I was thinking, in particular, of grid battery power. Even if the battery is 'dated' it's still useful, and it can just sit and do it's job. As long as it is co

I was thinking, in particular, of grid battery power. Even if the battery is 'dated' it's still useful, and it can just sit and do it's job. As long as it is cost-efficient when it is installed, it makes sense to install it.