this is a lesson factorio can teach us. from[1]:
"A single solar panel outputs an average of 42 kW over a day and requires 0.84 accumulators to sustain a constant power output through the night.
It takes 23.8 solar panels to operate 1 MW of factory and charge 20 accumulators to sustain that 1 MW through the night."
the rules are contrived and simplistic, but the principles apply. the effectiveness of solar generation varies relative to net consumption rate and storage capacity. of course, some inefficiency may be desirable to avoid severe weather problems, but our imprecise climatalogical models dont positively affirm a sense of impending doom. hard to tell what the correct path is.
You are using numbers from a computer game wiki in a discussion about real world?
Numbers which are by the way off by 2 orders of magnitude. Don't have any nuance in them, don't account for any seasonal variance nor in fact for weather.
Quick ballpark numbers. Common solar panels are between 15 and 20% efficient. Numbers for the _surface_ of the earth (not the upper atmosphere) are quoted as about 1000W per square meter in a search. I assume that's a peak number.
Since I don't want to think about weather, calculus, or any other factors for a napkin estimate, can we agree that's 8 hours of useful output at 1KW of input power per hour? So over a day 1 meter of solar panel would generate between 1.2 and 1.6 KW / day? I'd also very crudely extend that to 75% of the daily output must exist as a storage buffer. (Gut feeling more than anything else.)
1.2KWd to 1.6KWd of daily generation per square meter.
0.9KW to 1.2KW storage; per square meter for a day.
I have trouble visualizing that though. https://en.wikipedia.org/wiki/Deep-cycle_battery Suggests that the discharge should only be to 50% on a regular basis for the most economy of material use (and thus cost). Double the above estimates for the storage bank.
Searching for "deep cycle battery solar" I see many results for 12V 110AH batteries, just a tiny bit more than the 1200KW storage value I guestimated earlier. Around 200 dollars per battery, about 13 x 7 x 8.5 inches (rounded up). So a big honking consumer 'truck' / SUV battery sized deep cycle battery, but double that up for wear prevention.
Though I still prefer baseload generation capacity for industrial and 24/7 loads. Solar can be a good peaker for AC use and waking consumer stuff.
https://www.eia.gov/electricity/monthly/epm_table_grapher.ph...
Presumably you want a lot of hydroelectric, wind, and nuclear so you don't need a lot of batteries, and you have enough sources of power when the sun isn't shining.
Maybe I'm being un-imaginative - but is anyone envisioning a global energy grid so we could have solar energy from Australia and Sahara shipped to North America during our night - and back to Asia and Europe from the Southwest during our day??
^ This seems nonsense science fiction.
Even now peak demand and peak solar production are fairly close daily.
We’re going to enter an energy economy where production isn’t just instantaneously controlled but supply is going to be a bit more dynamic and pricing is going to reflect that. There have already been demonstrated markets where this has been efficiently handled.
For a while there will be things like occasional negative pricing, but once users figure out how to take advantage of this prices normalize and usage will better match capacity patterns and new power installations will match new demand patterns.
Intuition on what you guess will be the case is a bad way to make arguments about infrastructure. Go look up actual data.
[1] https://reneweconomy.com.au/south-australia-makes-big-leap-t...
South Australia does not have cheaper electricity bills. We also had a multi-day outage in 2016 which was partially due to wind generators shedding load. Large scale solar also periodically turn off rather than pay to add power to the grid due to too much installed capacity and no suitable storage.
This is more of a failure of development and regulation of standards, which, I believe, have now been resolved. Said standards had already been developed in countries that had more experience in wind generation than Australia.
The "cause" was unprecedented wind speeds that brought down a few of the big "giraffes" that carry high voltage wires across the state and the interconnectors between states. See article below for example photo.
https://www.abc.net.au/news/2021-09-28/sa-statewide-blackout...
A lot of good has actually come out of that event, none related to the politicking.
More info: https://en.wikipedia.org/wiki/2016_South_Australian_blackout
[1] https://www.pv-magazine-australia.com/2021/09/30/nsw-gives-a...
I rescind my statement from my higher level comment that "They have the lowest energy costs in Australia"; the data is incomplete, there are multiple factors at play between generators, transmission, and retail supplier cost variations, and it was too broad of a statement considering all of the factors involved (when I should've referred specifically to wholesale rates influenced by renewables).
[1] https://www.premier.sa.gov.au/news/media-releases/news/bang-...
[2] https://indaily.com.au/news/business/2021/05/10/rise-of-sa-r...
Depends on how much storage you have. There is very, very little right now so even 50% might be a stretch.
> Maybe I'm being un-imaginative - but is anyone envisioning a global energy grid so we could have solar energy from Australia and Sahara shipped to North America during our night - and back to Asia and Europe from the Southwest during our day??
I'd think you'd need a relatively inexpensive superconducting cable for that to make any sense. Running cables between continents has been a thing for over 150 years, but I'd think resistance losses would make it wildly impractical to power, say, Los Angeles with solar power collected in Australia.
Allow me to present to you the "Australia-Asia Power Link" [0], exporting solar power a distance of about 4,500km, which is still less than half of LA to Australia, but not insignificant.
What governs the practicality is often more complex than just power loss. Carbon credits, local taxation, and plain ol' bureaucracy can make it more profitable to export than to consume.
The cost for both is the big thing: even just assuming overnight electricity replacement, 12 hours * 2 TW * $100/kWh = $2.4 trillion; the 8 GW English Channel link cost $1.6/km[0][1], which a naive scaling up to 20 Mm and 2 TW would cost $8 trillion. Then the question is “which lasts longer, and which is harder to refurbish at end of life?”. (Numbers are just a guideline. On the one hand there is less demand at night and there will probably be wind and geothermal in the mix, on the other hand we want something that allows everyone to have an energy use currently only available to rich people and this doesn’t cover anything except mere electricity).
I have not been able to find the size of the global energy industry in dollars per year to compare this to, only an un-cited claim of “$5 trillion per year … subsidizing the fossil fuel industries”.
That said, at this scale I have to ask about the economics of making an orbital ring, transferring power kinetically in what is essentially a ballistic superconductor[2], and now you can put the PV in space on the ring without having to solve the political aspects of “can I convince everyone else I’ve not sneakily designed my power satellite to be used as a death ray, and can I be sure everyone else’s can’t all be told to collectively focus on one place even if I trust the owners’ intentions?” that usually follows any discussion of space-based solar.
[0] https://en.wikipedia.org/wiki/High-voltage_direct_current#Co...
[1] I’m ignoring converter stations because over 1 Mm they amortise to negligible
[2] i.e. purely classical and without the fun quantum magnetic effects: https://en.wikipedia.org/wiki/Ballistic_conduction
It's at the same point solar/wind were a few years ago when they were the cheapest form of energy but received a lot of criticism for making up a small % of total production.
Naturally that changed.
But that’s really more of a “80% of our power is solar” problem and the US isn’t even at 3%. The percentage of usage which could be handled by solar is usually far underestimated.
We don’t need to care about limitations of solar for a long long time.