An aerial view of the net zero energy Exploratorium shows the extent of the solar photovoltaic system that sits atop the historic building and yet remains unnoticeable when viewed from the ground level. (Photo by Bruce Damonte)

An aerial view of the net zero energy Exploratorium shows the extent of the solar photovoltaic system that sits atop the historic building and yet remains unnoticeable when viewed from the ground level. (Photo by Bruce Damonte)

An aerial view of the net zero energy Exploratorium shows the extent of the solar photovoltaic system that sits atop the historic building and yet remains unnoticeable when viewed from the ground level. (Photo by Bruce Damonte)