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Solar and batteries can power the world

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Re: Solar and batteries can power the world

#381

Post by tsoukase »

PyWoody wrote: post #31
declan_roberts wrote: post #5

The article is just wrong. And only mentions energy used for heating in passing. Heating requires MASSIVE amounts of energy. I should know bc I have a whole house battery and solar system (almost 30 kWh battery and 24kW solar). It keeps the lights on, but not heating. I live in a mild climate. The reality is that battery/solar requires major quality of life and activity time shifting trade-offs.

I live in a northern climate and I know multiple people who are net zero with solar+basic battery. Proper insulation and good windows go a very long way. For instance, I set my heat to 66F during the day and 60F at night. When I wake up in the morning, the register is usually still above 60F.

These temperatures are non negotiable by my wife. Women will burn the planet.

Re: Solar and batteries can power the world

#382

Post by uecker »

lazide wrote: post #355
uecker wrote: post #339

Earlier quoted context omitted.

Germany has more wind in winter, so traditionally has more production of renewables in winter months.

It has dramatically higher thermal heat demands in winter - far higher than is compensated for by that. Even if everyone switched to heat pumps.

True, but higher demand for heating in winter is not specific to Germany. In the end, Germany will likely need to import energy anyway - just as it does today. But this means this question may not be the most relevant.

Re: Solar and batteries can power the world

#383

Post by panick21_ »

RandomLensman wrote: post #29
panick21_ wrote: post #16

Nuclear could have powered the world easily and we could have done it with 1960s technology. And we could easily do electricity and heating with nuclear quite easily. The only thing that's actually tricky is synfuels and solar/battery doesn't solve that. High temperature reactors using heat to create hydrogen is arguable the better path to synfuels then electrolysis. And we can go to 100% of electricity from nuclear,…

Nuclear reactors make awful targets in a conflict, not sure having many around is generally a good idea if conflict is a risk and there are alternatives.

For many nations that is really not the primary reason to choose infrastructure. And even if that is your goal. Then building a 500MW reactor you can drop in the ground is likely a pretty decent solution.

Re: Solar and batteries can power the world

#384

Post by ViewTrick1002 »

panick21_ wrote: post #344
ViewTrick1002 wrote: post #196

Earlier quoted context omitted.

The problem is the economics. They’re just horrifyingly expensive to build. The equivalent to each new large scale reactor in GWe requires tens of billions in subsidies. The next problem comes from incentives. Why should anyone with solar or storage buy this expensive grid based nuclear electricity? Why should their neighbors not buy surplus renewables and instead pay out of their nose for expensive nuclear powered e…

The French have used their nuclear system for 20+ years as a giving tree. The forced EDF to sell nuclear at very cheap prices to fossil fuel companies and then buy it back at much higher price. The French forced EDF to give subsides to solar even when that actually hurts their economics. The French randomly in the 2010s decided to replace nuclear in a short time-frame (completely 100% unrealistic) but it sounds good…

People disliking renewables always say this.

Then when asked what method to price in the Swedish nuclear fleet having ~50% of capacity offline multiple times last year and France famously having 50% of the capacity offline during the energy crisis I always get crickets for answers.

It’s apparently fine when nuclear plants doesn’t deliver, but not renewables.

The difference with renewables is that it’s even easier to manage. Their intermittency is entirely expected and the law of large numbers ensure we never have half the capacity offline due to technical issues at the same time.

> Once you think on a systemic level, how to provide reliable energy for a whole country, nuclear is not more expensive and France saved a huge amount of money buy doing what they did.

Given that new built nuclear power costs 18-24 cents per kWh and won’t come online until the 2040s what you’re trying to tell me is that multiplying the current electricity cost 3-4x and creating a self made energy crisis isn’t so bad.

The French made a good choice half a century ago. The equivalent choice in 2026 are renewables and storage.

Just look at the proposed EPR2 fleet. A 11 cent per kWh CFD and interest free loans. Summing up to over 20 cents per kWh for the electricity. With the first reactor coming online at the earliest in 2038.

It’s just complete insanity at this point.

> All this new energy transfer infrastructure is incredibly expensive. It cost at least as much as the generation itself, and sometimes more.

The 10 GW HVDC links being built costs €20B. That’s equivalent to the subsidies needed for one new large scale reactor. Then you have the market price of electricity on top of that.

Are you starting to realize the conundrum?

Re: Solar and batteries can power the world

#385

Post by timbit42 »

eldaisfish wrote: post #307
orthecreedence wrote: post #222

Earlier quoted context omitted.

> 1:10 or 1:15 electric:heat energy ratios Under what circumstances? I've seen higher-end units that do maybe 1:5 in ideal conditions (heating to 68F when the ambient temp is 55F), but never seen units that do 1:10 or 1:15. This was about 2-3 years ago I did this research. Have things improved that drastically in the last few years?

things have not improved. Too many folks here do not understand or care to appreciate the constraints of the real world. Heat pumps are excellent and relatively cheap but have limitations. One of the biggest limitations is that a heat pump's efficiency drops as ambient temperature drops. This is the worst possible situation for heating as the conditions when the risks of losing heat are the highest, are precisely the…

As long as they remain more efficient than resistive heaters down to the lowest temperatures you experience, it's a win. Heat pump efficiency is still improving. You can get heat pumps that can handle down to -35°C now with even better ones in the works.

Re: Solar and batteries can power the world

#386

Post by mft_ »

jwr wrote: post #181
mft_ wrote: post #162

Earlier quoted context omitted.

> Germany shifted from nuclear to coal and gas Sure, but you're attributing this, deliberately or not, to the wrong cause. It wasn't that the fossil fuel industry somehow won - it was range of factors possibly including geopolitics, some existing plants aging, an emotional response to the Fukushima nuclear disaster, and the Green lobby. Basically, they voted to kill nuclear without a solid plan for an alternative, an…

Hmm. After former chancellor (Schroeder) heavily pushed Russian gas pipelines (Nord Stream 1 and 2) and then swiftly moved to working for Russian state-owned energy companies, including Nord Stream AG, Rosneft, and Gazprom, I have a different outlook on things.

One can never discount lobbying and influence behind the scenes, but Schroeder finished being Chancellor in 2005, which was six years before the initial post-Fukushima vote in question, and even longer since various aspects of the plan continued to be supported by various politicians.

He'd be a spectacularly successful lobbyist if your suspicion is correct.

Re: Solar and batteries can power the world

#387

Post by ZeroGravitas »

mikewarot wrote: post #316

It's important to note that electricity is 21% of the World's energy demand, according to the IEA[1]. This implies that if we could 10x solar, and figure out how to convert some of that to liquid fuels with decent efficiency, we could become sustainable for all energy. [1] https://www.iea.org/world/energy-mix

2/3rds of that other 79% is wasted as unwanted heat, so we only need to replace 1/3rd of 79% (~26 percent points) so slightly more than double the current clean energy supply.

An extensive explanation of this "primary energy fallacy":

https://ember-energy.org/latest-insights/reframing-energy-fo...

Re: Solar and batteries can power the world

#388

Post by pfdietz »

kogasa240p wrote: post #377
pfdietz wrote: post #291

Earlier quoted context omitted.

You mean gravity batteries using concrete weights? A scam for suckers.

Nope: https://news.mit.edu/2025/concrete-battery-now-packs-ten-tim...

So, about two orders of magnitude lower specific energy than Li-ion batteries. The extra cost per kg had better be damned small or this won't pencil out.

Re: Solar and batteries can power the world

#389

Post by mullingitover »

tialaramex wrote: post #334
mullingitover wrote: post #201

Earlier quoted context omitted.

Not one man, he's financially backed by the wealthiest people in the world and politically supported by millions. Acting like this blunder is some random stroke of bad luck isn't telling the whole story.

Trump's animus against wind in particular is definitely specific to the man. He was annoyed by a wind farm in Scotland. Trump of course thinks he's one of those old fashioned kings† (and the US has been annoyingly willing to go along with that, how are those "checks and balances" and your "co-equal branches of government" working out for you?) and so he thought the local government would go along with his whims and p…

Trump’s campaign had financial backing from a number of oil and gas industry investors. Following the money in this case is not very difficult. He’s just a useful idiot, the whole industry put him there and are profiting at the expense of the rest of us.

Re: Solar and batteries can power the world

#390

Post by majoe »

mtoner23 wrote: post #38
PyWoody wrote: post #31

Earlier quoted context omitted.

I live in a northern climate and I know multiple people who are net zero with solar+basic battery. Proper insulation and good windows go a very long way. For instance, I set my heat to 66F during the day and 60F at night. When I wake up in the morning, the register is usually still above 60F.

Net zero. But not effectively zero. They sell energy during the day when no one needs it and buy it an night when we all need it. If we all switched to solar and heat pumps there would be blackouts and an energy crisis

Some thoughts on why I think this is wrong:

If no one needs it during the day, they can't sell it. That's not how markets work. Energy that is generated, needs to be consumed or else the grid breaks down. These two facts together mean, that the energy they sell is needed and used. Albeit they could generate and sell even more energy, if the energy could be stored or if the load could be shaped accordingly. The latter is a great way to lower energy costs.

Energy consumption during the night is low. So low, that night time electricity prices, which are lower than the daytime prices, are still a thing.

Heat pumps are an opportunity for load shaping. Buildings can be heated, when electricity is abundant and heated a few degree over the target temperature, if needed. The heat is stored inside the building and needs less heating during the night. That works quite well, especially here in Europe were buildings generally have good insulation and are made of brick, which can store a lot of heat.

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