Saturday, February 26, 2005
Low Cost, High Efficiency Homes Roundup
Near Zero Energy ApartmentsPALO ALTO, Calif.--(BUSINESS WIRE)--Feb. 25, 2005--Clarum Homes has just completed the construction of the Vista Montana apartment community in Watsonville, California which houses the nation's largest building integrated solar electric system ever installed in an apartment community. GE Energy supplied the 60-kilowatt system for the complex, making it possible for this community to produce over 90 megawatt hours of electricity annually. ...
Along with the building integrated photovoltaics, the near zero energy apartment complex includes tightly sealed duct work, a high-efficiency heating and ventilation system, and low-e windows. This complex was designed for larger families with income ranges at 50%-60% of Santa Cruz County area median income levels. It also has a community center with after-school programs for kids.
"With skyrocketing energy costs and continued concerns over energy shortages, Clarum's entire company focus is to combine renewable building practices and alternative energy solutions with affordable and entry-level housing," said John Suppes, Vice President of Clarum Homes. "Not only do renewable building practices and energy efficient systems make sense for the environment, but they also provide a more comfortable and healthier environment to live in."
Ultra-Low Energy Residences
In the January 2005 edition of ASHRAE Journal, there is an article about a study done by the DOE's Building Technologies Program. For this study, four homes were built and their energy usages were compared after a year to those of traditionally-built homes of the same sizes. The control homes were built specifically for this purpose and all by the same contractor. All homes were located in east Tennesseeby the Habitat for Humanity Loudon County Affiliate. The near zero energy homes were built using structural insulated panels (SIP's), and included high-efficiency heat pumps and water heaters, controlled ventilation, compact fluorescent lights, Energy Star applicances, heat recovery showers, insulated water pipes and large roof overhangs, and 2 kW photovolatic systems.
The ZE homes performed better in many areas. The base homes were between 6 to 14% more leaky than the ZE homes. The ZE homes used less energy for domestic water heating and for heating and air conditioning. The occupants of the ZE homes reported no thermal comfort complaints. The ZE homes used about 40% less total energy than the traditional houses. Overall, the cost to the homeowner over the year was $343, or $0.94 per day.
The first cost of these homes, although similar in size (around 1000sf), was higher than that of the traditional homes. The traditional ones cost $73,000 and the ZE homes cost around $116,000. The authors anticipate that the costs of these homes will be lower with greater familiarity with the structural and HVAC technologies, and with rebates for PV and geothermal systems. Additional research is leading to cost reductions in the envelope, domestic hot water heat pump, and geothermal heat pump.
Modular Efficient Homes
Treehugger has quite a list of modular, inexpensive, and efficient homes.