191–200 of 297 posts
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Just sell it though normal channels. If your battery is with more than your car then there would be people making money on the arbitrage.
I totally get that, but as the owner, perhaps I'd like to make the money on the battery before the arbitragers.
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The place I saw this most clearly described was in Standard Thermal's concept, which will store the heat in huge piles of dirt heated to 600 C. The thermal time constant of such piles can be many years. https://www.orcasciences.com/articles/standard-thermal-copy https://austinvernon.substack.com/p/building-ultra-cheap-ene... https://news.ycombinator.com/item?id=45012942
I ran the numbers on that, and it just doesn't work. Stone has rather lousy specific heat capacity (less than 1kJ/kg/K, compared to 4.2kJ for water). A typical house in Midwest needs around 22,000kWh (7.913×10^10 J) over the winter (75 million BTU - https://www.eia.gov/todayinenergy/detail.php?id=57321 ). If we assume the delta of 550 degrees (600 down to 50), you'll need: 7.913×10^10 J / (550K * 1000J kg^-1 K^-1) =…
A more worthy criticism is that the pile for just a single house is too small and would cool off too quickly.
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If I understand correctly, the cost/year of an engineer in India is maybe 1/3rd that in the US, and for general labor the disparity is even larger. So it shouldn't be too surprising NPP construction in India is cheaper than in the US. India doesn't have a large NPP pipeline, they just have cheaper labor.
(Bangladesh, not India) Yes, but solar power panels are also mostly produced in China, where engineers still get less than 1/3 of the US/Europe salary. European power plants will be more expensive, but even with the LCOE of 12 (twice that of Rooppur) it's still going to be way cheaper than storage for areas that get cold weather (Midwest, Germany, most of China). Anything south of California? Yeah, just get solar+win…
Storage is another matter here, but even there costs for batteries have simply collapsed. Understand that massive storage is needed even in a nuclear-powered economy. If all the 283 million cars and trucks in the US were replaced with 70 kWh BEVs, the storage would be enough to power the US grid (at its current average consumption) for 40 hours. That's a lot of batteries. So the demand is there to continue to drive them down their experience curves. In China, they're already around $50/kWh for installed grid storage systems (not just cell price).
The final storage problem, the only reed that nuclear can be clinging to at this point, is long term/seasonal storage. That's needed either to smooth wind variability (~ week scale) or to move solar from summer to winter (~6 months). There are at least two different ways this could be solved: hydrogen and heat. As mentioned elsewhere in these threads, the latter is very promising, with capex as little as $1/kWh of storage capacity and a RTE of about 40%. Should that work out anywhere close to that nuclear would be in a hopeless position anywhere in the world, even at very high latitudes.
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>Dunking on Tesla is its own industry these days, it seems. Are you suggesting Tesla is criticized without good reason ?
Idk enough but I assume there are good reasons, however when a website is biased and finds even bad reasons to hate that's still a problem right?
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Regulation is not a problem, and even the construction costs are not terrible. We can take the Rooppur NPP as a base, it produces reliable energy at 6-7 cents per kWh. The reason for cost overruns is simply because NPPs are one-off products, the Western countries don't have a pipeline for NPP production. For comparison, utility-scale solar with 16 hours of storage is 21 cents: https://www.utilitydive.com/news/higher-…
> The reason for cost overruns is simply because NPPs are one-off products But there's no fundamental reason they _have_ to be one-off products. They just historically have been for at least partly regulatorily motivated reasons: because each reactor's approval process starts afresh (or rather, did until quite-recent NRC reforms), there's little advantage in reuse, and because many compliance costs are both high and…
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There's currently no technological path for fusion to be cheaper than fission. It would require a technological breakthrough that we have not yet imagined. And already, solar plus storage is cheaper than new nuclear. And solar and storage are getting cheaper at a tremendous rate. It's hard to imagine a scenario where fusion could ever catch up to solar and storage technology. It may be useful in places with poor sola…
> It would require a technological breakthrough that we have not yet imagined. Maybe, but not necessarily. The necessary breakthrough might have been high-temperature superconducting magnets, in which case not only has it been imagined, but it has already occurred, and we're just waiting for the engineering atop that breakthrough to progress enough to demonstrate a working prototype (the magnets have been demonstrate…
And that's the problem with these Internet discussions: that's almost never the plan, but commenters trying to make solar look bad assume it is (to your credit, you made it explicit; many commenters treat it as an unspoken assumption).
In real life, solar and batteries is almost always combined with other forms of generation (and other forms of storage like pumped hydro), in large part due to being added to an already existing large-scale grid. The numbers that matter are for a combination of existing generation (thermal power plants, large-scale hydro, etc) with solar plus storage. Adding batteries for just a few hours of solar power is enough to mitigate the most negative consequences of adding solar to the mix (non-peaking thermal power plants do not like being cycled too fast, but solar has a fast reduction of generation when the sun goes down; batteries can smooth that curve by releasing power they stored during the mid-day peak).
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Still have mine. Battery capacity is around 80% of the new capacity. I'm not planning on switching anytime soon as it's got plenty of range still. I'll probably swap the pack out when it hits 70% in the next 2 or 3 years.
Your 2018 tesla has a battery SOH of 80%? How many km's on the clock, and how often do you fast charge if you dont mind me asking? To me that SOH stat sounds really bad!
If I were to guess, the main factor harming the battery is my garage gets pretty hot in the summer (37 or 38C)
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Your 2018 tesla has a battery SOH of 80%? How many km's on the clock, and how often do you fast charge if you dont mind me asking? To me that SOH stat sounds really bad!
I agree, reads like carefully crafted FUD.
To me this is perfectly reasonable degradation after 7 years of ownership with the number of miles I have.
There is also just an element of luck that's involved. Batteries degrade at different rates and there's not really any accounting for it.
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A thing I forgot to calculate: with 75m of wire dissipating 533 watts per meter, how thick should the wire be? Suppose we divide it into three 25m circuits so that we still have most of our heat if a wire burns out, and suppose we're using 48Vdc. So E ²/ R = 13.3kW, R = E ²/13.3kW = 0.173Ω, and each of those elements is carrying an astonishing 277 amps. So we want 7 milliohms per meter. It turns out that that's about…
Maybe stainless steel for the heating elements and busbars? Cheaper than nichrome and copper. I feel like mild steel would not last long in practice. Copper plated MIG welding wire might be good enough? Probably want to think about thermal expansion also, especially configured as "walls", and with skins considerably colder than cores.
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Yeah, we paid more for the little bits of metal that held up the panels than for the panels themselves (aluminum, but still).
IDK sounds like you got ripped off. I diy'd and panels were cheap of course, but fittings were perhaps 3-5x cheaper. Inverter is typically same as your panels (hybrid, grid-tied are quite a bit cheaper).
Unless you're just bolting them to the floor or to an uninsulated wall, mounting will (sadly) run you a sizable fraction of that cost in the best case.