A Common
Definition for Zero Energy Buildings
Thousands of
project teams throughout the country seek to push the envelope and develop zero
energy buildings. A zero-energy building produces enough renewable energy to
meet its own annual energy consumption requirements, thereby reducing the use
of non-renewable energy in the building
sector. This definition also applies to campuses, portfolios, and communities.
"A
zero-energy building, also known as a zero net energy
(ZNE) building, net-zero energy building (NZEB), net-zero building or zero carbon building is a building with zero
net energy consumption. These buildings consequently contribute less overall
greenhouse gas to the atmosphere than similar buildings. They do at times
consume non-renewable energy and produce greenhouse gases, but at other times
reduce energy consumption and greenhouse gas production elsewhere by the same
amount. A similar concept approved and implemented by the European Union and
other agreeing countries is nearly zero energy building (nZEB), with the goal
of having all buildings in the region under nZEB standards by 2020.
Even though a
building with ‘nearly zero energy consumption’ has a higher initial cost, the
benefits of its construction are remarkable.
·
Not affected by a future increase in energy costs
·
Offer improved thermal comfort due to the
uniform internal building temperature
·
Have hardly any energy requirements, thus,
hardly any operational cost to cover the energy needs of the building
·
Enjoy reduced overall net monthly cost of
living and offer a higher quality of life
·
Offer Improved reliability – many technologies
for renewable energy resources and energy conservation have a long lifespan and
low maintenance cost
·
Have a higher resale value
·
Contribute to the protection of the environment
as nearly zero energy consumption means nearly zero emissions which cause the
greenhouse effect
·
Exemption of possible future legal
restrictions; from taxes on carbon dioxide emissions to mandatory energy
renovations which are costly
·
Helps significantly to improve the building’s
aesthetics
Any
building or construction characterized by ZNE consumption and zero carbon
emissions calculated over a period. Zero-energy buildings (ZEBs) usually use
less energy than traditional buildings as well as generate their own energy on site
to use in the building; hence, many are independent of the national (electricity) grid. ZEBs have emerged in response
to stringent environmental standards, both regulatory and voluntary, introduced
to address increasingly significant environmental issues such as climate
change, natural resource conservation, pollution, ecology, and population.
ZEBs need to
produce their own energy on site to meet their electricity and heating or
cooling needs. Various microgeneration technologies may be used to provide heat
and electricity to the building, including the following:
· Solar (solar
hot water, photovoltaics [PV]).
· Wind (wind
turbines).
· Biomass
(heaters and stoves, boilers, and community heating schemes).
· Combined heat
and power (CHP) and micro-CHP for use with natural gas, biomass, sewerage gas,
and other biogases.
· Community
heating (including utilizing waste heat from large-scale power generation).
· Heat pumps (air
source [ASHP] and ground source [GSHP] and geothermal heating systems).
· Water
(small-scale hydropower).
· Other
(including fuel cells using hydrogen generated from any of the above renewable
sources).
Sources
BTO (Building
Technologies Office) - https://www.energy.gov/eere/buildings/building-technologies-office
& https://www.energy.gov/eere/buildings/zero-energy-buildings
Internet
Article - http://www.geg.com.cy/the-companies/energy-and-beyond/zero-energy-home/
Zero-energy
building - https://en.wikipedia.org
(Encyclopedia
Britannica, 2012)
