Buildings account for around 40% of total energy consumption, and consequently around 40% of carbon emissions. So as we strive to reduce our carbon emissions you would expect ‘net zero energy buildings’ (Net ZEB) to offer a significant step in reaching our objectives. Unfortunately, things are not as simple as that. Net ZEBs alone do not have the level of impact their names suggest and a world full of Net ZEBs is impractical without significant modernization of the grid. A Net ZEB is defined as “a grid connected building that generates as much energy as it uses over a year,” according to a study by Jaume Salom of the Catalonian Institute of Energy Research and collaborators from around the world. “Net ZEBs do not exist in isolation”, the report points out, which perhaps counter-intuitively continues, “the wording ‘net zero’ implies an interaction with the grid.” Net ZEBs commonly still obtain approximately half their energy from […]