Grantee Research Project Results
Final Report: UMR’s Design for an Environmental STEP Ahead: Solar Thermal Electric Panels
EPA Grant Number: SU833929Title: UMR’s Design for an Environmental STEP Ahead: Solar Thermal Electric Panels
Investigators: Baur, Stuart W. , Lough, Katie Grantham , Stone, Robert
Institution: Missouri University of Science and Technology
EPA Project Officer: Page, Angela
Phase: I
Project Period: August 31, 2008 through July 31, 2009
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2008) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Sustainable and Healthy Communities , P3 Awards , Sustainable and Healthy Communities
Objective:
Natural disasters such as the wildfires in southern California, tornados throughout the Midwest and Hurricane Katrina have left many families without homes – a large number who are challenged to rebuild their lives with minimal resources. Compounding the situation, the rising cost of current energy resources and a deregulated electrical grid where prices have trended up rather than down, make it harder for those families to maintain a reasonably comfortable home environment once they rebuild. These disasters and their associated new construction efforts pose both a challenge to sustainability as well as an opportunity to improve it. The Missouri University of Science and Technology or S&T (formerly University of Missouri-Rolla) has been developing solutions to this humanitarian crisis and sustainability challenge. The objective of this design project is to leverage state-of-the-art research at S&T and design thermal and electric energy hybrid roof panels in a modular form so that alternative energy sources are available and affordable for typical homes. The expected output of the project will be a modular solar thermal electric panel (STEP) prototype.
S&T has three solar houses currently operating as student residences. These homes are currently sitting atop basement foundations that are equipped with a variety of energy measuring equipment to allow for STEP prototype testing in realistic environments. The expected outcomes of the project will be an experimentally determined cost and energy analysis of the STEP system to evaluate the return on investment for its end users. While the initial end users will be the next Solar House currently under construction at S&T in anticipation of the 2009 Solar Decathlon, the next set of end users are anticipated to be residents of Caruthersville, MO. The students on the design team will visit with Caruthersville, MO, tornado survivors and chronicle their rebuilding to identify their specific building material needs and energy concerns as part of the IDE/Arch E 301 Renewable Energy Systems Modeling course.
The goal of this project is to construct a model of a visually appealing hybridized solar/thermal panel integrated roofing system and test the model under differing conditions. In developing this model, we will show that the hybrid panel will convert more of the sun’s energy per unit area than its stand-alone counterparts. This research applies principles of thermal and electric active solar systems and will demonstrate that the hybrid panel system can make an alternative energy home more desirable than traditional housing without having the panels make the roof unattractive. Combining photovoltaic and thermal hydronic systems has been done before. The basis for hybridizing the two systems is simple; since solar panels are only 10 percent efficient, on the average, the other 90 percent of the available solar energy is given off as waste heat. Why not use that waste heat to condition water. Neither the solar panel nor the thermal system will be as effective as their stand-alone counterparts since the solar panel is behind glass and the thermal system will only be starting out with the 90 percent waste heat. Initial research was investigated during the fall semester of 2004. The initial research results showed that the hybrid panel was one and a half times more effective at converting the sun’s energy than its stand-alone counterparts for the same unit area. The experiment was on a scale of three panels covering 25 square feet. The three panels were the hybrid panel, the standalone photovoltaic panel and the stand-alone thermal (hot water) panel. In the spring of 2005 a larger scale hybrid roof experiment that encompassed a 160 square feet of just the Solar Thermal/Electric Panel (STEP) system was developed and implemented as part of the UMR-RTI solar house and entered in the 2005 Solar Decathlon.
The obvious benefit of implementing a S.T.E.P. type system to the planet would be the reduction in energy consumption and reducing the impact on the environment resulting with the improvement in human living conditions.
Proposed Phase II Objectives and Strategies:
The Phase II objectives and strategies include the further analysis and implementation of the data gathered in the first phase of this report by testing a larger scale model. The underlying drive for this research project is to increase the number of passive energy homes built in the United States and abroad. In so doing, an innovative building systems to increasing overall energy generation is being proposed. Specifically, the scope of this project focuses on increasing the overall energy generation by using a hybridized solar electric and thermal energy panel. The further development of this system would directly improve the building system efficiency and reduce the overall cost of living in a zero energy home.
It is the issue of affordability and convenience that directly impacts the “People” in the P3 grant. This problem definition is focused on the developed world, which has been remarkably slow to embrace sustainable building practices. The people need to see that a zero energy home can be more affordable than a traditional home and at the same time offer similar conveniences. In general, people purchase homes because of location and cost. It is this cost element that is being addressed in this proposal by developing a large-scale model of a combined photovoltaic and thermal hydronic energy system.Summary/Accomplishments (Outputs/Outcomes):
Not only is the STEP hybrid system effective in its aesthetics but also it is more efficient than its two stand-alone counterparts. The estimated overall efficiency of the STEP system is estimated to be 15-45 percent as compared to a separate thermal and separate electric system. An assumption for the thermal systems is that they are of similar makeup and their efficiency is based on an ambient input temperature. If this setup was placed on an average home, of 2,400 square feet, the roof area of an average sloped house would facilitate the placement of twelve times the surface area tested. If the data were extrapolated from the 4-hour test period to an average whole day production the following results would apply. For an average yearly household consumption of 10.7 MWh a year, four times the collector area tested would be needed. Note that the hot water would be used for space heating as well as for domestic use. This does not mean that all of the hot water and energy needs would be met for a particular season because this is based on average numbers. The average cost of electricity is about $0.10 cents a kWh. This would essentially save the owner $1,070 a year in energy costs. The proposed system would cost about $28,000 as specified in this report; this system does not include inverters or batteries, which would add another $8,000 to the system cost, for a fully sustainable system. The payback would be 26 years where the rated life of the solar panels is 25 years. This also is assuming that the price of electricity is stable. The cost of energy is always increasing and the payback would be shorter as prices soar.Conclusions:
Phase I research results, which were investigated during the Spring Semester of 2006 at the University of Missouri – Rolla, demonstrated a hybrid roof system showed a 50 percent overall efficiency while a separate thermal and separate electric system is estimated to be 26 percent efficient for the same roof area.Journal Articles:
No journal articles submitted with this report: View all 3 publications for this projectSupplemental Keywords:
Innovative technology, renewable, engineering, modeling, monitoring, Midwest, building systems, building industry,Relevant Websites:
http://web.mst.edu/~baur/
http://solarhouse.mst.edu/
http://solarhouse.mst.edu/village.html
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.