I looked in to those, but for those to be effective you need to keep them always charged. Also cheaper ones need air conditioned space and more expencive ones were, well expensive.

I also need three-phase power for some tools away from the home and the convertor for the batteries seemed really expensive and not easy to use on the fly.

And biggest thing is that if something reallu bad happens i can easily get more gas, but recharging batteries would mean i need to go somewhere to charge them.

Another thing that somebody is going to say soon are solarpanels, but i live near arctic circle and during winter the operating time for them is so short i would need to make way too big solar farm for them to be usefull.