Jump-starting a car with a battery pack

I’m thinking about setting up a mining rig. Is there any actual way to save on electricity by running the machine off a battery bank? My idea is to charge the batteries at night when utility rates are bottomed out, then pull from those batteries during the day to avoid the peak pricing.

Basically, I’d hook up a charger to fill them up overnight while the power is half the price, then use an inverter to step that 12V up to standard household voltage to run the computer.

Will this actually result in savings, or am I just throwing money away because of the energy lost during the voltage conversion process? Is this a viable strategy, or should I just bite the bullet and invest in solar panels instead?

Right now, electricity costs are eating up about 15-30% of your margins, so there's really no point playing around with this. Plus, a massive battery—say, something like a 120Ah unit—isn't going to cut it if you're trying to run a single PC with a dedicated GPU for 14 hours straight every day.

wiredotter14 said:Right now, electricity costs are eating up about 15-30% of my margins. It’s just not worth messing around with. Besides, a standard large battery—say, 120Ah—isn't going to cut it if you're trying to run a single PC with a dedicated GPU for 14 hours straight.

I've already got two batteries set up. My main concern is the efficiency loss. If I'm converting from 120V to 12V and then back up to 120V again, is the power loss so significant that the off-peak rates won't even cover the difference?

How am I supposed to charge two 100Ah batteries on a charger within the 10-hour window of off-peak hours?

Even if you assume losses are only 50% of the difference between peak and off-peak rates—meaning a 25% gain, though it’s likely much worse—you might save a few bucks a day. But you'd need pro-level gear to make it work: high-quality batteries, a solid inverter, and a heavy-duty charger (over 20A), which isn't exactly something you want using to blast your batteries at those levels.