Zero Energy Buildings
A net zero-energy building (ZEB) is a residential or commercial building with greatly reduced energy needs through efficiency gains such that the balance of energy needs can be supplied with renewable technologies. Despite the excitement over the phrase “zero energy,” we lack a common definition, or even a common understanding, of what it means. In this paper, we use a sample of current generation low-energy buildings to explore the concept of zero energy: what it means, why a clear and measurable definition is needed, and how we have progressed toward the ZEB goal.
There are a variety of different definitions for ZEBs around the world (and even within some regions/countries) that make it challenging to understand what is really being characterized as a ZEB, and the resulting progress toward dramatically reducing building energy consumption. There seems to be some harmonization happening as a few major economies, like the US, have developed standard definitions, though there seems to be a divide about whether “zero energy” or “zero carbon” is the better metric. Among advocacy groups there seems to be some consensus emerging that ZEBs are a means of making progress towards zero carbon homes and communities, though the majority of government policies have aimed toward ZEBs, and generally not yet focused on zero carbon buildings