As climate change and environmental awareness rise to the forefront of the public consciousness, energy efficiency becomes a goal that many strive for in building design. For example, the 2021 International Energy Conservation Code, ANSI/ASHRAE/IES 90.1, or a combination of both have been adopted in most U.S. states. These two baseline energy codes set minimum energy efficiency requirements for buildings, an important factor in overall energy efficiency, as commercial and residential buildings account for nearly 40% of the energy consumed in the U.S.
In recent years, there has been a growing trend of constructing “net zero” or “zero energy” homes—homes that produce as much energy as they consume. While the net-zero concept is not new, interest in net-zero homes has surged in recent years as people become more aware of the benefits of sustainable construction. Here’s a look at what goes into creating these homes.
Reducing the Energy Consumed
The lower the energy needs of the home are, the less energy the home needs to produce. A net-zero home doesn’t necessarily have to be built with that goal in mind; plenty of homeowners can retrofit their homes to be more energy-efficient, and retrofitting an existing building can oftentimes be both more cost-effective and more environmentally friendly than constructing a new building for the purpose.
From triple-glazed windows to laboratory-tested Energy Star appliances, there are many ways to reduce a home’s energy requirements. Here are just a few:
- Green roofs are an incredibly effective insulator, as they are able to reduce the energy requirements for air conditioning by as much as 75%.
- Low-e glass in windows can reduce the energy loss by as much as 50%, and multi-pane windows provide even further insulation.
- Properly sealing and adding insulation to a home, such as in attics and crawlspaces, can result in energy savings of 10% or more for the average American home.
- Many sustainable building projects take advantage of orienting the building to use passive solar energy as heating and breezeways as cooling. Orienting the building properly can also pave the way for the efficient use of renewable energy such as solar panels.
Once the energy needs of the home have been reduced as much as possible, the next step is to find ways to generate the energy that the home does need. The most common way to do this is through solar panels, which can be installed on the roof or ground-mounted. Solar panels convert sunlight into electricity, which can then be used to power the home. By storing the electricity produced, solar power can continue to power the home at night. Photovoltaic energy is the most popular way to power zero-energy homes, and there’s even a system in place to designate “net-zero ready” homes, where everything is in place but the solar panels.
Geothermal energy is another option for powering net-zero homes. Geothermal energy comes from the heat of the Earth’s core, and it can be used to heat and cool homes as well as generate electricity. While not every property has the same potential to harness geothermal energy, in the places that can take advantage of it, it’s a constant source of power, unlike solar and wind energy. Geothermal heat pumps and solar roof panels have been combined to great effect to power entire net-zero communities.
Wind turbines are a popular source of renewable energy but don’t tend to be as useful in urban residential applications, due to the disruption of wind patterns. In rural areas, however, wind energy has potential. Hydroelectric systems, too, are a situational use when it comes to net-zero homes.
Looking to the Future
As more and more people become interested in sustainable living, it’s likely that net-zero homes will continue to grow in popularity. With advances in technology, it’s becoming easier and more affordable to implement sustainable building practices, making it possible to reduce the impact of residential and commercial buildings on the environment.
Contributing Author: Matthew Bizzarro, BIZZARRO
Matthew Bizzaro is a passionate advocate of his Upper Manhattan community and is the elected chairman of the REBNY Upper Manhattan Residential Brokerage Committee. Matthew founded BIZZARRO in 2013 with the goal of guiding and serving home buyers and sellers through the complicated New York City market.