House with a robot family achieves net zero energy (With Video)
NIST house, photo by NIST
For the past year an experimental house run by the National Institute of Standards and Technology (NIST) has been using a virtual family to prove the ability to create production built net zero energy homes. Having achieved net zero energy in my own 113-year-old home, the results were not surprising.
Check out the video:
The net zero energy house reached its one year anniversary on July 1 with enough surplus energy to power an electric car for about 1,440 miles. Even more impressive, the home accomplished this despite five brutal months of record breaking cold temperatures and snowfall. The typical family in Maryland (where the home is located) has an average annual electricity bill of $4,400.
Yet this all-electric house produced more energy than it used and exported the excess energy back to the utility company. For the net zero home's occupants, a computer-simulated family of two working parents and two children, ages 8 and 14, the total annual energy cost would equal $0.
The exciting news is that many states are taking steps toward requiring or encouraging homes to be able to be net energy producers. California will require new homes to be net zero energy by 2020.
This test house is impressive because it proves my point that net zero energy is not a challenge, but a choice. Even though the solar panels were covered in snow for 38 days, they still produced more energy than was needed for insane levels of comfort. The house is 2,700 square feet. That's twice the size of the average American home in 1970 and much bigger than most houses in the rest of the world. With the trend toward smaller, better-built homes and away from McMansions, net zero energy is fast becoming an easy target for the average homeowner.
According to NIST, "In terms of energy consumed per unit of living space -- a measure of energy-use intensity -- the NIST test house is calculated to be almost 70 percent more efficient than the average house in Washington, D.C., and nearby states."
"The most important difference between this home and a Maryland code-compliant home is the improvement in the thermal envelope -- the insulation and air barrier," says NIST mechanical engineer Mark Davis. By nearly eliminating the unintended air infiltration and doubling the insulation level in the walls and roof, the heating and cooling load was decreased dramatically.