I know nothing about electricity other than the fact that AC and DC are different, so feel free to mod this down.
Assuming that our DC sources of electricity are already somewhat efficient, why don't we just have other things that use that current be DC as well?
It would seem that inverters loose some "energy" in the conversion process, which is why we need this Google like X Prize to develop something more efficient...so taking them out of the equation seems like it would be a good idea.
Is it just that we're so used to designing electronics etc. to use AC, or are there other benefits? and, if so, then why not put effort into designing AC sources of electricity?