In an effort to promote sustainability and lessen the environmental impact of the campus, UNM has been reducing the campus energy usage through monitoring and retrofitting cooling, heating, water, and lighting technologies. Due to these efforts, the University of New Mexico's grade on the College Sustainability Report Card 2009 improved from a "C" to a "B" according to the Sustainable Endowments Institute. Since 2008, following an executive order that all new state buildings over need to meet LEED silver at minimum, all new construction on campus has been registered for LEED status. So far, an expansion of Castetter Hall and the Technology and Education Center are the only LEED-certified buildings on campus, with a Gold and Platinum rating respectively. Several other buildings are currently registered for LEED status.