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Solar and batteries can power the world

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Re: Solar and batteries can power the world

#151

Post by turtlebits »

ronb1964 wrote: post #130

I build off-grid camper vans for a living and install solar + lithium battery systems regularly. The technology has matured a lot in the last few years. What used to take a massive roof array and a bank of heavy lead-acid or AGM batteries to run basic appliances now fits in a fraction of the space with lithium. The limiting factor in real-world installs isn't the panels or the batteries anymore, it's getting customer…

While I agree with underestimating capacity, the problem only really applies to off grid.

For regular homes, it just means less savings.

Re: Solar and batteries can power the world

#152

Post by caseysoftware »

declan_roberts wrote: post #94
blackcatsec wrote: post #66

Earlier quoted context omitted.

They've fallen victim to a catastrophically easy scare tactic, unfortunately. "The sun only shines during the day therefore solar is bad!" Dumb, but easy.

And in my experience as someone who is actually trying to DO something, is exactly right. But to be clear, it's less about night vs day and more about summer vs winter.

^ This.

I had a 20kWh array and 18kWh of batteries in Texas and it was GREAT in the summer. It'd start charging by 6am and be charged by 9am, even with simultaneous usage. Then we'd live off solar for the day (even with HVAC), go back on batteries around 9pm and they'd be out around 4am. No problem.

But during an overcast winter day, the stack wouldn't get power until 8/9, not make it to 50%, start discharging by 4/5pm, and be out by 10/11pm. It would easily be 8-10 hours where we were wholly dependent on the grid.

Not a problem, just a constraint to acknowledge and plan for.

Re: Solar and batteries can power the world

#153

Post by jacquesm »

declan_roberts wrote: post #59
toasty228 wrote: post #39

Earlier quoted context omitted.

People still build houses like energy is cheap and abundant. A properly insulated house in any temperate climate require very little heating or cooling. Spend 50k on insulation that will last the life of the building instead of 50k on heating and cooling devices which will need constant maintenance and replacement + fuel and end up costing 10x more over the life of the building. A modern house with modern insulation…

Yes you're right and I don't disagree. But a 500w heater isn't going to cut it when it's 20F outside. You actually have to run the heat as hard as possible when the sun is shining so you have some thermal momentum going into the evening. The end result is you're going to make big lifestyle changes to accommodate the energy. For example everyone sleeping in 1 bedroom and only cooking with an electric pressure cooker o…

You could put that 500W into a heatpump.

Re: Solar and batteries can power the world

#154

Post by aidenn0 »

rickydroll wrote: post #126
aidenn0 wrote: post #90

Earlier quoted context omitted.

I could not retrofit my house for efficient heating with $50k. To do so would likely be cheaper to completely tear it down and rebuild.

same here. 1940's house with slate roof and vermiculite "insulation". You can't just use modern insulation techniques or blown-in foam because that would make exterior wood rot. You need to keep the air flowing the right way to dry out the wood.

I have to clean the eaves of my house myself because nobody I hire will believe me that you can't point a pressure washer at the eaves without water getting inside the walls. "I'll just avoid the vents" doesn't work when you can see daylight between the roof and the wall all around the house.

Re: Solar and batteries can power the world

#155

Post by lazide »

turtlebits wrote: post #151
ronb1964 wrote: post #130

I build off-grid camper vans for a living and install solar + lithium battery systems regularly. The technology has matured a lot in the last few years. What used to take a massive roof array and a bank of heavy lead-acid or AGM batteries to run basic appliances now fits in a fraction of the space with lithium. The limiting factor in real-world installs isn't the panels or the batteries anymore, it's getting customer…

While I agree with underestimating capacity, the problem only really applies to off grid. For regular homes, it just means less savings.

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.

Re: Solar and batteries can power the world

#156

Post by davyAdewoyin »

balderdash wrote: post #91
mbesto wrote: post #41

Fun fact, 12 million hectares of land of used to produce corn used for ethanol which is used to produce gas. I'll let you draw the conclusion. https://news.cornell.edu/stories/2025/04/trading-some-corn-e...

I’d rather people went rooftop solar, and put that land to producing food.

It's a common mistake to believe there isn't enough land to grow food, and that is simply false. We throw tons and tons of food away every year due to spoilage and other factors. Even in many parts of Africa scarcity of food is caused by waste and distribution problem than simply lack of arable land.

And when you think about the millions of lands used to grow bioethanol I think we can safely convert that for solar installation without worries.Agrovoltaic is also a practical approach for a lot of crops and farmers so that we can grow and produce electricity side by side.

Re: Solar and batteries can power the world

#157

Post by 0xbadcafebee »

ahhhhnoooo wrote: post #2

China understands this, parts of the EU understands this. The US is currently dead set on betting on the wrong technology, and it's going to put them so far behind. Imagine a world where people didn't care about labeling new things "woke", and instead could all sit down and say, "we're going to make major investments in next generation infrastructure to ensure our capacity and independence."

They're not anti-renewables as a bet, they're anti-renewables strategically. If you like going to war, you can power your warfighting apparatus much easier with a gas tank than a battery. If you want better defense, you don't depend on hostile nations for your energy needs. The US wants to double down on oil because it likes to fight wars and it's paranoid about defense.

Re: Solar and batteries can power the world

#158

Post by legitster »

Retric wrote: post #99
legitster wrote: post #72

By 2050 is the important caveat. That's assuming constant production of batteries at the current scale and production. It also assumes we figure out how to economically recycle materials from batteries (and total recovery may never be possible). Grid scale lithium batteries have an effective lifecycle of 15 years. In this potential future, global lithium reserves would actually start getting choked up before the 2050…

We already have an electric grid we don’t need to build a new one from scratch just replace infrastructure that gets to old and add more for whatever extra demand shows up. Obviously other energy sources are going to exist and non solar power will be produced, but nuclear is getting fucked in a solar + battery heavy future. Nuclear already needs massive subsidies and those subsidies will need to get increasingly larg…

Nuclear costs are massively skewed by the compliance costs.

Reactors that only took 5 years to build before ALARA are still safely running 80 years later. The 15-20 year build and certification time for new reactors is purely made up. The countries that are building our battery and solar pipeline (China, South Korea, Japan) are all building nuclear domestically at 1/3 of the cost of us.

More importantly, for cobalt and lithium - we still exclusively rely on natural raw resources that are still very cheap. Meanwhile we have established reserves of fissile material for thousands of years.

Maybe it won't be in the near future, or even in our lifetime, but there is no way the human race does not turn to nuclear eventually.

Re: Solar and batteries can power the world

#159

Post by gpm »

balderdash wrote: post #128

Just my 2c but I think the biggest thing we could do is to reduce the regulatory burden, cost, and complexity associated with installing roof mounted solar. This should be something that can be approved and installed in a week, and should be a half the price (put another it should have a double digit roi) . Right now all of the economics of home solar are consumed by regulation/complexity and the contractors / solar…

At the consumer scale the biggest thing we could do is follow the german model of panels that can be plugged into an outlet and installed in an hour by any homeowner (with the same capacity limits and requirements on the panels electronics to protect the grid/line workers during power outages).

That said I'm pretty sure that grid-scale solar is the future of most solar energy, not home solar. It's just cheaper to do things in bigger batches.

Re: Solar and batteries can power the world

#160

Post by doctoboggan »

germandiago wrote: post #92
anon7000 wrote: post #61

Earlier quoted context omitted.

Yeah, the technology connections video on this was fantastic. If one was to cover that land in solar, you’d produce far more than the current energy demands of the US. Relying on an energy source which requires constant, continuous resource extraction is fucking stupid when we can spend resources up front and get reliable energy (solar + battery) for decades with minimal operating cost & maintenance. And then we’ll h…

So here I go: if it is so stupid, why it is not done yet? Try not to blame anyone. Do it rationally if you can, from your message I understand your opinion. I say this as a person that has lived in a developing country the last 15 years. It is not that simple IMHO...

Based on your response timestamp I will conclude you didn't watch the video. He "does it rationally" like you requested. You said "try not to blame anyone" so if you'd rather not hear about the people who actually are to blame for this situation, then skip the last 30 minutes of the video.
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