Number of accumulators required to power factory?

[Zeblote]

I've found a topic about accumulator / solar panel ratios ( https://forums.factorio.com/forum/vie ... f=5&t=5594 ) but nothing telling me how many of them I actually need.

I guess you could calculate it, but for that you'd need to know the max power the factory can draw with everything running, and there doesn't seem to be an option to see that

Do people just guess the ammount until it works?

[DaveMcW]

Multiply your average power consumption by 100. That's how much accumulator capacity you need if you're following the 0.84 accumulator/solar panel ratio.

[Zeblote]

I'll try that, where does the 100 come from though?

[DaveMcW]

100 seconds of darkness per day. https://forums.factorio.com/forum/vie ... 254#p43254

[Koub]

One solar panel is able to output 42 kW overall when you consider the day and night cycle (60 kW during day, 0 during night, and linear ptogression from 0 to 60kW and 60kW to 0 during dawn and dusk).
The correct ratio if your factory uses around the same power whether it's day or night is 0.84 accumulator panels for each solar panel (or 84 accus for 100 solar panels).

As long as the day/night cycle doesn't change, you don't have to know its length to use these numbers : each solar has an average maximum output of 42 kW, and for each 100 panels, you need 84 accus. If you're short on power, recalculate your average consumption, and add the solar/accus needed to match.