By Harvey Bowers, ACAT Treasurer
In October the 2013 Solar Decathlon occurred in Irvine, California. Nineteen homes were built by University students for the competition. All the homes easily met or exceeded the Net Zero Energy Standard. Solar Decathlon has become the design proving ground for Net Zero Energy homes. The Decathlon is closely followed by the building industry worldwide.
The U.S. Department of Energy started the Solar Decathlon in 2002. Initially 20 universities would be selected every two years from applications worldwide. Pre-qualified students would design and build a Net Zero Energy (NZE) home for display on the Mall in Washington D.C. for two weeks. During the early years the German students dominated with their energy systems. The homes are judged in architecture, market appeal, engineering, communication, and affordability. The homes are also measured in comfort zones, hot water use, appliances, home entertainment and energy balance.
To date 112 Universities have participated with 16,800 students in the North American competition. Now there are three solar decathlons, one in North America (Irvine, CA 2013), one in Europe and one in Asia (China 2014). Internationally, 149 universities and 39,000 students, mostly architecture and design and engineering and business students have been involved, including some students from Alaska. The students must fundraise, plan and design, analyze and build. Finally they must transport and re-erect their Solar Decathlon home at the competition site. This is no small task, even if you are a home developer. Between the students and sponsors they have begun to address many of the major issues within buildings, not just energy and sustainability. Many of these homes can supply more than enough energy to supply the home and can also charge an electric car for 30,000 miles per year. University of Maryland won in 2011 with their water recycling and growing the occupant’s food via living walls. In 2013, nearly all the student teams added water recycling and living walls with food production to their solar decathlon entries.
As Net Zero Energy has matured with the Solar Decathlon we see the home is becoming much more efficient and affordable. Nearly all the windows and doors seen in these homes have higher insulation values and sealing systems, than almost any seen in Alaska. This means many manufactures are now offering better products to suit our Alaska climate.
Many of the homes displayed in 2013 focused on affordability and design as entry level or retirement homes for people on fixed incomes. A second observation not seen in the past is how students are trying to design homes that can meet the occupant’s needs should the utility grids fail. All the solar Decathlon Homes were grid connected with provisions made in case the grid is no longer online. Recent weather events may be bringing this issue to a national audience. For Alaska this may be good. Our market is too small to drive research and development. Seeing a large audience may spur development.
The 5th generation Solar Decathlon homes are incorporating much simpler mechanical systems. Energy Efficiency is now viewed as top billing so energy and heating systems can be greatly reduced. Energy Efficiency has progressed to the point that solar electric systems have been greatly downsized compared to homes just a few years ago. Most of the homes had around a 7 kW solar Electric (PV) system. Half of this was to power an electric car. Mechanical rooms used to be very complex. Many of these homes did away with mechanical rooms. Heat Recovery Ventilation systems and a Domestic Hot Water tank is part of Solar Heating and storage. Most Heating systems were small mini split heat pumps or electric. The mini split heat pumps are air to air heat pumps. They can now operate down to -17 degrees F.
Adding living walls as part of the design both inside and outside was very well received by people touring the homes. Plants were part of the design, providing food and used as part of air quality and humidity control.
A new development is the vacuum insulation panels (VIP). These can offer up to R60 for 1-inch thickness. The vacuum insulation panel could be the Holy Grail for Alaska, especially for remodeling. This thin insulation could allow us to meet the insulation requirements we need and be competive with hot climates. When I say competitive I refer to the money spent on energy, whether home or business. The vacuum insulation panels were developed for organ transplant shipment. Refrigerator and freezer manufactures began using them and now we are seeing them in home building envelopes. They remind me of a foil pouch with some insulation under a vacuum, much like our fish packing.
For more information there are several web sites that may be of interest. http://www.solardecathlon.gov/
Also if you Google Solar Decathlon you can access all participants’ sites. There is a huge amount of information. Much will not apply to Cold Climates. If you do a bit of searching within these sites you can access the products used to build the homes and things like appliance selection. In items like appliances you can save a lot of research time. Some teams have done a lot of research and go into the details of their appliance selections and why.
Cold climate Homes in the 2013 Solar Decathlon: http://www.solardecathlon.gov/
Norwich University, Vermont
Middlebury College, Vermont
Team Austria, took first place
Team Alberta, Canada
Team Ontario, Canada
Another web site that may be of interest is a home built at the Great Park (site for 2013 Solar Decathlon) in Irvine, CA This Net Zero Energy home is open to the public until next fall. It will then become a habitat for Humanity home.
ABC Green Home NetZero energy home http://www.abcgreenhome.com
The Net Zero Energy Summit was held in conjunction with the 2013 Solar Decathlon. The Summit was in Irvine, CA. Many of the larger cooperate sponsors were Canadian Energy Companies who see energy efficiency as a renewable resource, partly because companies like BC Hydro and Ontario Hydro can sell to US markets at unregulated electric rates.
Maybe the best thing that could happen is to deregulate electric companies and treat them more like cell phone companies.
A number of top scientists spoke telling us that we had only 6 years to start reversing the Earths CO2 rising. This year CO2 levels reached 400 PPM which has not occurred in the last 4 million years. Unless we can reverse this trend quickly, humans and many other species may be is serious trouble. A group called “2030” thought we could stop CO2 rising and climate change by getting new buildings to meet Net Zero Energy standards by 2020 and address all existing buildings by 2030. By adjusting our building goals we could save the planet, spur economic growth and live in greater comfort.
We heard about a University of North Carolina study which looked at 71,000 homes financed between 2002-2012. Energy star homes were 32% less likely to default. Energy efficient homes allow homeowners to put their money into mortgage payments or other investments rather than monthly utilities.
We heard from lots of small home builders and major building contractors that are already building NZE all over North America. CanmetENERGY, Natural Resources Canada does Canadian Research in Building. They presented a great presentation on the studies of about 14,000 energy efficient homes with up to 10-20 years of data. Canmet indicated we have over 200,000 building options available now to meet NZE.
I had the opportunity to meet and talk to builders who have built entire NZE subdivisions. Some of these builders could build all the homes built in Mat-Su in a season or two. I had lunch with builders that had already used vacuum insulation panels (VIP). Their driving incentive in their market is their very high land costs. Getting R-60 in a thin wall had market advantage. We also heard a number of presentations on Building Optimization on large projects. With this approach they were able to meet NZE standard with lower costs than conventional construction. Air to air, mini split heat pumps are becoming plug and play and efficient to -17 degrees. These may play a role in the future of Alaska.
The Net Zero Energy Summit was hosted by Net Zero Energy Home Coalition which has great webinars every few weeks on net Zero Energy Homes www.netzeroenergyhome.ca
Alaska’s current 5 Star Plus buildings would meet moderate climate, lower 48, needs and be energy efficient enough for NZE ready. To meet NZE in many parts of Alaska we will need an R60 shell. In Fairbanks and North we may need R100 shells plus some wood heat in our 3 to 4 months of no solar.
Net Zero Energy Coalition membership, webinar presentations www.netzeroenergyhome.ca