 10KWh unit cost 2500 EUR - scaling it up to a decent used 5 year old EV price - you can have one for 15k with 60+ kWh batteries, so I'd say it's at a very similar price.
If you don't work from home it makes 0 sense either.
IMO we are long way from proving V2G usefulness. Micromanaging your car SOC every night to save $2 is nuts.
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In addition to my sibling comment: The cost of the panels is a rather small fraction of the total cost of a typical installation. Most of that cost ist labor, some regulatory requirements and the inverter. Whether you pay a factor of 2 for the panels or not typically doesn't matter. In other words: Reusing used panels will only ever be able to safe you a minuscule amount.
These days it’s a stack of microinverters. Which are not cheaper but do improve array efficiency outside of idea conditions. But that’s another up front cost.
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Here's an article giving the state of such plants in the US in 2011. Since then I imagine some of the smaller/older plants have been retired. There is no new coal capacity coming online in the US. https://www.powermag.com/coal-fired-generation-cost-and-perf...
Sounds like it was 80% subcritical at the time. I hadn't realized. It sounds like even "regular supercritical steam" is at like 580°, though. Maybe dirt at only 600° could still provide a substantial fraction of its stored energy to subcritical steam circuits, if they're much colder than that?
Imagine a pile with long pipes through it. Cool fluid is introduced at one end; the steam is gradually heated as it travels down the pipes, emerging as hot steam at the end. If needed, gang two of these together with the second pile acting to top off the temperature from the first one (or more than two).
So, during discharge, a wave of cold sweeps down the pile(s), while the pile near the outlet end stays pretty hot. Only when most of the piles are discharged does the temperature decline.
The Standard Thermal approach is described as heating the piles with embedded resistive heaters, but it could also use an external heater that sends in steam in the opposite direction from when it discharges. This would turn the system into a giant counterflow heat exchanger. Counterflow heat exchangers are known for their high performance, enabling almost all the delta-T between two fluid streams to be interchanged.
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Sounds like it was 80% subcritical at the time. I hadn't realized. It sounds like even "regular supercritical steam" is at like 580°, though. Maybe dirt at only 600° could still provide a substantial fraction of its stored energy to subcritical steam circuits, if they're much colder than that?
I think "storage at 600 C" could provide most of its heat output at close to 600 C. It's not like the entire thermal store is tapped at the same time. Imagine a pile with long pipes through it. Cool fluid is introduced at one end; the steam is gradually heated as it travels down the pipes, emerging as hot steam at the end. If needed, gang two of these together with the second pile acting to top off the temperature fr…
The only drawback is that, when you're heating the pile, most of the time you are only heating part of it (the cold part), so your heating elements need to have a significantly higher power capacity, assuming you're heating the pile with embedded resistors as described, rather than with a heat transfer fluid as you suggest.
I don't think you want the heat transfer fluid in the dirt pile to be steam; that would involve making the pipes through the hot dirt resistant to both pressure and steam corrosion, which would make them expensive. It also means you'd have a high-pressure steam leak deep inside the dirt pile when they did fail, which would probably cause damage to other pipes and to resistors and a significant uncontrolled heat transfer from the zone of the leak to other parts of the dirt pile. I think you want a more relaxing atmospheric-pressure heat transfer fluid that allows you to use cheap pipes, or even no pipes. Air, for example. Solar salt can reach those temperatures, and it has a much larger heat capacity, but it's fairly corrosive.
For a seasonal thermal store, also, we're talking about astoundingly low power densities, so low-density heat transfer fluids like air should be fine. If we're cooling the hot dirt from 600° down to 100° over a 3-month low-sun season, and the dirt is 1J/g/K, we're only extracting 63 watts per tonne, which at 1.3 tonnes of dirt per cubic meter is 80 watts per cubic meter. My human body is largely air-cooled and generates about 800 watts per tonne in normal operation, even without forced air.
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The nuclear power plant wear-and-tear is roughly proportional to the number of hours it runs at full power. By not running the plant, you can extend its service life (probably to more than 100 years, with periodic annealing). The main limiting factor is the reactor vessel, its steel walls can only tolerate so much neutron bombardment before becoming too brittle for service. Nuclear power plants have similar behavior…
Sure, you can save some maintenance cost by operating at low capacity factor. But this is a minor part of the cost of nuclear energy, so you don't save much. Nuclear simply isn't constituted to be useful as a dispatchable source. The technical ability to ramp up/down is beside the point; it's the financial ability to do so that matters. What nuclear did in France half a century ago is irrelevant. What matters is if n…
Nuclear plants do not degrade at a constant rate, regardless of their power. By idling the plant, you extend its service life, essentially amortizing the capital cost over a longer period of time. And the capital cost is the main driver in the cost of the nuclear power, as you're pointing out yourself.