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We're going to need a lot of solar panels

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Re: We're going to need a lot of solar panels

#381

Post by katkatkatkatket »

katkatkatkatket wrote: post #331
walrus01 wrote: post #4

We're going to need a lot of solar panels and an efficient way to transport power from a very sunny place to another location where the loads are. For instance: https://en.wikipedia.org/wiki/Pacific_DC_Intertie The pacific DC intertie right now often ends up being used to transport power from hydroelectric dams in WA/OR to California. But there's nothing to say that something couldn't function the other way if there…

>The technology now exists to theoretically cover many hundreds of square km of Libya in photovoltaics and take the electricty to Europe It really doesn't. I'm a huge fan of back-of-the-envelope maths, and this idea raises some very fun questions. How big would the power line be, if the UK (where I live) was powered entirely by solar panels in the African desert? The UK's average instantaneous power consumption is ar…

I'm out by two orders of magnitude on the amount of desert solar needed to power the UK. It's more like 13000 sq km, comprising approx. 7e9 solar panels. If they weigh 30kg each, and two-trailer road trains are used to transport them, that's 2e5 truck loads.

The sheer scale of this logistical problem dwarfs any other feat attempted.

Re: We're going to need a lot of solar panels

#382

Post by dmitriid »

jnsaff2 wrote: post #347
dmitriid wrote: post #339

Earlier quoted context omitted.

> With all due respect, looking at your numbers my hunch is that you need better insulation. With all due respect these are the kinds of "tiny" details that renewable enthusiasts conveniently forget. Yes, this person's house needs better insulation. As does everybody else's . You can't just wave this away with "your math is wrong". These numbers reflect reality, not wishful thinking.

I wish you would expand and clarify the point you are trying to make. Currently it sounds like you are angry at a group of enthusiasts. I think for me and the OP it’s quite clear that optimizations can be made on production and consumption side. And in their circumstances financial reality says that increasing production is much cheaper, while possibly providing extra cash that would enable investment for reducing co…

> I wish you would expand and clarify the point you are trying to make.

The problem with people enthusiastically proposing renewables as the cheap solution to our energy needs is the thousand "little" details like the one above. Whose only mention is in the comments like "your math is wrong, invest in insulation".

No. The math isn't wrong. Bo, the consumption is correct and shouldn't "should be lower". Because it's directly indicative of the reality.

Yes, you have a couple of enthusiasts who can sink another X kiloeuro into rebuilding their house. For the absolute vast majority of users it's not a viable option.

So yes, the answer to "PV energy is almost enough in summer and not nearly enough in winter" isn't a dismissive "you're doing insulation wrong".

Also https://news.ycombinator.com/item?id=32201039

Re: We're going to need a lot of solar panels

#383

Post by fauigerzigerk »

katkatkatkatket wrote: post #331
walrus01 wrote: post #4

We're going to need a lot of solar panels and an efficient way to transport power from a very sunny place to another location where the loads are. For instance: https://en.wikipedia.org/wiki/Pacific_DC_Intertie The pacific DC intertie right now often ends up being used to transport power from hydroelectric dams in WA/OR to California. But there's nothing to say that something couldn't function the other way if there…

>The technology now exists to theoretically cover many hundreds of square km of Libya in photovoltaics and take the electricty to Europe It really doesn't. I'm a huge fan of back-of-the-envelope maths, and this idea raises some very fun questions. How big would the power line be, if the UK (where I live) was powered entirely by solar panels in the African desert? The UK's average instantaneous power consumption is ar…

We wouldn't want to import all our electricity from one country anyway, even if that country wasn't quite as unstable as Libya.

A more realistic option for the UK might be a submarine HVDC link to Morocco, sort of a bigger version of Viking Link project, which connects the UK to Denmark. I'd like to know if the technology exists to imort, say, 5% of our electricity via that route.

Re: We're going to need a lot of solar panels

#384

Post by lrem »

illiac786 wrote: post #376
KingOfCoders wrote: post #356

Earlier quoted context omitted.

Not sure how "better insulation" is something "renewable enthusiasts conveniently forget". We need better insulation either way.

I think what this person meant is the renewable enthusiasts treat insulation as something easily done whereas it will take 100 years to insulate the majority of houses in Europe in my view…

Much of eastern Europe, so not particularly rich or well run countries, went from zero (due to cheap Russian gas in Warsaw pact) to ~everything insulated (because trying to cut dependency on a mortal enemy) in less than two decades.

Re: We're going to need a lot of solar panels

#385

Post by dmitriid »

illiac786 wrote: post #376
KingOfCoders wrote: post #356

Earlier quoted context omitted.

Not sure how "better insulation" is something "renewable enthusiasts conveniently forget". We need better insulation either way.

I think what this person meant is the renewable enthusiasts treat insulation as something easily done whereas it will take 100 years to insulate the majority of houses in Europe in my view…

Thank you. I couldn't have phrased it this well

Re: We're going to need a lot of solar panels

#386

Post by dmitriid »

lrem wrote: post #384
illiac786 wrote: post #376

Earlier quoted context omitted.

I think what this person meant is the renewable enthusiasts treat insulation as something easily done whereas it will take 100 years to insulate the majority of houses in Europe in my view…

Much of eastern Europe, so not particularly rich or well run countries, went from zero (due to cheap Russian gas in Warsaw pact) to ~everything insulated (because trying to cut dependency on a mortal enemy) in less than two decades.

I'm from Moldova. No, they didn't go to "everything is insulated" even in the wildest dreams.

Re: We're going to need a lot of solar panels

#387

Post by geertj »

katkatkatkatket wrote: post #331
walrus01 wrote: post #4

We're going to need a lot of solar panels and an efficient way to transport power from a very sunny place to another location where the loads are. For instance: https://en.wikipedia.org/wiki/Pacific_DC_Intertie The pacific DC intertie right now often ends up being used to transport power from hydroelectric dams in WA/OR to California. But there's nothing to say that something couldn't function the other way if there…

>The technology now exists to theoretically cover many hundreds of square km of Libya in photovoltaics and take the electricty to Europe It really doesn't. I'm a huge fan of back-of-the-envelope maths, and this idea raises some very fun questions. How big would the power line be, if the UK (where I live) was powered entirely by solar panels in the African desert? The UK's average instantaneous power consumption is ar…

Any such system would probably use DC, which would be much more compact than what you describe.

Re: We're going to need a lot of solar panels

#388

Post by bryanrasmussen »

Helmut10001 wrote: post #336
jnsaff2 wrote: post #334

Earlier quoted context omitted.

With all due respect, looking at your numbers my hunch is that you need better insulation. I know a person who has about 10kWp installed on a passivhaus here in latitude 59N and says that having a heat pump is overkill for them.

Yes, absolutely - the house is a pretty big country side house from 1925, not uncommon in Germany. But (almost) impossible to insulate efficiently. My estimates where €150k to €200k, just for the insulation, windows, and renewed heaters. In comparison, an 'oversized' 70 kWp PV only costs €100k, and also returns some income when not all of the power is used. The parameters widely differ between country and city: In th…

yeah, there are so many old houses are still sitting around in Europe. My area almost every house was built in the late 1800s. Looks pretty nice, but insulation sucks.

Re: We're going to need a lot of solar panels

#389

Post by 10u152 »

opo wrote: post #317
walrus01 wrote: post #234

Earlier quoted context omitted.

You're definitely not going to power all of NYC by rooftop solar, but also look at the size of the warehouse roofs (empty, no solar) in NJ just across the river, and out on long island. And Staten island. Etc. Empty land is not necessarily a requirement. Parking lot per-row shade structures that integrate PV panels on top are also a thing now, and there are sure a shitload of parking lots in NJ and out on long island…

Rooftop solar is far more expensive than solar put on land. The cost of rooftop solar (particularly homeowner solar) is usually hidden by implementing a big subsidy to wealthy consumers that is paid for by less wealthy consumers - sort of a reverse robin hood scheme. We are well past the point where anyone can argue we should subsidize rooftop solar because we need to help build a fledgling industry - yet I see solar…

Why is rooftop solar more expensive?

Mounting structure is there, grid supply is there, no issues with weeds/grasses, generally up in the air etc.

Rooftops are unused space.

Re: We're going to need a lot of solar panels

#390

Post by bryanrasmussen »

hgomersall wrote: post #351
dmitriid wrote: post #339

Earlier quoted context omitted.

> With all due respect, looking at your numbers my hunch is that you need better insulation. With all due respect these are the kinds of "tiny" details that renewable enthusiasts conveniently forget. Yes, this person's house needs better insulation. As does everybody else's . You can't just wave this away with "your math is wrong". These numbers reflect reality, not wishful thinking.

Well yes, but generally renewable enthusiasts are also saying "we need to improve our housing stock". That's another of the opportunities to improve people's lives that will come through necessary change.

surely 'improving housing stock' will require a lot of energy expenditures that might not be easy to calculate what the actual benefits are.
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