Investing in green tech a great way to get in on the ground floor of a burgeoning sector with global exposure, but you may be taking a gamble on still unproven technologies.

See which10 companies ranked on top.

The solar energy industry will grow faster than expected during the next few years as American utilities invest heavily in large-scale solar farms, analysts with Barclays Capital said in a research note.

Investors typically look to small cap stocks as the leaders out of a recession. More nimble than their large-cap counterparts, small cap companies are quicker to adapt during both economic downturns and periods of recovery.