Google has taken such an enthusiastic role in investing and promoting clean energy that, in terms of number of deals, the search engine giant was the second most-active cleantech venture investor during the third quarter. Google invested in five cleantech startups during the three-month period ended Sept. 30, according to a report from the Cleantech Group, including lithium-ion battery startup Actacell, geothermal company AltaRock Energy, electric vehicle makers Aptera Motors, high-altitude wind developer Makani Power, and geothermal company Potter Drilling. Still, we’re pretty sure Google is nowhere near the top when it comes to dollar amounts invested. For more details of the report and Google’s investment, visit Earth2Tech.