A Novel Low-Cost, High-Efficiency Solar Powered Micro-CHP System for Electricity, Hot Water, and Space Heating
Developing a novel, low-cost, high-efficiency solar combined heat and power system.
The Regents of the University of California, Merced
Recipient
Merced, CA
Recipient Location
Senate District
27th
Assembly District
$799,363
Amount Spent
Completed
Project Status
Project Result
The project has successfully demonstrated and verified the technical performance of a twenty-tube array solar CHP collector. The solar CHP collector generates 150 WDC electricity and 400 Wthermal per square meter, which can be translated to 205 kWh of electricity and 19 therms of heat and by doing so reduces natural gas consumption (locally and at natural-gas fired power plants) by 40 therms, eliminating 167 kg of CO2 emissions per square meter per year. The system has the potential to save 30% more roof space and $0.29 per watt compared to a system combining conventional solar water heater with solar PV and reduces carbon emissions by $24/Metric ton CO2e.
The Issue
California is faced with the challenge of reducing natural gas consumption to increase safety, reduce greenhouse gas emissions, and enable zero net energy buildings. Solar combined heat and power (CHP) offers the potential to reduce natural gas consumption by providing thermal energy to meet building hot water and space heating needs, while also providing distributed electricity generation. However, current commercially-available solar CHP systems combine traditional PV panel architectures with traditional thermal collector models, limiting cost competitiveness.
Project Innovation
This project developed a novel, low-cost, high-efficiency solar combined heat and power (CHP) system capable of producing electricity for building loads and heat for hot water and space heating. The CHP collector is a modular solar collector which simultaneously generates both heat and electricity at efficiencies comparable to standalone PV and solar thermal systems. The system is packaged in a glass tube and utilizes non-imaging optics for solar concentration, aluminum mini-channels for thermal collection, and commercially available solar cells for electricity production. This reduces the required collector footprint and reduces installation costs, thus providing significant cost savings over existing systems installed side-by-side.
Project Benefits
The unique solar cell/mini-channel interface allows for the collection of thermal energy, while simultaneously cooling the solar cells and enhancing their efficiency. Additionally, the use of various types and efficiencies of solar cells enables the development of arrays that can be tuned for optimal performance in all of California's 16 building climate zones.
Affordability
The solar CHP technology would generate the same amount of electricity (per unit area) as a standalone rooftop PV panel, and also generate a comparable amount of thermal energy as a standalone rooftop thermal panel, while being cost-competitive with either. This would require half the roof space to collect the same amount of energy, significantly reduce installation time and cost, and substantially increase system affordability. Each installed square meter of the novel solar CHP technology would reduce natural gas consumption by approximately 40 therms annually in a typical California building zone.
Environmental Sustainability
Each installed square meter of the novel solar CHP technology would offset 0.28 metric tons of carbon dioxide annually.
Reliability
Increased deployment of solar CHP systems would increase local generation and bolster local system reliability.
Safety
Increased deployment of solar CHP systems would improve safety by lowering natural gas consumption and reducing the amount of natural gas transmitted and stored and the associated risks.
Key Project Members
Ron Durbin
Match Partners
The Regents of the University of California, Merced