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Seeing Growth in Green: the 2009 Solar Decathlon

The U.S. government, through the Department of Energy (DOE), hosted the biannual Solar Decathlon in October 2009. 20 teams competed in 10 contests to determine which team designed, constructed, and operated the most attractive, energy-efficient solar-powered house.

By Kimberly Del Bright

President Obama's American Recovery and Reinvestment Act, signed into law on February 17, 2009, proposed to spend $787 billion to create and save jobs, particularly by investing in domestic renewable energy. According to Laurence Shatkin, an occupational expert, many new jobs for engineers are in the green technology sector. In his book, 200 Best Jobs for Renewing America, Shatkin forecasts 20% job growth with average annual earnings slightly above $70,000 for environmental and industrial engineers as businesses look for ways to reduce energy and operational costs, particularly in construction industries.

To support this initiative, the U.S. government, through the Department of Energy (DOE), hosted the biannual Solar Decathlon. In October 2009, 20 teams competed in 10 contests to determine which team designed, constructed, and operated the most attractive, energy-efficient solar-powered house. Undergraduates from the United States, Spain, Germany, and Canada brought their homes to the National Mall in Washington, D.C., to create a solar village. At the opening of the competition, Energy Secretary Steven Chu announced $87 million will be made available to speed adoption of solar energy nationwide and increase the probability of new scientific breakthroughs. "The projects will help accelerate the use of solar energy by residents, businesses, and communities and promote the long-term viability of solar energy by investing in the technologies of the future," said Secretary Chu.

One of the teams in this year's event is from The Pennsylvania State University in University Park, Pennsylvania. Over 92 students from 13 disciplines (e.g., architectural engineering, environmental engineering, materials, mass communications, supply chain) participated in bringing the team's entry, Natural Fusion, to reality. The 796-sq. ft. exterior, one-bedroom, one-bathroom home has 5.6 kW solar power capacity; 5.2kW—27 thin-film, cylinder-shaped photovoltaics individually rated at 191 W; and a 450 W tracking solar awning. The cost of the home, including all systems, equipment, and transportation is approximately $283,000. The team's faculty director is Dr. Jeffrey R. S. Brownson, researcher and professor of energy and mineral engineering, and the team's media liaison is Thomas Rauch, an undergraduate in Energy, Business and Finance. They shared their perspectives on green technologies, solar power, and the competition.

Why did you join the Solar Decathlon Team?

Brownson:We all sense the great capacity of the sun from its warmth and light, the foods that we grow, and the wind that shapes the weather. My passion is developing solar energy in society as a major supplier of global heat and power. When the initial students approached me to support their effort, I saw a mirror of that passion and also our future.

Rauch: I came into Penn State with the intention of getting involved immediately. I heard about the Natural Fusion team and within only a few weeks, I started doing little things for the team. Once I had proved myself they let me take on more responsibilities. By the end of that semester, I had a calendar full of to-do lists. The reason I was able to throw myself so fully into the project was that I wanted to dedicate myself to the ideals of the team. I have conviction about our message.

Natural Fusion Solar House

Natural Fusion's Solar House

Why are you personally interested in "green"?

Brownson:"Green" encompasses the ethical conduct of right speech, right action, and right livelihood, which extends "the good life" to the global community in a sustainable manner.

Rauch: Mostly, it's the principle of the matter. There is a basic logic about sustainability that is fundamental to the survival of our people on this planet. We must come up with new ways to support the demands of our advancing and expanding population. "Green" is that movement. "Green" is a major frontier for innovation and creativity.

The house the team built was called Natural Fusion—can you describe the integrative design?

Brownson:Each design element was formed to be both functional and aesthetically pleasing. Natural Fusion is all about blending the design with the environment. For example, the windows and opening glass walls (tri-fold doors) along the southern façade are transparent to "fuse" the interior and exterior landscape, creating the appearance of a larger space within the home. Six gardens (sense, bio-intensive, living wall, wildlife attractant, xeric limestone meadow, and green roof) add greenery and help the home form a bond with the outside.

Rauch:The home has public and private areas separated by the Nexus, or heart of the home. The Nexus is where all the mechanical, electrical, and plumbing reside. The public area is a "great room" combining the living/dining rooms and the kitchen. The island in the kitchen conveniently expands into a table for more seating and to provide a dining room. The private area includes the bedroom and bath. The tranquility of the home is enhanced by making all the parts connected to a green space. For example, the bedroom opens to the sense garden. In every way, the house was designed to blend naturally into the environment.

There are some state-of-the-art technologies for the electrical aspects of the house. What were these?

Brownson:The main source of the solar electric power is from the Green Roof Integrated Photovoltaics, otherwise known as GRIPVs (pronounced "grip-vees"). Natural Fusion is the first residential project to use Solyndra cylindrical panels. Once we found out about them, we knew we wanted to use them. The cylindrical design of the PVs enables the panels to capture more sunlight throughout the entire course of the day—360° of direct and indirect sunlight. Underneath the panels is a white roof that reflects the light passing through the panels to the underside of the collectors, which increases the efficiency of the system.

Rauch:The home faces south for maximum passive solar gain too. A solar awning is mounted above the southern doors, and this helps with shading from the summer sun. On the awning, three silicon cells cover each of the tracking louvers maximizing power production by following the sun. Inverters are used to convert each string of "solar fins" directly to air conditioning before entering the house. Plus, the solar hot water system is pump-less! It requires no mechanical controls or pumps and consumes no energy. We also installed a highly, efficient Energy Dashboard to help the homeowner monitor his/her energy use. We used the Energy Recovery Ventilator (ERV) to provide fresh air to the house without sacrificing the energy contained in the exhaust air stream.

Would you share any observations you made about the future of green technologies, and in particular solar photovoltaic ones, based on your experience at the Solar Decathlon?

Brownson: There is enormous momentum building in the field. Sustainable Energy technologies are on the rise in a manner similar to the growth of the microelectronics industry, including both energy supply, storage, and demand side management of energy use. The interesting note to this development is the global nature of the boom. Early decisions, some as early as 30 years ago, put the United States currently behind the curve in this boom, as opposed to leading the charge. That is not to say that we will stay there! The signs from our young minds—initiative, creativity, passion for a sustainability ethic, civic-minded responsibility, skill in communication—suggest that American efforts will propel the field forward with the newest generation of graduates.

Rauch: The future is now. To borrow from President Obama, "We are the ones we've been waiting for." The technology is available and relatively simple to install and in many cases is a good investment for the home. I think that many of the students who are studying these fields are headed into a vortex of innovation that is going to spin out major changes in the way that we operate our infrastructure. Be excited, passionate, and dedicated. Look forward to the hard work ahead as a great opportunity.

What sources of information—books, web, journals, etc.—are on your "short list" for newly graduated engineers if they want to learn more about developments in solar-powered construction?

Brownson: Here's my short list.

I. Solar Photovoltaics:

PVCDROM: http://pvcdrom.pveducation.org/
Build It Solar references: http://www.builditsolar.com/References/collectoranalysisrs.htm
Solar Buzz: http://www.solarbuzz.com/
American Solar Energy Society: http://www.ases.org/
Florida Solar Energy Center: http://www.fsec.ucf.edu/en/

II. Energy Simulation, Design Tools, Costing Tools for Sustainable Technologies:

Solar Engineering of Thermal Processes: text by Duffie and Beckman. An old standard for core knowledge on the solar resource and technologies. http://www.amazon.com/Solar-Engineering-Thermal-Processes-Duffie/dp/0471698679
UW Solar Energy Laboratory: http://sel.me.wisc.edu/
TRNSYS software: http://www.trnsys.com/
Energy Design Tools: http://www.energy-design-tools.aud.ucla.edu/
RETScreen software: http://www.retscreen.net/ang/t_software.php
Passive Solar Design: http://passivesolar.sustainablesources.com/
SMARTS software: http://www.nrel.gov/rredc/smarts/
Google SketchUp and the SunTools plugin: http://tx.technion.ac.il/~arrguedi/SunTools/dwnld_after_reg/STdwnld.htm

Rauch: A ton of information is available about these topics. Probably the best bet to keep up with the industry is to get in on one of the solar industry journals. Check out Solar Energy Industries Association (SEIA). Personally, I read Scientific American every month, which is a great resource on all scientific advancement. You never know what will bring about your next great idea. Finally, look for podcasts, which are the easiest way to keep on top of news and information as far as I'm concerned.

The final judging evaluated the home's architecture, marketability, comfort, home entertainment, lighting design, and the incorporation of solar energy features. This year a new net metering contest was used to measure how much net energy was obtained. Despite the Natural Fusion team's best efforts, it did not win the competition this year. Germany did—just like 2007. (For more information on the final scores, go to www.solardecathlon.org.) One thing is for certain: job growth is likely for engineers in the United States and globally in green technologies, particularly in renewable energy innovation.

Kimberly Del Bright is a writer and educator at the Pennsylvania State University in the College of Earth and Mineral Sciences. Her work has appeared in journals, newspapers, and magazines.

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