backup power

[genericname1]

Is there anyway to read accumulator capacity?

I'm running solar + accumulators but I'd like to be able to enable my old steam power station if the accumulators were nearly empty.

Now we can read the levels of storage tanks I can just about think of a way to detect if the power has gone off by pumping water between tanks but
1) It seems horribly inefficient
2) I'd really rather be able to enable the steam power station before the accumulators are completely empty (if I could enable at 20% remaining I'd need a much smaller plant to provide the extra boost to last until morning)

[ratchetfreak]

not without mods.

it's planned in 0.13 though (or maybe a minor update depending on how difficult adding it is)

[Tallinu]

You'll probably have to use something like the old power sensor trick using accumulators bridging two power networks. Pumping fluids between tanks sounds a lot like the old trick of using one inserter to keep a chest empty or not empty while another tries to do the opposite, with the items (typically fuel) circling between them on a belt, and in some builds, reading the contents of that chest for a signal that power is low (when one of the inserters slows down or stops because the small network it's on can't get enough power through the accumulator bridge anymore).

I've also heard of tricks like pumping water out of a pipe before it reaches boilers or steam engines. But you can now control small pumps and offshore pumps via signals as well, so you can turn the flow of cold or hot water on or off at will much more easily than before, where you had to have a steam engine running on an independent boiler which would become fueled if the inserter stealing the incoming fuel and putting it back in that chest stopped running fast enough to keep up with the one taking it out.

If you store hot water in tanks you can quickly activate a number of steam engines to draw on that tank (which would be subsequently refilled by at least 14 boilers, to successfully heat all the water flowing through the pipe) based on a signal controlling the pumping of water from that tank to the steam engines. Steam engine activity would oscillate as the power is restored, causing the triggering chest to refill with items, causing the pumps to shut off, leaving the sensor system without power, causing the chest to empty out, causing the pumps to activate the steam engines once more, and so on until full power is restored (assuming your steam engines don't provide 100% of your base's power needs, or are somehow hooked up in such a way that they can't run the sensor indefinitely). And if you have trouble with the pumps not actually running due to the power crashing too fast, you can skip the hot water tank and just control the offshore pump feeding the backup power system's boilers instead, since neither of those require power to run.

People will probably discover more tricks with the new capabilities as they get a chance to play with them more. It'll definitely be interesting to see what refinements can be made now.