Zero Energy Buildings
Source: US Department of Energy
The U.S. Department of Energy's Zero Energy Homes research initiative is
bringing a new concept to homebuilders across the United States. A Zero
Energy Home (ZEH) combines state-of-the-art, energy-efficient construction
and appliances with commercially available renewable energy systems such as
solar water heating and solar electricity. This combination can result in
net zero energy consumption. A ZEH, like most houses, is connected to the
utility grid, but can be designed and constructed to produce as much energy
as it consumes on an annual basis. With its reduced energy needs and
renewable energy systems, a ZEH can, over the course of a year, give back as
much energy to the utility as it takes.
Only about 10% of new homes in the United States are built significantly
above the minimum efficiency standards. Homes now use more total
nonrenewable energy than ever before. In fact, buildings currently consume
more than one third of all the energy and two thirds of all the electricity
used in the United States. New single-family homes are, on average, larger
than ever before, employ many more electrical devices, and 50% are being
built in the Sunbelt where the need for electricity is intense because of
summertime air-conditioning loads.
The Department of Energy (DOE) is sponsoring the Zero Energy Homes
initiative to capitalize on the expertise and technology that already exists
within DOE and its industry partners to dramatically reduce the amount of
energy consumed by single-family homes. The ZEH initiative seeks to build
more and more homes that perform at least 50% more efficiently than those
built to current minimum efficiency standards while also increasing the
number of new homes that can meet their own energy needs. The ultimate goal
of the ZEH initiative is to bring the benefits of zero energy technology
into the mainstream of both the residential and commercial building
industries, but the initiative's near-term focus is on new home
construction.
Zero Energy Homes have a number
of advantages:
Improved comfort—an energy-efficient building envelope reduces
temperature fluctuations.
Reliability—a ZEH can be designed to continue functioning even during
blackouts.
Security—a home that produces energy protects its owner from
fluctuations in energy prices.
Environmental sustainability—a ZEH saves energy and reduces pollution.
