On June 7th, the DOE, Builders Challenge program issued its formal certification of the HERS (Home Energy Rating System) rating for The S.E.E.D. Home; it received an astounding rating of HERS 20!  Very close to the holy grail of ’0′.  As it turns out, the only reason it did NOT receive a HERS ’0′ is because the final rating category has to do with only the end user and how much electricity they might use for TVs, computers, game boys, hair dryers, etc., etc.

However, it is my belief that anyone interested in an efficient home is going to be mindful of their energy use habits. That being said, I have no doubt that The S.E.E.D. Home performance in terms of electrical energy usage will in fact be a true net zero home.

One of the most outstanding aspects is the RADIANT FLOOR COOLING performance. The reverse cycle chiller 2 ton heat pump operates ONLY between the hours of midnight and 7 am! That’s it. The floor is cooled to a comfortable 72 degrees with the corresponding air temp being 75 degrees. This reading is taken at 7am. By the end of the day the temperature rise is only 3 degrees, a corresponding 75 degree floor with a 78 degree air temperature! It is like being in a cave wherein the ENTIRE air space is a consistent and near constant temperature throughout every square foot of the home. There are NO hot or cold spots created by forced air movement from an air handler – just cool consistent temperatures throughout the day and night. Then at midnight, the compressor kicks in recooling the exposed aggregate concrete floor to 72 degrees and the cycle replays.

This is turning into a cutting edge breakthrough with regard  to cost effective high performance energy efficiency because the compressor ONLY operates in the early morning hours when the outside temps are coolest and therefore the heat pump can operate at its optimum efficiency. Additionally, there is NO cycling of the unit because it is preset to operate for these 7 hours ONLY; the system coasts the remainder of the day and night. The home is so well insulated and sealed that in Tucson’s  current summer temperatures of 110 degrees there is ONLY a 3 degree rise for the entire day. And,remember, the temperature is constant and consistent (within the 3 degree spread) WITHOUT the intermittent cold air blasts from a forced air unit trying to mix with the existing warmed air (thus, no hot and cold areas).

In the meantime The Arizona Daily Star did a feature article (2 page spread) in their At Home section this past Sunday, which included a picture and a blurb on the front page of the section.  You can read the article on their website.

Jeff Beamish of KVOA, channel 4 came out to the house and did an interview that aired on the evening news last week.  You can see the video here.  Unfortunately it can’t be embedded as WordPress doesn’t support flash.

Linda Garret of KGUN 9 news also came out to the house and did an interview which you can see on their site or watch it below.

If  you click the image of the front page and you can see an enlarged view of the header (will open in new window or tab), containing a picture of the rendering of the home, directing you to the article entitled Take a walk through a thermal envelope.  It’s in PDF format and you will have to scroll down to page 15.

The open house had a great turn out.   Below are  several video clips of some of the discussions and questions and answers.  Our visitors were intelligent, well informed, asked great thought provoking, questions and sparked some very interesting discussions.  All in all I would have to say it was a success. We are extremely happy about the excitement this project is generating in the community.

click the pics for larger view