September 20, 2013 By Wayne Hanson
Garrison Keillor tells a story about a dying man who assembles his family for some final words. He asks if his wife is there, and she is. The man then goes down the list of family members, and yes, everyone is gathered there in the upstairs room. As they lean close for his last words, he asks "Then why are all the lights on downstairs?"
Energy efficency has moved from family anecdote to the scientific mainstream and one year ago, Digital Communities covered the launch of a "Net Zero Energy" house on the grounds of the National Institute of Standards and Technology (NIST) in Gaithersburg, Md. The house -- actually a two-story 2,700-square-foot energy lab -- is airtight, heavily insulated, and features solar and geothermal systems for heating and cooling. Nobody lives there, but NIST simulates the comings and goings of a family of four with normal heating and cooling patterns, running showers, cycling a washer and dryer, opening and closing doors and sometimes leaving the lights on downstairs.
The idea was to produce just as much energy as was consumed -- net zero energy use -- and actual operation would be compared to computer simulation benchmarks to see how close to net zero the house would get. A year later, with preliminary results from this summer, NIST has reason to be happy.
According to A. Hunter Fanney, chief of NIST’s Building Environment Division, the instrumentation, virtual family and necessary software was developed, and energy data collection began July 1. Today, NIST reported that since that date, the house produced 623 kWh more energy than required to meet all the needs of a typical family of four.
"In the near future," Fanney said, "we will be adding monthly results which will break down where the actual energy is being consumed with the house."
It should be very interesting to follow the statistics through the winter months. It is certainly a much more scientific way of saving energy than yelling "Who left that door open? Were you born in a barn?"