Efficiency Curves of Types of Solar Collectors InspectAPedia® -
Solar Collector Efficiency Curves
Comparing efficiency of different types of solar collectors
Unglazed flat plate solar collectors, single glazed flat plate solar collectors, double glazed flat plate solar collectors, conventional stationary solar collector, evacuated flat plate solar collector, advanced stationary solar collector, tracking parabolic trough solar collector efficiency comparisons
Historical data on solar collector efficiency
Solar Age Magazine Articles on Renewable Energy, Energy Savings, Construction Practices
Questions & answers about solar collector design, types, & solar collector efficiency
This article discusses the relative efficiency of different types of solar collectors, including a comparison of the effectiveness of Unglazed flat plate solar collectors, single glazed flat plate solar collectors, double glazed flat plate solar collectors, conventional stationary solar collector, evacuated flat plate solar collector, advanced stationary solar collector, tracking parabolic trough solar collectors.
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Graph of solar collector type efficiency curves (solar collector efficiency is on the vertical axis) at page top and accompanying text are reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss.
Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
The question-and-answer article below paraphrases, quotes-from, updates, and comments an original article, (see links just above) from Solar Age Magazine and written by Steven Bliss.
Comparing the Efficiency of Tracking, non-Tracking Solar Collectors & Flat-Plate vs Evacuated-Tube Solar Collectors
Question:
What is the percent difference in solar energy collecting efficiency between tracking and non-tracking solar collectors?
What is the percent difference in solar energy collection efficiency between flat-plate and evacuated-tube solar collector arrays?
-- Michael Jackson, Alliance OH
Answer:
The accompanying graph, from a publication of Canada's National Research Council, shows solar collector efficiency curves for three kinds of flat plate solar collector, two types of stationary concentrating solar collector, and a tracking parabolic-trough concentrating solar collector.
Solar collector efficiency is shown on the left vertical axis in the graph.
As you can see, differences in solar collector efficiency depend on the temperature range in which the solar collectors will be operating.
Unless you plan to use the solar collectors for high-temperature applications and are willing to pay for more complex solar equipment that will produce higher efficiencies, you may be better off with less expensive stationary flat-plate collectors.
(See "Rising Hopes for Vacuum Tube Solar Collectors", Solar Age 6/82.)
The question-and-answer article about efficiency differences among different types of solar collectors provides historical solar collector efficiency data from the 1980's and, quotes-from, updates, and comments an original article, (see links just above) from Solar Age Magazine and written by Steven Bliss.
The link to the original Q&A article in PDF form immediately below is provided by the above expanded/updated online version of this article.
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Solar Age Magazine was the official publication of the American Solar Energy Society. The contemporary solar energy magazine associated with the Society is Solar Today. "Established in 1954, the nonprofit American Solar Energy Society (ASES) is the nation's leading association of solar professionals & advocates. Our mission is to inspire an era of energy innovation and speed the transition to a sustainable energy economy. We advance education, research and policy. Leading for more than 50 years.
ASES leads national efforts to increase the use of solar energy, energy efficiency and other sustainable technologies in the U.S. We publish the award-winning SOLAR TODAY magazine, organize and present the ASES National Solar Conference and lead the ASES National Solar Tour – the largest grassroots solar event in the world."
Steven Bliss served as editorial director and co-publisher of The Journal of Light Construction for 16 years and previously as building technology editor for Progressive Builder and Solar Age magazines. He worked in the building trades as a carpenter and design/build contractor for more than ten years and holds a masters degree from the Harvard Graduate School of Education.
Excerpts from his recent book, Best Practices Guide to Residential Construction, Wiley (November 18, 2005) ISBN-10: 0471648361, ISBN-13: 978-0471648369, appear throughout this website, with permission and courtesy of Wiley & Sons. Best Practices Guide is available from the publisher, J. Wiley & Sons, and also at Amazon.com.
Excerpts with updates and annotations expanding the original Best Practices Guide text can be found in the online review and book summary at BEST CONSTRUCTION PRACTICES GUIDE and also at DECK & PORCH CONSTRUCTION, at INDOOR AIR QUALITY IMPROVEMENT GUIDE, and in other articles found at InspectAPedia.com such as HOUSEWRAP AIR & VAPOR BARRIERS, SOUND CONTROL in buildings, and other topics.
Passive Solar Design Handbook Volume I, the Passive Solar Handbook Introduction to Passive Solar Concepts, in a version used by the U.S. Air Force - online version available at this link and from the USAF also at wbdg.org/ccb/AF/AFH/pshbk_v1.pdf
Passive Solar Design Handbook Volume II, the Passive Solar Handbook Comprehensive Planning Guide, in a version used by the U.S. Air Force - online version available at this link and from the USAF also at wbdg.org/ccb/AF/AFH/pshbk_v2.pdf [This is a large PDF file that can take a while to load]
Passive Solar Handbook Volume III, the Passive Solar Handbook Programming Guide, in a version used by the U.S. Air Force - online version available at this link and from the USAF also at wbdg.org/ccb/AF/AFH/pshbk_v3.pdf
"Passive Solar Home Design", U.S. Department of Energy, describes using a home's windows, walls, and floors to collect and store solar energy for winter heating and also rejecting solar heat in warm weather.
Solar Collector Efficiency Study: "A COMPARATIVE SIMULATION STUDY OF SOLAR FLAT-PLATE
COLLECTORS DIRECTLY AND INDIRECTLY INTEGRATED INTO THE
BUILDING ENVELOPE",
J. Metzger1, T. Matuska1, and H. Schranzhofer2
1Czech Technical University, Faculty of Mechanical Engineering, Department of
Environmental Engineering, Technicka 4, 166 07 Prague 6, Czech Republic
2Graz University of Technology, Institute of Thermal Engineering,
Inffeldgasse 25/B, 8010 Graz, Austria
Building Simulation 2009, Eleventh International IBPSA Conference,
Glasgow, Scotland,
July 27-30, 2009
Document: http://www.ibpsa.org/proceedings/BS2009/BS09_0805_810.pdf
Abstract: Simulation analyses for solar combisystems
(domestic hot water productionand space heating)
with different levels of collector quality (atmospheric
and evacuated flat-plate collectors) and different
types of façade integration (direct, indirect) have been performed. For the direct integration of solar
collectors into the building facade, a simple collector-facade model has been used (TRNSYS)
while indirect integration with a naturally ventilated
air gap between collector and facade has been
investigated with a newly developed collector-facade
model representing the air flow in the gap induced by
wind or buoyancy (TRNFLOW). The highest performance has been achieved by direct integration
of high efficient evacuated flat-plate collectors
directly integrated into the façade.
Solar Collector Efficiency Study: "Comparative study of air heating solar collectors",
J. Naga Raju,
Instrumentation and Services Unit, Indian Institute of Science, Bangalore 560012, India, International Journal of Energy Research,
Volume 15 Issue 6, Pages 469 - 471, 14 Mar 2007:
Abstract Three types of conventional solar air heater are designed such that their heat absorbing areas and the pressure drops across them are equal for equal air mass flow rates per unit collector area. The results of thermal performance tests conducted simultaneously on these collectors, under the same environmental conditions, are presented.
"Solar Collector and Storage Kit Made with Tire Inner Tubes", Investigators: Moaveni, Saeed , Tebbe, Patrick
Institution: Minnesota State University - Mankato, August 15, 2008 through August 14, 2009, National Center for Environmental Research, US EPA,
Quoting from the proposed study: Approach: A number of collector designs will be considered. Each design will be analyzed and tested for thermal performance, and ease of assembly. Once the most cost effective design with the best thermal performance is identified, an easy-to-assemble solar collector kit will be created. Because the proposed project makes use of solar energy, it reduces the need to burn dry-wood to heat water, and as the result it reduces pollution and the consequent hazards to human health and the environment. The proposed project is to be carried out by engineering students from Minnesota State University, Mankato (MSU) in collaboration with students at Kwame Nkrumah University of Science and Technology (KNUST) in Ghana as an integral part of our design curriculum.
Expected Results: An easy-to-assemble solar collector kit that can be distributed in Ghana. The proposed solar design will reduce impacts on the environment and directly benefits human health and diminishes resource consumption. The proposed system will be designed for small initial cost (less than $50). It requires no additional long-term cost to operate and maintain.
"Solar Water Heaters", U.S. Department of Energy article on solar domestic water heaters to generate domestic hot water in buildings, explains how solar water heaters work. Solar heat for swimming pools is also discussed.
"Heat-Transfer Fluids for Solar Water Heating Systems", U.S. DOE, describes the types of fluids selected to transfer heat between the solar collector and the hot water in storage tanks in a building. These include air, water, water with glycol antifreeze mixtures (needed when using solar hot water systems in freezing climates), hydrocarbon oils, and refrigerants or silicones for heat transfer.
"Solar Water Heating System Freeze Protection", U.S. DOE,using antifreeze mixture in solar water heaters (or other freeze-resistant heat transfer fluids), as well as piping to permit draining the solar collector and piping system.
"Solar Air Heating" U.S. DOE also referred to as "Ventilation Preheating" in which solar systems use air for absorbing and transferring solar energy or heat to a building
"Solar Liquid Heating" U.S. DOE, systems using liquid (typically water) in flat plate solar collectors to collect solar energy in the form of heat for transfer into a building for space heating or hot water heating. The term "solar liquid" is used for accuracy, rather than "solar water" because the water may contain an antifreeze or other chemicals.
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