Solar and batteries can power the world • Hacker News Board

Re: Solar and batteries can power the world

#31

Post by PyWoody » Fri, Apr 03, 2026, 3:25 PM UTC

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.

Re: Solar and batteries can power the world

#32

Post by Tade0 » Fri, Apr 03, 2026, 3:25 PM UTC

declan_roberts wrote: post #17

cbdumas wrote: post #11

Earlier quoted context omitted.

The article is about utility scale solar and storage I believe not home installations. It also mentions towards the end that in cold norther climates adding wind to the mix makes sense

Like I said he grossly understates the energy demand we use in the United States for heating during the winter.

I believe a lot of that demand is due to there being no incentive to increase energy efficiency.

Re: Solar and batteries can power the world

#33

Post by outside1234 » Fri, Apr 03, 2026, 3:25 PM UTC

pfdietz wrote: post #3

Providing 90% of power is not "powering the world". It really helps to also have a complementary storage technology with low capacity capex, even if the round trip efficiency is lower. This would complement batteries in the same way ordinary RAM complements cache memory in a computer.

The goal of getting to renewables is to not remove every carbon source but to slow the rate of change so we can adapt. 90% meets that.

Re: Solar and batteries can power the world

#34

Post by mtoner23 » Fri, Apr 03, 2026, 3:25 PM UTC

teucris wrote: post #12

pfdietz wrote: post #3

Providing 90% of power is not "powering the world". It really helps to also have a complementary storage technology with low capacity capex, even if the round trip efficiency is lower. This would complement batteries in the same way ordinary RAM complements cache memory in a computer.

The article specifically notes the following: >We can get far without worrying about the last 5-10%. The solutions for the last 5-10% could be fossil fuels in the short-term, long-duration storage as it matures, or easily storeable e-biofuels.

So then they are wrong. The last 5-10 percent is the hardest part and it's the one consumers complain the most about! You can't run a factory on 90% power availability

Re: Solar and batteries can power the world

#35

Post by lstodd » Fri, Apr 03, 2026, 3:26 PM UTC

iamjake648 wrote: post #10

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.

Do you have a high efficiency heat pump, or how are you heating?

First question should be: what latitude?

Because where I live around 55th this winter we had five straight weeks below -15c / 5f daily average plus enough snowfall that it was infeasible to clean anything but the most major roads.

Solar is out of question in these conditions and when thermal pump fails you have to evacuate. When just grid electricity fails you have to either have some sort of stored fuel backup or evacuate.

The article is typical handwavy crap which is popular among people living in what amounts to subtropics who can't even imagine how crazy they sound to most everyone else.

Re: Solar and batteries can power the world

#36

Post by Rover222 » Fri, Apr 03, 2026, 3:26 PM UTC

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.

Well obviously lights aren't using up much of that power, you're powering everything else too.

Re: Solar and batteries can power the world

#37

Post by PyWoody » Fri, Apr 03, 2026, 3:27 PM UTC

j16sdiz wrote: post #14

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.

The insulation matters a lot in home heating.

Proper windows make a huge difference, too.

Re: Solar and batteries can power the world

#38

Post by mtoner23 » Fri, Apr 03, 2026, 3:27 PM UTC

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.

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

Re: Solar and batteries can power the world

#39

Post by toasty228 » Fri, Apr 03, 2026, 3:27 PM UTC

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.

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 a mild climate shouldn't even need a central heating system. You can get by with 500w toaster heaters in each room for the coldest time of the year

Re: Solar and batteries can power the world

#40

Post by declan_roberts » Fri, Apr 03, 2026, 3:28 PM UTC

Epa095 wrote: post #23

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.

What's the actual effect you get out of that? Even half, 12 kW, would be an absolutte beast of heating (for a home), even with 'dumb' convection heating. With heat pumps 2-3 kW should really be enough.

There's simply not a lot of sunlight to go around during the winter and the battery capacity isn't large enough.

Keep in mind we WFH and homeschool so our house is used 24/7 and I think it's a good approximation for OP's goal.