Thursday, February 18, 2010

Zero Energy Homes for the Rest of Us

While visiting St George Utah recently, we found that we were in
town during the parade of homes, so we looked at a few of them.  One of the
display homes was a very efficient home built by Sun-Savvy Inc.  I was very
impressed by this home and the other homes they offer.

SunSavvy1.JPG


Their design combines a very good and very tight thermal envelope, heat
recovery ventilation, passive solar, solar thermal and PV arrays, and efficient
mini-split heat pumps to make a home that should be able to achieve net zero
energy use in the southern Utah climate.  The display home has a LEED
Platinum rating. 


Even more impressive to me is that these are very nice and very "normal"
looking homes.  These homes appear to be very easy for the homeowner to live with. 
While the energy efficiency does add some cost, the homes appear to be cost
competitive with ordinary construction homes.  In other words, these are
net zero or near net zero energy homes which should have a very wide appeal to
ordinary home buyers -- you don't have to be an eco-freak (like me) to like
these homes. 

We took the full tour, got a lot of pictures -- all the details here...

Much more on solar homes here...

Clerstory.JPG
Clerestory windows -- great daylighting.  These open automatically when a set temperature is exceeded.

Ventilator.JPG
The energy recovery ventilation unit -- an earthtube is used to precondition the intake air to the ventilator.

It seems like a lot of the "net zero" energy homes you see are a long ways
out of the mainstream -- they tend to be architecturally unique (some would say
strange) and come with an acre of PV panels that would add $100K+ to the cost of
the house were it not for some very very generous (and perhaps questionable)
rebate programs.  I don't see this type of near zero energy home ever
catching on and becoming widespread.  On the other hand, a design like the
Sun-Savvy homes seems like it could have very wide appeal.  I hope it turns into a trend.


Gary