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Solar and batteries can power the world

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Re: Solar and batteries can power the world

#351

Post by asdff »

laurencerowe wrote: post #349
asdff wrote: post #330

Earlier quoted context omitted.

>The net energy output is only around 1.3 so an acre of corn produces maybe 400 gallons of gasoline equivalent output requires 300 gallons of gasoline equivalent in energy inputs. What is the problem, that sounds great? 30% free output out of your input is staggering honestly. Thank you sunshine and atmospheric CO2. You don't have to use fossil fuel for this. You can potentially run the farm equipment off ethanol if…

Opportunity costs essentially. The effort that goes into growing and refining corn ethanol could be better spent on reducing fuel consumption instead of dedicating five acres of land to provide the equivalent net yearly fossil fuel consumption of a single average car using 500 gallons of gasoline to drive about 15000 miles.

Why not do both, reduce fuel consumption while shifting to a carbon neutral fuel source that is fully onshored?

Re: Solar and batteries can power the world

#352

Post by asdff »

WillAdams wrote: post #346
asdff wrote: post #332

Earlier quoted context omitted.

Why would you use diesel as input when you are making fuel? Just use part of the fuel you are making as input for the next crop.

We will have to see if Deere's new tractor which runs on E98 actually makes it to market. The blunt question is: >How many calories of energy to grow 1 calorie of corn (using modern industrial farming practices)

Another commenter said this ratio is 1.3 in favor of output.

Re: Solar and batteries can power the world

#353

Post by asdff »

gus_massa wrote: post #145
kogasa240p wrote: post #82

Earlier quoted context omitted.

Damn I didn't know it was that bad. Ideally you'd grow algae from sewer waste and make fuel from that, but this is the US we're talking about.

Algae needs solar light, so you will have to flood a lot of land to get enough. Also, in case of a war or blockade you can switch the corn use from etanol to food. You will have to eat tortilla and polenta for a year [1] but it's better than algae from seawater or famine. Here we use sugar cane to produce etanol, it's more efficient because it's a C4 plant. I guess it's possible in the south of the US. [1] It's not s…

>Algae needs solar light, so you will have to flood a lot of land to get enough.

Algae is farmed at industrial scales in the ocean, today. Mostly in asia. US is very behind on this industry.

Re: Solar and batteries can power the world

#354

Post by 0wis »

esseph wrote: post #219
chrisBob wrote: post #194

Earlier quoted context omitted.

People acclimatize pretty well if you let them. We keep our house at 65F all winter, and set the AC for 85F in the summer and everyone is pretty happy. The payback period on a good sweater is not very long.

85?!? I've lived in extremely cold and extremely hot/humid places. I cannot imagine setting the temp in the house that high.

Setting for command is different from actual temp. Plus, humidity is rarely accounted for. A good AC that lowers humidity from 90%+ to 30% and this 30°C home becomes quite comfortable.

Re: Solar and batteries can power the world

#355

Post by lazide »

uecker wrote: post #339
lazide wrote: post #155

Earlier quoted context omitted.

It means some other infrastructure (fossil fuels?) needs to take up the slack, and people underestimate actual costs at larger scales. It’s the big issue in Germany for instance - it’s all fun and games until Winter.

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.

Re: Solar and batteries can power the world

#356

Post by asdff »

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'm not sure how sustainable it is at scale but I know someone who winters off a woodburning stove. They basically get their wood for free from trees that come down in their yard or people's yards that they know. They use a hydraulic woodsplitter to manage splitting all the wood.

Re: Solar and batteries can power the world

#357

Post by jopsen »

philipkglass wrote: post #295
germandiago wrote: post #165

Earlier quoted context omitted.

> The economics only changed recently and infrastructure lasts a long time This needs investment also. An investment poorer people cannot or do not want to do. It is reasonable that when someone gives up a couple of things because that person is rich (rich as in a person in the developed world) the sacrifice is more or less acceptable. Now change environment and think that these sacrifices are way worse. Even worse t…

Unlike the US, Vietnam is a net importer of fuel. It imports over 40 million tons of coal per year: https://statbase.org/data/vnm-coal-imports/ It also started importing liquid natural gas in 2023. But it has abundant sunlight, access to low cost Chinese solar panels that will produce electricity for decades instead of being burned once, and a substantial domestic photovoltaic manufacturing industry of its own. "Rene…

Add cheap labor to the equation.

In developed countries 20-50% of the cost of roof top solar is labor.

Re: Solar and batteries can power the world

#359

Post by subhobroto »

enslavedrobot wrote: post #348
subhobroto wrote: post #335

Earlier quoted context omitted.

> Besides direct subsidies, wealthier home owners have often been paid the retail rate for the electricity they sell to the grid. This causes higher electricity bills for those in apartments and those who can't afford to put panels on their roof I don't think you thought this up yourself, so I won't blame you for it, as this exact, word for word swill is mindlessly repeated by a lot of people, so thats ample evidence…

I have some experience with distributed energy generation and have met with senior utility executives many times while trying to implement some grant supported projects through my work. It turns out that a big problem is that whenever we install local generation it costs utilities a ton of money. They bundle the cost of grid maintenance into their per kWh charges. These costs, which include debt service, maintenance,…

> It turns out that a big problem is that whenever we install local generation it costs utilities a ton of money

So a question:

- Lets hypothesize that distributed, decentralized systems cost way more than centralized systems

- If you agree with that hypothesis, can we next hypothesize that building a distributed, decentralized system that can support power on one block and can allow it to continue to stay on while the "central feeder line" (please tell me the proper word for this made up word is) to all the blocks is down, because that one block has a local distributed, decentralized power source, is of value to the community?

In the past, commercial factories were the only places that could afford this kind of redundancy but it feels to me, thanks to crashing prices of solar and batteries (I could never have imagined 12kWh brand new LFP could be purchased for $2k), this level of redundancy is now very much realistic at the consumer, residential level. It just doesn't work locally today because the utility poles lack the smarts to do the isolated switching and safe islanding. For example: one unsettled question today is if a lot of customers on one such island are on solar and the grid is down, how do we safely supply power within nominal specs to the whole of the island - but this isn't a physical unknown, we know how to solve it. It just is lacking implementation.

> These costs, which include debt service, maintenance, upgrades etc amount to 5-7 cents/kWh. Whenever you generate your own energy you cost the utility 5-7cents/kWh that they have to pay regardless of your usage

Capitalism has repeatedly proven its ability to cut costs down while improving QoS. I realize you really believe in the numbers you have been provided - that it costs a utility 5-7cents/kWh that they have to pay regardless of my usage, but before SpaceX, it used to cost multiple millions of dollars and years of planning and design to launch one rocket.

Re: Solar and batteries can power the world

#360

Post by tialaramex »

gpm wrote: post #223
nradov wrote: post #207

Earlier quoted context omitted.

We haven't been building much battery storage to go along with that solar power. Perhaps we will eventually, but until that actually happens the base load requirement represents a hard limit on the amount of solar generation capacity that the grid can handle.

We started scaling batteries after solar (because the technology reached the point where they were profitable after solar)... but they're being installed at scale now, and at a rapdily increasing rate. Batteries provided 42.8% of California's power at 7pm a few days ago (which came across my social media feed as a new record) [1]. And it wasn't a particularly short peak, they stayed above 20% of the power for 3 hours…

I think the mysterious "Misc" electricity which sometimes appears at dawn and then dusk in the UK is likewise BESS†. The raw data doesn't seem to have labels for BESS, a lot of it was oriented around how electricity works twenty five years ago, there's an 850MW power plant here, and one there and one there, and we measure those. So it can cope with a wind farm - say 500MW or 1GW coming ashore somewhere, but not really with the idea that there's 10GW of solar just scattered all over the place on a bright summer's day and the batteries might similarly be too much?

† My thinking is: Dawn because in a few hours the solar comes online, you can refill those batteries at whatever price that is, so sell what you have now for the dawn price, and Dusk because the solar is mostly gone but people are running ovens and so on to make food in the evening, so you can sell into that market. But I might be seeing what I expect not reality.

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