I’m tired of buying a new 12 V battery every 1-2 years. I have about 4 small (rated ~ 300 W [not VA]) UPSes with 7 Ah, 12 V, maintenance free batteries.
I’m thinking about replacing them with one, powerful unit. But the more powerful the unit, the more it costs - non-linear.
Do you have experience with some DIY solutions? Like 12V DC to 230V AC inverter, battery charger, some UPS controller (simple relay?)?
Or maybe you have some other idea that is cheap(ish)?
Others have given the direct answer of “no”. Cheap is relative, so here are some options that assume a higher value of “cheap”.
DIY solar panels and DIY flywheel generator.
Professional solar panels on your dwelling and professional whole house battery storage. (Fix the issue by fixing a larger issue.)
Buy an electric car that can power the equipment. A Ford Lightning (there are other choices) in the garage, that never moves, will solve the issue of swapping batteries. Check junkyards for a used one.
Move closer to a power plant, while also ensuring a minimum power line distance.
Move closer to something with a very high up time requirement. (A hospital may have generators, but they may also have a requirement for their power to stay up nearly always.)
Use AWS or co-hosting to make power not your issue.
Are you really suggesting someone buy a used Ford Lightning to use as an alternative to a DIY UPS and never drive? The DIY UPS sounds 100x more practical.
No. I do not suggest anyone do any of these.