Grantee Research Project Results
Final Report: S.T.E.P. (Solar Thermal/Electric Panel):Full-Scale Performance Data and Energy Testing
EPA Grant Number: SU832487Title: S.T.E.P. (Solar Thermal/Electric Panel):Full-Scale Performance Data and Energy Testing
Investigators: Baur, Stuart W. , Krueger, Chris , Lamson, Joel
Institution: University of Missouri - Rolla
EPA Project Officer: Page, Angela
Phase: I
Project Period: October 1, 2005 through May 30, 2006
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2005) RFA Text | Recipients Lists
Research Category: P3 Challenge Area - Air Quality , Pollution Prevention/Sustainable Development , P3 Awards , Sustainable and Healthy Communities
Objective:
The use of solar energy acquiring devices have been slow to gain acceptance due to their lack of visual appeal to the average homeowner as well as their extra expense. 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, although not usually encased in glass like the system to be tested, but there are no data to quantify the overall efficiency per unit area of the independent systems to the hybrid system. The basis for hybridizing the two systems is simple; because solar panels are only 10% efficient, on the average, the other 90% 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 because the solar panel is behind glass and the thermal system will only be starting out with the 90% waste heat. The system needs to be in a glass enclosure to amplify the trapped heat from the sun’s radiation to reach desired domestic hot water temperatures that exceed 110º F. 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 initial experiment was on a scale of three panels covering 25 square feet. The three panels were the hybrid panel, the stand-alone photovoltaic panel and the stand-alone thermal (hot water) panel. This proposed experiment will encompass 160 square feet of just the hybrid S.T.E.P. (Solar Thermal/Electric Panel) system and acquire performance data for input to computer simulation software and to optimize the system for application to the UMR-RTI solar house that is entered into the 2005 DoE’s Solar Decathlon. The obvious benefit to the planet of implementing a S.T.E.P. type system would be the reduction in energy consumption and the impact on the environment resulting in the improvement in human living conditions.
Summary/Accomplishments (Outputs/Outcomes):
Not only is the S.T.E.P. hybrid system effective in its aesthetics but it also is more efficient than its two stand-alone counterparts. The estimated overall efficiency of the S.T.E.P. system is estimated to be 50%, while the efficiency of a separate thermal and separate electric system is estimated to be 26% for the same roof area. 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 2400 square feet, the roof area of an average sloped house would facilitate the placement of 12 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 10 cents a kWh. This would essentially save the owner $1070 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 and the rated life of the solar panels is 26 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 conducted during the spring semester of 2006 at the University of Missouri–Rolla demonstrated that a hybrid roof system showed a 50% overall efficiency, while a separate thermal and separate electric system is estimated to have 26% efficiency for the same roof area.
Journal Articles:
No journal articles submitted with this report: View all 1 publications for this projectSupplemental Keywords:
innovative technology, renewable energy, engineering, modeling, monitoring, Midwest, building systems, building industry, sustainability, solar energy, solar panels, RFA, Scientific Discipline, INTERNATIONAL COOPERATION, Sustainable Industry/Business, POLLUTION PREVENTION, cleaner production/pollution prevention, Sustainable Environment, Energy, Technology for Sustainable Environment, Environmental Engineering, Engineering, environmentally preferable products, energy conservation, cleaner production, green design, sustainable development, solar thermal electric panel, clean technology, green building design, alternative materials, green home building, pollution prevention design, energy technology, solar energy, construction material, architecture, alternative energy source, outreach and education, photovoltaics, clean manufacturing designsThe 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.