I bought the house — the first completed at
Green Acres ( greenacresnewpaltz.com) — in
March 2009. For a full year, I and my two young
sons, Evan and Camden, lived in it, using energy
the way most American families do — drying our
clothes in the machine, running the dishwasher
regularly and so on. On March 26, we completed
a year in which our 10-kilowatt (k W) photovoltaic (PV) system generated more energy than
we used. Additionally, an electric ground-source
heat pump provided all cooling and heating
needs of the home very efficiently, enabling us
to achieve our net-zero-energy goal. The second
of five occupied homes in this 25-home community is well on its way to achieving net-zero
energy, too, having shown similar consumption
and solar generation patterns.
Although a number of developments planned
or under construction have NZE houses as their
goal, Green Acres appears to be the first NZE
single-family development in the United States
in addition to a photovoltaic system (upper right), geothermal heating and cooling, high-efficiency windows and insulated concrete form construction, Shepler’s house features an open, modern design with
a floating staircase on the main floor (above, left) and a daylit basement (bottom right). To record the
performance of the home for a full year without complication, the woodstove was left unused.
to have a home that has achieved this goal. As
the first resident of Green Acres, I’m proud to
tout the accomplishments of the builder, Anthony Aebi of Greenhill Contracting (greenhill
contracting.com). His bold commitment to produce nothing but zero-energy or near-zero-ener-gy homes of superior materials and durability is
to be celebrated and emulated. If he can achieve
net-zero-energy in New york, where solar and
wind resources rank far behind those in other
regions, then it can be achieved virtually anywhere in the continental United States.
Getting to a Better Way of Building
Aebi began his career building traditional
“stick-built” homes. That changed after 10 years
in the business, when he was inspired by what
he observed during a family visit in Switzerland.
Aebi came to believe the “throw-away” construction practices in the United States were unconscionable, trading cheap upfront costs for long-term structural problems. looking for a better
way, he discovered the insulating concrete form
(ICF), which promised centuries (rather than
decades) of durability. Recognizing that the ICF
also offered the potential for an airtight building envelope and decent R-values (up to R- 22),
Aebi began considering other energy-efficiency
features, such as spray-foam insulation in the
rafters, on-site PV and geothermal heating and
cooling. As he began to see that available commercial technologies could actually achieve net-
David Shepler works for IBM Research at the T. J. Watson Research Center in Yorktown Heights, N. Y. He is the program manager for IBM’s Jeopardy! Challenge, an effort
to demonstrate advanced computer question-answering technology by competing against human players in the game of Jeopardy! Shepler has also contributed to
IBM Research efforts to partner with federal and state government to develop alternative energy and energy-efficiency technologies. Shepler spends much of his free
time advocating for energy-efficient living and building practices, including spreading the word on the efforts of his builder, Anthony Aebi of Greenhill Contracting.
Shepler lives with his sons, Evan and Camden, in New Paltz, N. Y. He can be reached at firstname.lastname@example.org.