Alteris Renewables, a Real Goods Solar company, is the largest design-build renewable energy company in the Northeast, with m ... ore than 30 MW installed for over 4,000 customers over the past thirty years and more than a dozen offices across six states. Ranked as one of the top ten fastest growing energy companies in the Inc. 500, Alteris provides turn-key solar electric (photovoltaic or PV), solar thermal, and wind energy solutions for commercial, residential, education, government and institutional clients. The company has industry-leading expertise in engineering, design, project management, performance analysis, project financing and renewable energy credit programs. read more