UD researchers and utility employees join to discuss solar power integration issues
8:40 a.m., April 2, 2014--Solar technology currently makes up about one percent of the energy market in the U.S., but it’s growing rapidly and in 2013 was the second largest source in capacity added.
On Thursday, March 20, a group of researchers from the University of Delaware met with the solar application team from Pepco Holdings Inc. (PHI) to discuss some of the unique challenges associated with integrating solar power into existing energy systems.
Peering into cell structures
Hosted by UD’s Institute of Energy Conversion (IEC), the collaborative learning session was organized by Josh Cadoret, who earned his master’s degree in energy and environmental policy at UD and now works for PHI.
“I thought it was important for our team at PHI to learn more about photovoltaic solar cell technology and installation and beneficial for UD faculty and students to learn about how the widespread growth of PV is affecting the utility industry,” said Cadoret, who evaluates and approves customer applications for connecting their solar systems to the grid.
About 20 PHI employees from New Jersey, Delaware and Maryland, along with some 20 students, faculty, and research staff from UD interested in the interface between the smart grid and PV energy generation, attended the full day of presentations. Several employees of the city of Newark Electric Department also joined the group.
Solar brings about paradigm ahift
Steve Steffel, manager of Distributed Energy Resources and Planning at PHI, gave a morning seminar, “Connecting Solar to the Grid -- PHI Perspectives.”
PHI serves about two million customers across an area that spans more than 8,300 square miles. Through the company’s Green Power Connection, customers can install renewable-powered generators, enabling them to draw energy from the grid when needed and to send energy back to the grid when their systems produce more than they use.
Steffel explained the paradigm shift that occurs in the utility industry as solar is added to the mix. In contrast to traditional systems, which rely on large centralized power plants, many small- and medium-scale solar generators are now distributed across the grid that are outside of direct utility control.
“Solar is a disruptive technology in that it changes the paradigm of the typical energy sources and significantly alters the flow of power on the grid,” Steffel said. “The solar customer is still connected to the grid and, in many ways, puts even more demand on grid resources than the traditional customer.”
Accommodating this shift will require a new financial approach, processes to streamline customer applications, bigger data to control distribution systems, and advanced modeling systems for forecasting, planning, and balancing load. Collaborative efforts are aimed at addressing both technical and customer service issues.
“We all have to work together to create smart energy,” said Steffel. “Success will be based on smart grids, smart inverters, and smart premises.” The latter will include elements like smart thermostats, smart appliances, and remote access and controls.
Solar energy production on the rise
In the afternoon, Steve Hegedus, senior scientist at IEC and associate professor in the UD Department of Electrical and Computer Engineering, gave a tour of the IEC’s Solar Module Museum followed by a presentation, “Photovoltaic Solar Cell Trends, Technology and Applications.”
IEC is the oldest solar research facility in the world and has produced many professionals working in the field, Hegedus said.
In the past three years, IEC has worked with more than 30 companies across the U.S. and internationally to develop such products as solar cells on glass, flexible solar cells and interconnected solar mini-modules using materials ranging from crystalline silicon to cadmium telluride. The institute also works with industry to do accelerated time testing on solar cells, which are expected to last 25 years or more.
Hegedus, who was the first resident of Newark, Del., to install a rooftop solar photovoltaic system, pointed out that solar energy production is on the rise globally. The total amount of photovoltaics installed currently in the world is about 100 gigawatts and 39 of those gigawatts were installed in the past year alone.
“We now have the PV capacity of 100 nuclear or coal-fired power plants,” Hegedus said.
The growth rate for jobs in the solar industry was 10 times higher than the average U.S. job growth rate during the past year, Hegedus said, noting that “prices have fallen phenomenally” for the average homeowner interested in installing solar panels 12 percent in the past year alone.
More than four percent of Germany’s energy supply came from photovoltaics in 2013, with solar generating fully 10 percent of that country’s electricity supply last August, Hegedus said.
Still, the quest among researchers is to improve the efficiency of solar cells, to get the most sunlight in and the most voltage out at the lowest cost. Currently, the best commercially available solar modules offer 20 percent efficiency.
While the number of effective full sun hours per day has been calculated for regions of the world Newark, for example, receives 4.6 hours of full sun per day, on average, compared to Miami with 5.2 hours per day what’s not predictable is how much power is available from sunlight because of clouds or hazy skies.
“Minneapolis actually gets more sunlight delivered per month in the summer than Miami due to clear skies instead of haze,” Hegedus said.
At the session’s conclusion, the group discussed several areas for future collaboration, including common interests in monitoring PV performance, integrating PV with the smart grid, and demand-side management.
About the Institute for Energy Conversion
Established at the University of Delaware in 1972, IEC is devoted to the research and development of thin-film photovoltaic solar cells and other photonic devices.
IEC is a totally integrated laboratory focused on fundamental materials and device research carried out in parallel with process engineering studies and analysis of film deposition and processing. This enables correlation of the properties of completed devices with their fabrication, all in the same lab.
Close collaboration between IEC staff and industrial partners ensures that the research is relevant and includes state-of-the-art process development.
About Pepco Holdings Inc.
Pepco Holdings Inc. is one of the largest energy delivery companies in the Mid-Atlantic region, serving about two million customers in Delaware, the District of Columbia, Maryland, and New Jersey.
PHI subsidiaries Pepco, Delmarva Power and Atlantic City Electric provide regulated electricity service; Delmarva Power also provides natural gas service. PHI also provides energy efficiency and renewable energy services through Pepco Energy Services.
Article by Diane Kukich and Tracey Bryant
Photos by Ambre Alexander Payne