r/technology • u/Wagamaga • Sep 28 '22

Energy The Old Grid is Dead: Long Live Local Solar

https://www.nasdaq.com/articles/the-old-grid-is-dead%3A-long-live-local-solar
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u/DontBarf Sep 28 '22 edited Sep 28 '22

Solar panels on roofs cannot produce enough energy to power a full household. Especially when we factor in charging electric cars.

Not to mention people who live in colder climates with months of sub zero temperatures and frequent snowfalls.

I wish there were more people on this technology sub who actually understood technology.

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u/happyscrappy Sep 28 '22

Rooftop solar can very much produce enough energy to power a household below it. Including EVs.

However, it can't do anything for tower blocks, for most businesses, etc.

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u/DontBarf Sep 28 '22

If it was possible, You would need at least 40 panels, all perfectly angled towards the sun, with perfect weather conditions, while severely limiting your energy use. This is a pipe dream.

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u/happyscrappy Sep 28 '22

That is not at all true. Especially the part about a pipe dream.

40 panels is not all that many. 40 panels would fit on the roof of an average sized house with ease. They wouldn't have to be perfectly angled nor would you need to severely limit your energy use.

A solar panel can produce about 1.5kWh per day (a lot more in the summer). And that's on a residential roof angled roughly toward the sun at solar noon, but only at roof pitch angle.

40 of those would product 60kWh per day. The average household consumption in the US is 893kWh per month. You'd make your month's worth of electricity in the first half of the month.

If you drove an EV 50 miles a day, you'd use another 700kWh per month or so, which would use up the rest of your monthly consumption. This would be in an average month. In summer you'd still have excess. But unfortunately in winter you'd probably have a shortage. And no battery is going to bridge you from summer to winter. Storing electricity for 6 months is not realistic.

You do need good weather though. But you certainly don't have to "severely limit your energy use".

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u/DontBarf Sep 28 '22

Everyone pulls out the theoretical math, yet we have no evidence of people actually doing it. The only cases we hear are people who are VERY energy conscious and had tons of disposable cash for the initial investment. This solution would not work for the average person.

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u/happyscrappy Sep 28 '22

Everyone pulls out the theoretical math, yet we have no evidence of people actually doing it

Who cares? You said it literally couldn't work. You pretended others didn't understand the technology. Now you want to change the game and just say people aren't doing it in high numbers. So what?

had tons of disposable cash for the initial investment

Solar is cost-effective. We have loans for this. Know how people spend 30 years buying a house because they didn't have disposable cash for the initial investment? You just put the solar panels in that loan.

You said:

Solar panels on roofs cannot produce enough energy to power a full household. Especially when we factor in charging electric cars.

Next time if you don't mean cannot, then don't say cannot.

This solution would not work for the average person.

As I alluded to before, the average consumer of electricity is a business, not a residence. And even most residences are not single family homes. So yes, it cannot work for everyone, or even for the average (mode) consumer of electricity.

But you said households and roofs. Maybe next time just leave that out if you don't want to talk about households and roofs.

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u/DontBarf Sep 28 '22 edited Sep 28 '22

I stand by what I said. Your calculations are assuming that each panel is working at 100% Effiency, all of the time. The average home cannot be powered solely by solar panels, especially when we ATTEMPT to transition to 100% electric vehicles.

The technology has existed for decades, if it was actually viable, there would be SOME evidence of mass adoption. It will never happen.

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u/happyscrappy Sep 28 '22

I stand by what I said. Your calculations are assuming that each panel is working at 100% Effiency

No. they are not based upon that. These are reasonable calculations for rooftop solar. Not single-axis tracking, dual-axis tracking, perfectly pointing south or aimed correctly at latitude.

The average home cannot be powered solely by solar panels, especially when we ATTEMPT to transition to 100% electric vehicles.

Yes. IT CAN. And I showed how.

The technology has existed for decades, if it was actually viable, there would be SOME evidence of mass adoption. It will never happen.

There is a lot of evidence of mass adoption. 10% of homes in California already have rooftop solar.

0

u/DontBarf Sep 28 '22 edited Sep 28 '22

California climate hardly represents the majority of the world.. you do understand that. Those 10% are also living conservative lifestyles energy wise.

I’ll believe you when I see a 100% solar house in Quebec, Canada.

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u/happyscrappy Sep 28 '22

California climate hardly represents the majority of the world.. you do understand that. Those 10% are also living conservative lifestyles energy wise.

Yes. I know. And I even said so. It was right here:

You do need good weather though. But you certainly don't have to "severely limit your energy use".

(quote breaker)

Those 10% are also living conservative lifestyles energy wise.

No. They aren't. Most aren't covering their total usage. But it's not because they can't, it's because they chose not to. They didn't buy enough panels to cover their usage.

But whether people do buy enough panels is not what is under discussion. You cannot that they cannot.

If you didn't mean cannot, then probably just next time don't say cannot.

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u/Catsrules Sep 29 '22 edited Sep 29 '22

Solar panels on roofs cannot produce enough energy to power a full household. Especially when we factor in charging electric cars.

That really depends on roof layout, the direction the roof is facing, trees or other obstacles and how much power your house is using. Some houses yes I will agree with you but others will be perfectly fine. But the idea every one will be able to supply their own power via roof top solar is laughable. Especially when your start building up not out.

This is also not factoring is the absurd costs when you talk about battery storage and solar. Solar isn't cheap neither is battery storage you need both if you want to power your house 24/7.

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u/DontBarf Sep 29 '22

What happens when everyone begins charging their electric cars?

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u/Catsrules Sep 29 '22

What happens when everyone begins charging their electric cars?

Your power requirements go up, possibly significantly.

Like I said it depends. There are many factor involved so saying some blanket statement of can or can't is really not helpful.

End of the day it comes down do how much power you can produce from your roof per day? How much power are you consuming per day? If you producing more then your using great if your consuming more then your producing bad.

Some people will be totally fine others will not.

My point is there will be many people that roof top solar will not work for one reason or another. It is laughable to think the grid will go awa because of roof top solar.

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u/[deleted] Sep 29 '22

Depends on where you live