The logo could use recognizable shapes/energy symbols that combine into other meaningful shapes/energy symbols. Our favorite logos from the logo store are:
(1) Energy Solutions (by KitDesignStudio) - with the light bulb/arrows/plant - but we think it should look more web 2.0ish with a darker green color throughout, and a less-generic-looking plant in the bulb section.
(2) Home Energy (by appletart) - with the house/thermometer/roots coming out of the bottom - this one is very cool and professional looking.
(3) nametreehouse (by deda) - with the tree and house built into the branches - the tree with the house built into the branches is good use of multi-meaning symbolism. Maybe this kind of plant could be used as the centerpiece to take the place of plant in the Energy Solutions Logo while also making the green more pronounced and working toward an overall more web 2.0 look.
Other logos from the 99Designs Logo Store that we like are:
Energy Green (by ledevil)
Alternative Energy (by inasor)
eco friendly energy (SCR Enterprise)
Green House Logo (by artmart)
In general, these descriptions are hopefully supposed to assist the artists with your own unique logo design. Thanks again for your creative efforts!