By Holly Haber  

The Net Zero Energy Home of Tomorrow shown at the State Fair of Texas this year was a fully furnished model home.  It has all of the features that you might expect: solar panels, solar hot water system, LED lights, energy efficient appliances, and a smart heating and cooling system. Net Zero means that it produces as much energy as it uses.






I asked the staff: what’s the quickest, most economical way to reduce energy use in a new home. Insulate your roof with airtight spray foam, according to Andrew McDonald, business manager at Scarlett Custom Homes and Remodeling in Frisco, which specializes in green homes.  Made by Bayer of urethane with 2 percent soy, the foam insulates the air in the attic to maintain a temperature of about 85 degrees Fahrenheit in the summer and 55 in winter, according to Herve Brechoteau, a sales rep for Greenland Energy Dynamics in Addison.




Photo Credit Greenland Energy Dynamics

The foam hardens into an unscented, spongy airtight glob that keeps out dust and allergens, he said. It costs $1.70 per square foot of roof, which translates to about $4,080 for a 2,000 square foot home. The price varies depending on the pitch of the roof, which affects the square footage.

It will instantly lower your heating and air conditioning bills by 30 percent, McDonald noted.  There’s a hitch if you have gas heat -- the attic can’t be entirely closed to ventilation unless you have a high-efficiency furnace. It can still be done but without the airtight seal, Brechtoteau said.  Of course, if your furnace needs replacement, that’s the perfect time to invest in a high-efficiency model, which costs about $500 to $700 more than a conventional system.

The Net Zero home also features an 80-gallon Rheemglas solar hot water heater, which will set you back a hefty $8,000 but does earn a 30 percent tax credit.

The sales reps also discussed a  geothermal heating systems, which cut energy use by 70 percent by pumping heat from or into the earth. These systems are ideal for new construction but can also be retrofitted to old homes.  Each ton of heat generation requires drilling a shaft that is 4.5 inches wide and 300-foot deep, and they all must be spaced 20 feet apart, Brechtoeau said, A 2,000 square-foot home would typically require digging four holes that each cost $6,500, meaning the system would cost $26,000 for the system. Like the solar water heater, it also qualifies for a 30 percent tax credit.

One of the interesting comments about the House of Tomorrow is that although it is Net Zero it may still not qualify for LEED certification.

Photo Credit Greenland Energy Dynamics

Your comments on this article are invited.