After setting up my power system automation, I noticed I was wasting power with empty batteries, and a couple upstream parts of my circuit were reporting massive power draw, several times the total possible draw. After consulting the internet, I was clued into transformer bugs in previous updates, and sure enough, removing the transformers removed the wasted power and ghost power draw. Unfortunately my automation for sensing power levels cannot work properly without transformers
I'm not sure how to replicate the bug, but hopefully the bug is preserved in my world save. I do suspect it has some interaction with building multiple transformers in series.