[HN Gopher] Satellite powered estimation of global solar potential
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Satellite powered estimation of global solar potential
Author : jonbaer
Score : 101 points
Date : 2024-12-19 20:44 UTC (2 hours ago)
(HTM) web link (research.google)
(TXT) w3m dump (research.google)
| HocusLocus wrote:
| "We lose a little on each transaction, but make up for it in
| volume."
| janitorHenry wrote:
| Builders: optimize energy capture, put roof planes directed south
| (in northern hemisphere).
| elric wrote:
| 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.
| cjbgkagh wrote:
| 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.
| jcgrillo wrote:
| 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.
| elric wrote:
| Not every roof allows for perfect southward angling
| (obviously).
|
| And I'm obviously not saying that you should point panels
| north either. I'm disputing the parent commenter's claim
| that it would be beneficial to have all panels aimed
| directly due south. Because that way you get one strong
| peak at noon, which is the time of day when solar energy is
| most abundant but also least used.
| toast0 wrote:
| Pointing west is a reasonable option in California.
| Pointing west reduces production, but also shifts it later
| in the day, and addresses some of the duck curve.
| szvsw wrote:
| There's not always a lot of freedom to control roof angles like
| that - it might eg be directly determined by the orientation of
| the street - and even if there is, it might come into conflict
| with other thermal considerations. For instance, perhaps
| orienting the building such that the roof midline is E/W and
| the surface is due south results in more windows pointed due
| south, which in turn drives much more solar gain on the
| interior and greater cooling loads as a result - maybe the
| increased solar output outweighs those gains, maybe it doesn't.
| You have to run some thermal sims to check. On the other hand,
| you will have more solar gains in the winter, which will
| decrease your heating demand.
|
| So it's not universally applicable - but it is absolutely true
| that it will increase solar output!
| ben_w wrote:
| 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 being historically exponential and
| asking why they don't assume the exponent will continue -- I'm
| expecting about double their number for PV by 2035, if trends
| continue.
| jjcm wrote:
| > 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.
| geepytee wrote:
| The correct solution is 10.7Pwh. We are often exposed to
| 'Peta' when dealing with data.
|
| https://en.wikipedia.org/wiki/Metric_prefix
| jeffbee wrote:
| EIA Electricity Monthly gives data in certain tables in terms
| of either million kWh or "thousand megawatthours" which isn't
| even English. Let's just use J.
| psychoslave wrote:
| 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
|
| - 10.7x103
|
| - 1.07x104
|
| - 10.7e3
|
| - 1.07e4
|
| - 29E816
| Veserv wrote:
| 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 represent any meaningful number without needing
| to memorize a dictionary of words and they would precisely
| match the unit scale "words".
| ant6n wrote:
| You mean 1.07E16
| mjan22640 wrote:
| Joules is the solution to both the problems (the second is
| that Wh for energy is as silly as speed hours for distance)
| rcMgD2BwE72F wrote:
| >despite at least a decade of people pointing at it being
| historically exponential and asking they don't assume the
| exponent will continue.
|
| So crazy and true. Sources:
|
| https://www.economist.com/interactive/essay/2024/06/20/solar...
|
| https://www.exponentialview.co/p/the-forecasters-gap
|
| 7 years ago (!): https://xwpxpfefwalgifkr.quora.com/A-modest-
| proposal-to-the-...
| Retric wrote:
| Both linear and using the current exponent are likely to be
| wildly off.
|
| If you assume it's ~26% annual growth now, and drops by 2% per
| year so 24% next year then in 10 years you'll see 4.25x last
| years installs and the cumulative initiation over the next
| decade is 2.8x a linear estimate.
|
| IMO that's probably a reasonable ballpark, though capacity
| factors are an open question as they could fall dramatically or
| maintain fairly steady depending on how much grid storage shows
| up.
| akira2501 wrote:
| > 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?"
| jeffbee wrote:
| 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" everywhere.
| josh-sematic wrote:
| 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.
| jeffbee wrote:
| 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).
| mbreese wrote:
| 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.
| josh-sematic wrote:
| There are several allocation opportunities I could think
| of. You're a local government considering some subsidies
| for rooftop solar initiatives. How much bang for your buck
| will you get? You're a regional grid operator and have some
| estimates for rooftop solar adoption. How do you translate
| that into plans for future grid capacity needs? You're a
| rooftop solar installation company. What neighborhoods do
| you send your mailers to?
| akira2501 wrote:
| Perhaps those three different groups should just
| coordinate together, rather than individually using this
| data, and arriving at three different and possibly
| interfering conclusions.
|
| Aside from that grid operators buy power from producers.
| They don't plan future capacity more than 72 hours in
| advance. If you're a producer with expensive power you
| won't sell much. If you're a producer with cheap power
| you will sell a lot. It's already a functioning market.
| Solar is a very small part of it.
| xnx wrote:
| 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.
| dvh wrote:
| I'll take 3kW on my rooftop over 5kW in billionaire's company.
| szvsw wrote:
| One advantage of distributed solar is that it can at least come
| online right away and when installed with a battery, can get a
| home pretty close to being fully self-sufficient (depending on
| the climate/heating system), whereas the generally much more
| efficient solar pv power facilities have to contend with
| backlogs in connecting to the grid, insufficient grid capacity,
| etc.
|
| But yes, distributed solar will not be the general solution to
| decarbonizing our energy systems as a whole. Does serve a
| meaningful role though and there is no reason to not do both.
| CorrectHorseBat wrote:
| Insufficient grid capacity can also be local, there are many
| cases of inverters turning off because of too high grid
| voltage in the Netherlands
| throwaway346434 wrote:
| Or to put it another way: available with a rate of return that
| makes it sensible for average middle class home owners to say
| yes to, to the point dirty power sources are having to shut
| down in some markets (or fiercely lobby through the political
| system to be propped up).
|
| One such example:
| https://www.theguardian.com/environment/article/2024/sep/08/...
|
| Perfect is the enemy of good
| tejtm wrote:
| I thought we may have concluded that shareholder efficient
| centralized single point of failure systems are the least
| robust providers of basic human needs in the face of natural
| levels of uncertainty.
| yen223 wrote:
| 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.
| akira2501 wrote:
| > More complicated and expensive
|
| More durable for individuals in the face of large scale
| failures. You're paying for something real there.
| ijustlovemath wrote:
| 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.
| srameshc wrote:
| There was a startup that was doing something similar, can't find
| it but their entire business was built on providing similar
| service.
| larodi wrote:
| hundreds of people do this at the moment worldwide, no surprise
| someone is productivising it, or many people are.
| MaxDPS wrote:
| I applied at a company called WattTime a few years ago. I
| didn't get the job but their work involved some of that. It
| sounded really interesting.
|
| https://watttime.org/about-us/climate-trace/
| ximeng wrote:
| https://www.transitionzero.org/products/solar-asset-mapper
| perhaps
| bangaloredud wrote:
| Ah yes solar, the great improver of landscapes - just like those
| composite bird shredders.
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