Paul Torcellini, principal engineer with the U.S. Department of Energy’s National Renewable Energy Laboratory, discusses how we can achieve zero-energy buildings by integrating the cost of energy efficiency into design decisions. This is the first presentation captured from Ecobuilding Review’s 2014 Vision 2020 Sustainability Summit. The original article can be viewed here. For more information on the year-long Vision 2020 project, which aims to establish and track a roadmap of cr...