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Satellite powered estimation of global solar potential

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Re: Satellite powered estimation of global solar potential

#51

Post by PittleyDunkin »

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…

> This brings back memories of the time I almost shortened "thousand kilometres" to "kkm".

For the uninitiated, what's confusing about this? It seems to communicate the intended meaning accurately. Is there some ambiguity here I missed?

Re: Satellite powered estimation of global solar potential

#52

Post by stainablesteel »

buckle8017 wrote: post #50

Estimate for a house in SF with a typical roof and typical electric bill. $20k upfront cost. $4k in savings over 20 years. That's an implied rate of return of 0.9% annually. No thanks.

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

Re: Satellite powered estimation of global solar potential

#53

Post by edent »

janitorHenry wrote: post #4

Builders: optimize energy capture, put roof planes directed south (in northern hemisphere).

That isn't quite true.

Electricity use is more common in the evening, so west facing panels do really well because they offset demand.

We have an East/West split on our panels and they're excellent for providing instantly useful electricity as opposed to stored electricity.

Re: Satellite powered estimation of global solar potential

#54

Post by xattt »

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…

Why not both?

Re: Satellite powered estimation of global solar potential

#55

Post by elliottkember »

PittleyDunkin wrote: post #51
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…

> This brings back memories of the time I almost shortened "thousand kilometres" to "kkm". For the uninitiated, what's confusing about this? It seems to communicate the intended meaning accurately. Is there some ambiguity here I missed?

I think it's that a thousand terawatts is equivalent to one petawat. So this is 10.7PWh.

Re: Satellite powered estimation of global solar potential

#56

Post by vermilingua »

ant6n wrote: post #33
Veserv wrote: post #24

Earlier quoted context omitted.

SI prefix words are just kind of silly. We should just use the exponent as a number instead of having a different word for every 3 zeros. 10.7 E15 Wh or something similar. Scales to everything, you do not need to know any mapping, and directly supports mathematical manipulation. We should also do the same for large number words in general. No thousand, million, billion, etc. E3, E6, E9, etc. Now you can count and rep…

You mean 1.07E16

It's pretty common in some contexts to only use Es for powers of 1000, so 100,000,000 is 100e6 rather than 1e8.

Re: Satellite powered estimation of global solar potential

#57

Post by [deleted] »

XorNot wrote: post #44
ijustlovemath wrote: post #37

Earlier quoted context omitted.

As someone who recently lost power and water for weeks post Helene, do not discount the power of distributed grids. Distributed core infrastructure will make for much better climate resilience. Don't miss this in your efficiency calculations.

Grid connected solar goes down when the grid is out though. You need specific inverters to retain power. You also just have issues like the low chance of having clear skies after a hurricane or a bushfire. For disaster situation power, a diesel generator is still the cheapest and most reliable option.

[deleted]

Re: Satellite powered estimation of global solar potential

#58

Post by PittleyDunkin »

elliottkember wrote: post #55
PittleyDunkin wrote: post #51

Earlier quoted context omitted.

> This brings back memories of the time I almost shortened "thousand kilometres" to "kkm". For the uninitiated, what's confusing about this? It seems to communicate the intended meaning accurately. Is there some ambiguity here I missed?

I think it's that a thousand terawatts is equivalent to one petawat. So this is 10.7PWh.

Ah so the complaint is of moving the last order of magnitude onto the quantity rather than the unit. I can't imagine this affects readability that much (although I can understand why you'd want to enforce consistency in an academic context).

Sometimes it's useful to distinguish these, though. And after many do have the inexplicable "MM" suffix (ie s thousand-thousand) to suffer through which seems much worse.

Re: Satellite powered estimation of global solar potential

#59

Post by Glyptodon »

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…

At a certain point shouldn't things get good enough you don't really need a traditional power grid?

Re: Satellite powered estimation of global solar potential

#60

Post by ccozan »

stainablesteel wrote: post #52
buckle8017 wrote: post #50

Estimate for a house in SF with a typical roof and typical electric bill. $20k upfront cost. $4k in savings over 20 years. That's an implied rate of return of 0.9% annually. No thanks.

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 paying for the pumped energy goes down.

So no. 20kw is not the answer. I showed my setup: 3.5kw + big battery. Pays the bill approx 60 70% of the daily usage. Investment payback : 5years.

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