Solar and batteries can power the world • Hacker News Board

Re: Solar and batteries can power the world

#161

Post by hamdingers » Fri, Apr 03, 2026, 4:09 PM UTC

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…

There's been a wave of legislation[1] introduced in the US to legalize so-called "balcony solar," small grid-tied solar systems that plug into a regular household outlet with zero permitting or interconnect requirements. This is already common in Europe, it's mildly complicated by our split-phase system but not much.

The reason for the high burden today is people have developed an inflated sense of how much the kWh they generate is worth. They install massive systems on their roofs to try to "cancel out" their power bill by exporting their entire daily power consumption over the course of a few sunny hours, which (when all their neighbors do the same) ends up being a costly burden for grid operators who then pass the costs on to users without panels. Smaller systems focused on immediate, local consumption rather than export are much better for the grid which is why they have support.

1. https://www.canarymedia.com/articles/solar/balcony-solar-tak...

Re: Solar and batteries can power the world

#162

Post by mft_ » Fri, Apr 03, 2026, 4:09 PM UTC

jwr wrote: post #49

No, they can't, not unless we get rid of the fossil fuel lobby, which pretty much runs the world these days. Which isn't surprising, given that fossil fuels are the largest industry ever created by mankind. If you compare it to anything else which was actively harmful and yet big money tried to convince you it wasn't (like tobacco, alcohol, or really anything else), there is nothing that huge. So it isn't surprising…

> 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, and coal/gas is the default option for filling the gaps left in the absence of timely and sufficiently rapid investment in other technologies.

Re: Solar and batteries can power the world

#163

Post by conorcleary » Fri, Apr 03, 2026, 4:09 PM UTC

jacquesm wrote: post #146

FEELmyAGI wrote: post #140

Earlier quoted context omitted.

What does the 1% of land used to grow corn have to do specifically with solar and batteries? Solar doesn't need to be on the 15% arable land at all. The corn doesn't just produce ethanol, which just utilizes the starch/sugar. The protein, fat, fiber is eaten by livestock in some form like distillers grains. And governments like to have food security , and having secondary uses for an abundance of food in the good tim…

My conclusion is that you didn't even try to understand the GP.

No no, that argument is pretty old now. The amount of fuel you GROW on your own continent at any single or double digit percentage during wartime-anytime is probably a good long-term research project that shouldn't be interrupted by people online.

Re: Solar and batteries can power the world

#164

Post by entropicdrifter » Fri, Apr 03, 2026, 4:10 PM UTC

hvb2 wrote: post #143

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…

> Scale that mindset problem up to a national grid and I imagine the challenge is the same. Except that we have raw data there? The only question is how fast it grows, but since we're transitioning that's mostly a question of how fast you decommission fossil plants.

Yeah, agreed. It's a lot easier to be empirical when the scale of the requirements is quite literally unimaginable without just dealing with raw numbers.

Re: Solar and batteries can power the world

#165

Post by germandiago » Fri, Apr 03, 2026, 4:10 PM UTC

Retric wrote: post #108

germandiago wrote: post #92

Earlier quoted context omitted.

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...

The economics only changed recently and infrastructure lasts a long time. It’s the same reason EV’s make up a far larger share of new car sales than a percentage of overall cars, EV’s sucked 20+ years ago yet there are a lot of 20+ year old cars on the road. The US stopped building coal power plants over a decade ago but we still have a lot of them. Meanwhile we’ve mostly been building solar, which eventually means w…

> 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 than that: that has more implications in conservative cultures where, whether you like it or not, showing "muscle" (wealth) is socially important for them to reach other soccial layers that will make their lives easier.

But giving up those things is probably a very bad choice for their living.

America cannot be compared to South East Asia economically speaking, for example. So the comparison of the coal centrals is not even close.

A salary in Vietnam is maybe 15 million VND for many people. With that you can hardly live in some areas. It is around 600 usd.

Just my two cents.

Re: Solar and batteries can power the world

#166

Post by lazide » Fri, Apr 03, 2026, 4:11 PM UTC

entropicdrifter wrote: post #164

hvb2 wrote: post #143

Earlier quoted context omitted.

> Scale that mindset problem up to a national grid and I imagine the challenge is the same. Except that we have raw data there? The only question is how fast it grows, but since we're transitioning that's mostly a question of how fast you decommission fossil plants.

Yeah, agreed. It's a lot easier to be empirical when the scale of the requirements is quite literally unimaginable without just dealing with raw numbers.

Germany’s renewables rollout would like a word….

Re: Solar and batteries can power the world

#167

Post by maxerickson » Fri, Apr 03, 2026, 4:12 PM UTC

brianwawok wrote: post #65

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…

In the short term the math is usually bad. Can be a 20, 30, 40 year payback on insulation. For the builder? It’s almost for sure a loss unless he can play the green card. For any individual owner? They are likely to leave before they recoup a project like this. Appraisals on houses are price per square foot with a bedroom and bathroom modifier. Until people start pricing in energy efficiency in homes, say a price mul…

I live in a moderately cold area and pay less than $2000 a year to heat a ~2000 square foot home. So something that improves the efficiency of the building would have to have a pretty low cost to even pay back at all.

There's probably a few lower cost things that I am overlooking, to the tune of netting out a few hundred dollars of savings after however many years they took to pay back.

Re: Solar and batteries can power the world

#168

Post by budududuroiu » Fri, Apr 03, 2026, 4:12 PM UTC

declan_roberts wrote: post #9

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."

China burns significantly more coal than the USA and Europe combined and has no environmental laws standing in the way of their nuclear power plants. Imagine a world where people don't care about labeling new things as "regressive" or "anti-environmental"

> China burns significantly more coal than the USA and Europe combined

Which is expected when both Europe and the US outsourced most manufacturing to China. It's actually surprising China is so low given they're literally the factory of the world

Re: Solar and batteries can power the world

#169

Post by FEELmyAGI » Fri, Apr 03, 2026, 4:13 PM UTC

jacquesm wrote: post #146

FEELmyAGI wrote: post #140

Earlier quoted context omitted.

What does the 1% of land used to grow corn have to do specifically with solar and batteries? Solar doesn't need to be on the 15% arable land at all. The corn doesn't just produce ethanol, which just utilizes the starch/sugar. The protein, fat, fiber is eaten by livestock in some form like distillers grains. And governments like to have food security , and having secondary uses for an abundance of food in the good tim…

My conclusion is that you didn't even try to understand the GP.

Then please explain, to me he brought up an unrelated point about ethanol (which is often poorly understood and mischaracterized anyways) consuming a portion of agriculturally productive land. Which BTW this agricultural land that produces ethanol is probably not even close to the best place in the country for industrial scale solar from a LOT of perspectives.

Re: Solar and batteries can power the world

#170

Post by proee » Fri, Apr 03, 2026, 4:14 PM UTC

EVs are essentially a giant battery on wheels. Seems there is a good opportunity to configure them as bidirectional power banks for your local grid. You could rewire all parking slots to have a plugin that acts as a bidirectional power station. Imaging how much power could be moved around with such a grid! This would require a major investment in power transmission layouts, but a city full of batteries on wheels.

California has registered around 1M Teslas alone. So this is like having a 1Mx80kwh = 80GWh battery at your service. As a reference, the largest solar + storage facility in California is around 3.2 GWh.