Knoy Hall of Technology is now generating a portion of its own electricity via solar photovoltaic arrays on its roof. It is the first building on Purdue’s academic campus to have this capability.
"We have grid-tied the solar panels to Knoy Hall which allows the building to use the generated electricity," said Terance Harper, a graduate student in mechanical engineering technology. "If there is an excess, it will be pushed to Purdue’s electrical grid."
The panels have been tied to the grid since Oct. 30. Its set-up is configured to handle 10 kilowatts of generated electricity. The current array can generate three kilowatts, which means researchers hope to expand its capabilities. Knoy Hall has had the current photovoltaic installation since 2000. The energy it previously generated was sent to batteries and then used for pumps and fans in certain labs.
The project has been funded by the College of Technology's Center for Technology Development (CTD). The industry partners for CTD are interested in testing solar power as a possible back-up system for their manufacturing facilities around the world where a continuous electricity supply is not always guaranteed. And in the United States, using solar energy to lower peak time usage from the electric grid could save companies significant amounts of money.
Harper is using the solar energy research as part of his master’s thesis. He is studying the use of microgrids as a way to improve energy efficiency in a manufacturing setting. The solar set-up at Knoy Hall is not a microgrid yet because it can’t be shut off from the electricity grid and operate the entire building on its own. But Harper’s work will include writing a program to help control the systems in the Applied Energy Laboratory that use electricity (heating, ventilation, air conditioning, pumps and fans) to improve the efficient use of electricity that is generated on site.
Phase 2 of the project will include expanding the size of the array so it can produce 10kw and including electricity storage options to bring the building closer to operating as a microgrid.
The array can be beneficial for students and other researchers, too. Students in the Department of Building Construction Management will gain first-hand knowledge of how a PV array operates and how it is installed before they incorporate one into their design projects. In the Department of Mechanical Engineering Technology, the energy systems classes will benefit from examining a working solar PV array. And smart grid researchers in the Department of Electrical and Computer Engineering Technology will be able to use the real-time data for their analyses.
The education doesn’t stop in the classroom, either. Because this was the first installation on Purdue’s campus, the installers also had to learn about the systems and the codes required to ensure the installation is safe and works properly. In fact, building construction management graduate student John Zimmerman and Brian Loss, clinical assistant professor of building construction management, have written an academic paper about the electrical codes for PV systems and the ways they can be interpreted.
“We demonstrated that we can comply with code, that we can put together a system that is satisfactory to the most critical observer,” Loss said. “It was good for the industry and good for the next project. There were a number of technical issues where the code is ambiguous or contradictory. This set a benchmark for future installations here and elsewhere.”
Additional collaborators for the projects are Bill Hutzel, professor of mechanical engineering technology, Athula Kulatunga, professor of electrical and computer engineering technology, and Chris Foreman, assistant professor of electrical and computer engineering technology.
Anyone can view online how the system is performing. The Web interface shows the photovoltaic array’s ability to generate electricity throughout the day, providing real-time and historical data.
(Photo: Terance Harper and Brian Loss show off the current solar PV array on the Knoy Hall roof.)