This document discusses a system designed to increase the efficiency of concentrated solar power generation. The system uses a parabolic trough solar concentrator and heat exchanger to capture waste heat from a solar panel. By focusing sunlight and transferring heat to a working fluid, the system aims to utilize more of the solar energy than traditional photovoltaic panels alone. An experiment will track system temperatures and solar input to calculate the overall efficiency gained from combining thermal and electrical energy collection. The results could demonstrate a six-fold increase in energy captured through cogeneration compared to photovoltaics alone.

1. Increasing Concentrated Solar Efficiency
using Thermal Cogeneration
Solar power represents a fast-growing, environmen-
tally conscious industry. Concentrated PV systems focus
the power of the sun onto a small area, usually a strip or
a spot. Silicon solar panels convert approximately 15%
of solar energy into electricity, while the rest is lost as
waste heat. We have designed a concentrator, heat
exchanger and thermal storage system to operate with a
pre-made “strip” type solar panel.
We present a solution to capture waste heat from a
low concentration solar panel with the goal of increasing
overall system efficiency. We have designed and
produced a parabolic trough solar concentrator and a
tube-and-fin heat exchanger to meet this goal. We select-
ed equipment and materials to maximize return on in-
vestment with a keen interest in reducing manufacturing
and assembly time.
An experiment has been devised which tracks system
temperatures, solar radiation and other environmental
factors to calculate overall system efficiency.
• Increase the system efficiency (utilize wasted energy, calculated as a ratio
by output divided by input)
• Determine the best materials for the parabolic reflector (calculated by
cost, weight, durability divided by each material’s respective output)
Energy from the suns hits the earth at a concentra-
tion of 1000W/m2
.Our system has a 1.32 m2
collection
area, so a maximum of 1320 Watts could be collected if
the system were 100% efficient. We will calculate system
efficiency by measuring the combined thermal and elec-
trical energy captured by the system,
This solution represents a fusion of Concentrated
Photovoltaic (CPV) and Concentrated Solar Thermal
(CST) systems.
Mechanical
Construction of
Concentrator
Heat Exchanger
Panel Brackets
Optical Analysis
Fluid Mechanics
Electrical
System Wiring
Sensor Selection
Circuit Analysis
Charge Controller
Tracker Design
Battery Config.
Materials
Metals Selection
Adhesives
Fluids Analysis
Thermodynamics
Thin Films
Samples Testing
Alex Bishop, Mike Durr, Daniel Meiselman and Liku WakaConcentrated Solar
The concentrator reflects the sun’s rays toward the solar panel
Collaboration of
Engineering Concentrations
Objectives
1. Study and design a concentrated cogenerated PV system.
2. Develop a mathematical model and simulate the experimental system.
3. Design and execute a controlled experiment to measure system efficiency.
Concentrator is supported by a portable structure. Lower render details angle selection lever
Various manufacturing and assembly photographs from CPV project
Many thanks are due to Dr. Orguz Soysal, Dr. Mohammed
Eltayeb, Dr. Julie Wang, Duane Miller and Steve Bevin.
Their time and assistance are greatly appreciated.
Method
To calculate theoretical system efficiency, we must
assume several operating variables including flowrate,
surface temperature, inlet temperature and heat rate.
The heat exchanger fluid is heated by internal convec-
tion. By assuming constant surface flux along the sur-
face, we can calculate a heat exchanger effectiveness and
fluid outlet temperature.
References
1. Incropera, F. & Dewitt, D. (2012)Fundamentals of Heat and Mass Transfer. 7th Edition.
2. Burns & McDonnell (2009). Concentrating Solar Trough Modeling: Calculating
Efficiency. TECHBriefs, No. 4.
3. Kalogirou, Soteris A. (2004) Solar thermal collectors and applications, Department of
Mechanical Engineering, Higher Technical Institute, Cyprus
4. Li, L., Kecskemetly, A., Arif, A., & Dubowsky , S. (2010). Optimized Bonds: A New
Design Concept for Concentrating Solar Parabolic Mirrors.
5. Meyer-Arendt, Jurgen R. (1995) Introduction to Classical and Modern Optics.
6. Alves, L. and Boling, N. (2010). Novus Today. High-Efficiency Solar Coatings.
7. Forristall, R. (2003) Heat Transfer Analysis and Modeling of a Parabolic Trough Solar
Receiver Implemented in Engineering Equation Solver. NREL
Conclusion
Under equillibrium conditions, the outlet temperature is
expected to be 1.3°C higher than the inlet temperature.
We expect the system will collect 660 Watts of thermal
energy and produce 80 Watts of electrical power. The rat-
ed power of the solar panel is 106 Watts, so if experimen-
tal data matches our predictions, six times as much energy
will be collected through cogeneration as compared to PV.
Outcomes
System temperatures will converge in log decay, then steadily increase