Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Satellite powered estimation of global solar potential

research.google

Post reply on HN
Print view View original

11–20 of 216 posts

Re: Satellite powered estimation of global solar potential

#11

Post by josh-sematic »

jeffbee wrote: post #6

The image processing described is very cool, but I have questions about the application. Google started doing these solar potential estimates about 10 years ago, so let's imagine that they have been developing the capability since about 2010 or so. In that time the cost of PV has fallen by an order of magnitude. Hasn't that settled the question of where PV should be installed? I thought the answer is now "yes" everyw…

Even assuming 100% solar rooftop coverage is the goal, given limited capacity of raw materials, labor, infrastructure would still necessitate prioritization of when to allocate those things to which places.

Re: Satellite powered estimation of global solar potential

#12

Post by xnx »

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 to integrate into grid, etc.

Re: Satellite powered estimation of global solar potential

#13

Post by jeffbee »

josh-sematic wrote: post #11
jeffbee wrote: post #6

The image processing described is very cool, but I have questions about the application. Google started doing these solar potential estimates about 10 years ago, so let's imagine that they have been developing the capability since about 2010 or so. In that time the cost of PV has fallen by an order of magnitude. Hasn't that settled the question of where PV should be installed? I thought the answer is now "yes" everyw…

Even assuming 100% solar rooftop coverage is the goal, given limited capacity of raw materials, labor, infrastructure would still necessitate prioritization of when to allocate those things to which places.

But the audience isn't an omnipotent controller of PV panel allocation, it's emergent market participants. Presumably, the market emerges more plentifully in those sunnier places. It's hard to imagine the place where this data is useful to local construction firms who were previously not well-informed (potentially by just walking around with their eyes open).

Re: Satellite powered estimation of global solar potential

#14

Post by elric »

janitorHenry wrote: post #4

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

That's terrible advice unless it's tied to local energy storage.

When every roof and every solar panel is angled the same way, a sudden cloud (or a sudden lack of clouds) can cause huge fluctuations in power output. Diversity is protective.

Re: Satellite powered estimation of global solar potential

#16

Post by mbreese »

jeffbee wrote: post #13
josh-sematic wrote: post #11

Earlier quoted context omitted.

Even assuming 100% solar rooftop coverage is the goal, given limited capacity of raw materials, labor, infrastructure would still necessitate prioritization of when to allocate those things to which places.

But the audience isn't an omnipotent controller of PV panel allocation, it's emergent market participants. Presumably, the market emerges more plentifully in those sunnier places. It's hard to imagine the place where this data is useful to local construction firms who were previously not well-informed (potentially by just walking around with their eyes open).

Maybe it's useful when trying to justify solar adoption. If you have control over some level of panel allocation, you could use something like this to explore where you'd want to put panels first -- answering the question of where are you going to make the best economic case for solar panels.

Then, once the top places are addressed, you can move onto the second tier of locations, then the third, etc...

This could be helpful if you're in gov't and have some control over a pilot neighborhood project. Or a developer that wants to include solar on some homes/businesses and wants to know where it makes the most sense.

You're right that this probably isn't too much better than qualitative reasoning about how sunny certain places are, but this is quantitative, so you can have a little more confidence in your qualitative assessment.

Re: Satellite powered estimation of global solar potential

#17

Post by cjbgkagh »

elric wrote: post #14
janitorHenry wrote: post #4

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

That's terrible advice unless it's tied to local energy storage. When every roof and every solar panel is angled the same way, a sudden cloud (or a sudden lack of clouds) can cause huge fluctuations in power output. Diversity is protective.

Unless there is something I'm missing, the sun still shines from the same direction regardless of the cloud coverage so I'm not sure how having panels pointing in other directions could improve the matter. Perhaps there is a case for optimizing panel area for different times of day but since panels are so relatively cheap it seems the advice is just to get more panels than spend much time worrying about such things.

Re: Satellite powered estimation of global solar potential

#18

Post by psychoslave »

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.

I was reading https://en.wikipedia.org/wiki/International_System_of_Units and a few related the other day for fun and pleasing moment, and one thing I retained from that is that "The kilogram is the only coherent SI unit whose name and symbol include a prefix." Also that the standard explicitly forbid redundant use of prefixes like kilo-kilo-.

I guess that if you want to stick to TWh you can use

- 10700

- 10,700

- 10.7×10³

- 1.07×10⁴

- 10.7e3

- 1.07e4

- 29E8₁₆

Re: Satellite powered estimation of global solar potential

#19

Post by dvh »

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…

I'll take 3kW on my rooftop over 5kW in billionaire's company.

Re: Satellite powered estimation of global solar potential

#20

Post by jcgrillo »

elric wrote: post #14
janitorHenry wrote: post #4

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

That's terrible advice unless it's tied to local energy storage. When every roof and every solar panel is angled the same way, a sudden cloud (or a sudden lack of clouds) can cause huge fluctuations in power output. Diversity is protective.

Are you signing up to point your panels north and take a 30% efficiency hit? Or east/west for a 15% penalty? People point them south because it's the most efficient fixed orientation north of the equator. A more efficient solution is to use a tracker which keeps them pointing directly at the sun as it traverses the sky.
Post reply on HN