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Satellite powered estimation of global solar potential

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Re: Satellite powered estimation of global solar potential

#101

Post by sneak »

jjcm wrote: post #7
ben_w wrote: post #5

Nice to see, I hope it helps people get more cheap energy. All I have are nits to pick: > 10.7k TWh globally This brings back memories of the time I almost shortened "thousand kilometres" to "kkm". Also, and this is not a criticism of Google, the IEA link on that text looks suspiciously like the IEA is still forecasting linear deployment of PV between 2025 and 2035, despite at least a decade of people pointing at it…

> 10.7k TWh globally Agree I hate this, but at the same time I don't know if I would have groked it correctly on first read if it had listed "10.7Pwh globally". We simply aren't exposed to numbers at that scale on a regular basis. Not sure what the correct solution is here.

Well, given that the intent is to communicate, using GWh is probably ideal. 10.7 million GWh is probably the easiest to understand and compare, given that GWh is probably the most commonly used unit for this purpose.

Re: Satellite powered estimation of global solar potential

#102

Post by treyd »

barbegal wrote: post #80

An interesting use for satellite in future will be accurate estimation of solar power output in the very near future e.g. in the next hour period such that grid operators can adjust storage and demand to get a balanced grid. At the moment we can't do these predictions as we don't know where solar panels are in relation to any passing clouds.

I'm sure you could get that data from public permitting filings. And failing that, train an AI model on scraped Google Maps imagery. I would be surprised if people aren't doing it already.

Re: Satellite powered estimation of global solar potential

#103

Post by sneak »

ben_w wrote: post #49
akira2501 wrote: post #32

Earlier quoted context omitted.

> This brings back memories of the time I almost shortened "thousand kilometres" to "kkm". SI is such a senseless system. Unit prefixes were not a good idea. Did you move the decimal point or just switch to "Mm?"

In that specific case, I chose megameters.

At which point even metric-users who think in km are confused.

Certain things are measured in certain units, prefix included.

This would be like writing interstellar distances in km instead of light years or parsecs.

Re: Satellite powered estimation of global solar potential

#104

Post by scotty79 »

tsycho wrote: post #93
mlsu wrote: post #92

This is fine and all, but each individual having a solar panel introduces a lot of issues. Your energy bill is about 1/4 or 1/3rd distribution. As you take less power from the grid because of the solar on your roof, that proportion grows larger and larger. At the same time, the power company makes less money off of you, because you are using less power. Therefore, they have less money to invest in distribution, which…

Valid points. Is there a known solution to this, even if it's too expensive today? Would it make sense for local electricity companies to go full solar with large battery backups? Or are batteries too expensive, or don't last long enough, for this to be feasible? What about a wind+solar combination? Both of them are unlikely to go offline at the same time. I see articles that the cost of wind and solar keep going dow…

The solution to that is as much distributed storage as possible and cryptocurrency mining (or LLMs) for monetizing excess energy.

Re: Satellite powered estimation of global solar potential

#105

Post by scotty79 »

ccozan wrote: post #60
stainablesteel wrote: post #52

Earlier quoted context omitted.

i've heard of some business models that install these and have you pay what would be the difference to your electric bill to the company until they pay themselves off, not sure if the panels last long enough to make that work though

Yes. In Germany they are selling a lot of models, but none, I mean, really, none asked about the rentability. So I went to a neighbour who just installed his 25kW and was very proud and happy, and asked him, in how many years is the return of investment. Siderated, he could not answer and then a few days later, with a very stern face: 25 years or more because if more people install these, the price that the city is p…

What if he added previous generation crypto miner (so it's cheap) and use the excess electricity instead of selling it to the grid? This could also save some money on heating in winter unless he has a heat pump priced in already.

Re: Satellite powered estimation of global solar potential

#106

Post by PaulDavisThe1st »

scotty79 wrote: post #105
ccozan wrote: post #60

Earlier quoted context omitted.

Yes. In Germany they are selling a lot of models, but none, I mean, really, none asked about the rentability. So I went to a neighbour who just installed his 25kW and was very proud and happy, and asked him, in how many years is the return of investment. Siderated, he could not answer and then a few days later, with a very stern face: 25 years or more because if more people install these, the price that the city is p…

What if he added previous generation crypto miner (so it's cheap) and use the excess electricity instead of selling it to the grid? This could also save some money on heating in winter unless he has a heat pump priced in already.

prev gen crypto mining is phenomenally inefficient in terms of energy that ends up being converted to heat, but it is absolutely not what you would use to take electricity and create heat given any other choices.

Re: Satellite powered estimation of global solar potential

#107

Post by PaulDavisThe1st »

malfist wrote: post #89
NavinF wrote: post #74

Earlier quoted context omitted.

> Interlinking local capacity Is this a thing IRL? Every system I've looked at stops feeding the grid as soon as the grid goes down

There's a program involving F150 lighting trucks out in CA that pay you to grid tie them, that way a couple of them in your neighborhood can power the neighborhood for a day or so if wildfires take out the local grid

Anything grid tied is generally required to have phenomenally reliable shutdown if the grid goes down OR proven (and very expensive) automated switching that disconnects it from the grid if the grid goes down.

This is so those F150s are not backfeeding the wires while a repair crew is trying to fix it.

Ergo, if the local grid is "taken out", those F150s cannot be "on the local grid".

Re: Satellite powered estimation of global solar potential

#108

Post by PaulDavisThe1st »

xbmcuser wrote: post #99
wongarsu wrote: post #76

Earlier quoted context omitted.

They have to. Feeding your own home needs some setup but is fine. But electricity companies require you to disconnect generating capacity from the grid when the grid is down to make it easier to effect repairs. But that's more a policy decision than a technical restriction. We could change it so power can flow on both sides of a fault instead of only the "upstream" grid side.

With battery systems getting so cheap maybe community batteries will become a thing where a neighborhood exports it's solar too and is it's own small grid.

that would mean either:

a) government mandates that turn over existing grid infrastructure to such a project, because the existing grid infrastructure is almost all privately owned

OR

b) building new infrastructure to create an isolatable local grid

Neither of these seem particularly likely to me.

Re: Satellite powered estimation of global solar potential

#109

Post by PaulDavisThe1st »

yen223 wrote: post #28
xnx wrote: post #12

This is a very impressive refinement of their existing tool, but is this type of advanced calculation of roof-pitch (etc.) still relevant? Haven't we more or less concluded that a million piecemeal rooftop installations of solar are about the worst way to do it? More complicated and expensive to permit and install, less efficient operation, difficult to repair, difficult to insure, difficult to upgrade, inefficient t…

With rooftop solar there's a path towards mass deployment that other alternative electricity generation solutions currently lack. Rooftop solar for residential houses doesn't require permits or planning, and can be done by individuals within a reasonable budget, unlike solar farms or rooftop nuclear.

> Rooftop solar for residential houses doesn't require permits or planning

Either you're assuming residential battery storage systems replacing the grid, or your ignoring the connecting rooftop solar to the grid requires permits and planning (the grid may not be able to handle it).

Re: Satellite powered estimation of global solar potential

#110

Post by bruce511 »

rrr_oh_man wrote: post #96
pyaamb wrote: post #70

This is really incredible. If they could plug in local utility prices and come up with estimate for dollars saved per year, that would be an incredible conversation starter for homeowners who might not have considered taking on a home solar project otherwise.

> incredible conversation starter for homeowners who might not have considered taking on a home solar project otherwise Once you do the math in a Northern country (sans subsidies) it's not as compelling as you might think.

By "Northen" I assume you mean Europe, and (most of) USA?

I live near the 33rd parallel South. Since installing solar my annual grid requirements are around 30% of before solar [1] ‐ even as my actual consumption has risen [2].

As far as "Northern" goes countries in my latitude north (or better) include India, Mexica, all of Africa, most of China, and so on. So for most people living in the north it is compelling [4].

[1] a very large fraction of my grid usage is really cold, wet conditions for 6 weeks in winter. A combination of low generation and high usage for heating.

[2] cooling in summer is free, so we run the aircon a lot more. Plus things like slow-cooking etc are free as well.

[4] my return on investment (grid cost of generated electricity over capital invested) is 16.7%. Projected lifespan is 10 years for battery and inverter, 25 years on panels, 50 years on wiring.

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