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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

#331

Post by katkatkatkatket »

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 around 100GW. Assuming a capacity factor of 5 (which is probably far too low), the power transmission system needs to handle at least 500GW. The current (and somewhat unproven) state of the art in power transmission operates at 1000kv, and can carry 5GW per pylon system. We would need 100 of those operating in parallel. As each of those has a minimum separation corridor of 100 meters, we would need to persuade all of the countries along the route to give us a 4000km x 10km strip of land, as well as the approx. 150sq km of land needed for the panels themselves.

This leads to another fun question - if you want to install 150sq. km of solar panels in the desert and still have enough useful life left in the panels when you're done, how wide does the road need to be to carry all of those, and how many trucks will you need working that several thousand km route?

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

#332

Post by pfdietz »

SV_BubbleTime wrote: post #318
pfdietz wrote: post #274

Earlier quoted context omitted.

Because they are too expensive and take too long to build. One gets much more CO2 reduction per $, and much more quickly, from spending on renewables.

Regulated one to be too expensive, subsidized the other to be cheap. The arguments against nuclear are always a direct result of the previous set of arguments rooted mostly in panic, lack of education, and three small scope issues that range from unlikely to impossible now. But yea. You are right, we made nuclear too expensive to be viable.

The arguments against nuclear are based on long history of economic failure. The same tired excuses are always trotted out. It's all someone else's fault.

Money talks, shit walks. The captains of industry and finance are treating nuclear like the failure it is. No money for this money pit.

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

#333

Post by adrianN »

TheLoafOfBread wrote: post #124
whimsicalism wrote: post #102

Earlier quoted context omitted.

Energy storage

Could you be more specific? Because battery energy storage barely works for houses and you can't build pump storage everywhere. Then there are few prototypes like Power-To-Gas which has promising prospect and rest is in level of sci-fi

Power to gas, as you mention, would be sufficient. There are also some interesting battery chemistries in the pipeline, like iron-air batteries. How about we keep building renewables at a rapid pace until we actually have enough to need storage? Until then we have time to improve storage technology and build some electrolyzers (we'll need lots of Hydrogen anyway for industrial purposes).

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

#334

Post by jnsaff2 »

Helmut10001 wrote: post #320

People both underestimate and overestimate what PV can do. In summer and around noon, here in western Europe, there is so much PV-electricity produced that it is _almost_ enough to fulfill all demands. In winter, the amount is like a drop in the desert. I have built a 30 kWp PV at home 2 years ago - you would think this is quite big, for a private plant. It is not enough. If I want to power a heat pump (with drilled…

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.

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

#335

Post by hedora »

scaramanga wrote: post #249

As in many times more solar panels than can be constructed with all of the resources that can possibly ever be extracted from the earth? I suppose that is true, and an be verified with some pretty simple back of the envelope calculations. I must admit, I only skimmed through the apparently meaningless technobabble, but if someone could let me know succinctly, we still don't have anything more effective at carbon sequ…

Capturing a gallon of gasoline CO2 emissions from the atmosphere would cost about a dollar at scale. (1 gallon -> 20lbs CO2. Technologies advertising $100/ton of CO2 are somewhat common these days. A ton is 2000lbs, so $100 / ton CO2 implies $1 per gallon of gasoline). There are many technologies that could achieve this, but I don’t think this article is describing one of them.

They want to convert CO2 and water to natural gas and have roughly 30% energy efficiency. A gallon of gas contains 33kWh, so (handwave gasoline == natural gas), it costs 100kWh per gallon equivalent. A kilowatt hour is at least $0.10, so > $10 per gallon-captured-ish.

If the carbon intensity of natural gas is similar to gasoline, so the computation is close enough and the technology in the article is about 10x off state of the art.

On the bright side, the article’s technology would “only” require 5% of the earth’s surface be covered in solar panels, so state of the art would need 0.5%, which is feasible, in terms of land use, at least.

Carbon intensity table: https://www.forestresearch.gov.uk/tools-and-resources/fthr/b...

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

#336

Post by Helmut10001 »

jnsaff2 wrote: post #334
Helmut10001 wrote: post #320

People both underestimate and overestimate what PV can do. In summer and around noon, here in western Europe, there is so much PV-electricity produced that it is _almost_ enough to fulfill all demands. In winter, the amount is like a drop in the desert. I have built a 30 kWp PV at home 2 years ago - you would think this is quite big, for a private plant. It is not enough. If I want to power a heat pump (with drilled…

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 the country, you usually have space (but lack money), in the city, you lack space but can often work with a pretty good income (= build a new, energy optimized house).

Every house is different. If I build a new house today, of course this would look different.

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

#337

Post by zbrozek »

outworlder wrote: post #27
fermentation wrote: post #5

In every game of Factorio I've played I didn't realize just how many solar panels I'd needed until I was hitting my power limits and in desperate need of more. The problem being that manufacturing these takes... power.

Yes but... In Factorio, the only cost is the original manufacturing costs. The same goes for storage. Once manufactured and placed, they will produce power forever as long as it is daylight. The capacitors will also last forever. There are no weather patterns to mess up production. In other words, once you make one, you have a permanent power increase. Your power can grow exponentially if you just focus on building a…

I'm currently keeping half of a quite large (and horribly leaky) house perfectly pleasant with a midsized solar array, a portable air conditioner, and a fan. Zero grid draw.

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

#338

Post by cycomanic »

WalterBright wrote: post #188
Aeolun wrote: post #186

Earlier quoted context omitted.

> that we would have better results right now? Think of the shareholders! All that lost value could have gone to line their pockets, but instead it’s being used for the good of society (to be fair, probably to those same shareholders through different companies at exorbitant rates).

> All that lost value could have gone to line their pockets, but instead it’s being used for the good of society That is indeed the pitch the communists make. How is that working out for them?

Show me any large scale infrastructure project that has been realized by private enterprises without massive government subsidies. How is your privately funded highway or rail system working out for you?

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

#339

Post by dmitriid »

jnsaff2 wrote: post #334
Helmut10001 wrote: post #320

People both underestimate and overestimate what PV can do. In summer and around noon, here in western Europe, there is so much PV-electricity produced that it is _almost_ enough to fulfill all demands. In winter, the amount is like a drop in the desert. I have built a 30 kWp PV at home 2 years ago - you would think this is quite big, for a private plant. It is not enough. If I want to power a heat pump (with drilled…

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.

> 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.

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

#340

Post by mtlmtlmtlmtl »

hobofan wrote: post #327
mtlmtlmtlmtl wrote: post #314

Earlier quoted context omitted.

Not sure why this is downvoted. Either advertising is effective to some degree, in which case banning it would necessarily help curtail consumption. Or it's ineffective, in which case it would necessarily save a ton of wasted resources and man hours. I would happily defend the position that advertising does more harm to society than good, if anyone is willing to reply in good faith instead of just cowardly downvoting…

It's downvoted because its a broad populist statement that isn't actionable in that form and doesn't provide any value to the discussion. In contrast your take is a lot more nuanced and something that actually can serve as a basis for fruitful discussion. Banning advertisment outright is about as realistic as banning humans from communicating.

That's fine, but pointing that out, like you did now and providing a cogent reply like I tried to almost always leads to interesting discussions, I've found. The trolls run away at the first sight of real discussion anyway, most of the time.
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