I've been leaving comments on each design, and will continue to do so.
General observations so far: a lot of very masculine designs with very blocky fonts. I'd like to see some varied fonts, and would encourage people to think "nature, local" as much as possible. We are an energy company, but we are relatively tiny, and there is an element of cottage industry to what we do. I know that a concept like "local" is very difficult to convey, but you are the experts, so impress me.
If you have wacky ideas, try them out.
If anyone is interested in seeing what we have been using, a low-fi version is here:
http://ybiofuels.org/images/circlelogoforLT.jpgAlso, if you want to get a feel for us as a company, you may want to hang out at our website a little bit:
http://www.ybiofuels.org