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> You see this quite a lot. There does come a point where adding more solar … when a certain percentage of your production is already solar … there comes a poin

> You see this quite a lot. There does come a point where adding more solar … when a certain percentage of your production is already solar … there comes a point where more solar is a whole lot more expensive and less reasonable. 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. [1] https://wiki.factorio.com/Solar_panel https://wiki.factorio.com/Solar_panel

jnsaff2 5y ago
Let me get this right. 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.
- mjevans 5y ago
  It's game-ified and an alien planet. Could be a tool to learn how to think of the problem. 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 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.

jnsaff2 5y ago

Let me get this right. 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.

mjevans 5y ago
It's game-ified and an alien planet. Could be a tool to learn how to think of the problem. 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 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.