Solar + storage at Chesapeake College

By Ben Delman on December 2, 2016

Chesapeake College is developing a combined 1.75 MW solar array and battery storage project on its campus. The solar array is online and the battery storage component is expected to come online in April. Perhaps the most interesting thing about this project is that it almost didn’t happen.

When the college and its partner, SolarCity, first approached Delmarva, a Pepco Holdings International (PHI) subsidiary, with their solar array plans they were told that there was no additional capacity on the grid at their location. Another solar array in the vicinity had taken up all the capacity and no further large-scale solar could be installed without the college paying for expensive utility upgrades to the grid in their area.

This could have meant the end of the project. But, the college and SolarCity worked with Delmarva/PHI engineers to find a solution. The engineers drove the process to find the right technology solution and the right partner to implement it. The creative and collaborative result is a technology solution that can be used again in similar circumstances with other utility customers.

The result was for Delmarva to propose a pilot project with advanced inverters that can receive utility control signals. A battery was also added after the utility, working with AF Mensah, won a grant from the Maryland Energy Administration. The battery will normally operate in the PJM market, the area’s regional electricity grid, and can also provide grid support in the overall distributed energy resources (DER) integration pilot.

The pilot includes an advanced control system that can monitor and control the solar with its advanced inverters, the battery system, flexible load and on the distribution grid, voltage regulation devices and switched capacitors. This pilot will be used to show how each one of these components can operate optimally in an integrated system with increasing amounts of solar.

The battery storage system comes at no cost to the college. A third party, AF Mensah, will own and operate the system. The company will earn income from the system by providing valuable “ancillary services”. This includes frequency regulation to PJM, the regional grid operator. The college will also be able to take advantage of the storage capacity to provide backup power in case of emergency.

The system will be designed as a two building micro-grid. There is also capacity to expand to more buildings in the future. The micro-grid will be able to shut itself off from the utility grid in the event of a power outage. The micro-grid can provide power to refrigerators storing important emergency supplies of medicine and to a 1,000-seat theater that is designated for use as a shelter in an emergency.

Chesapeake College will use the project to provide an on-site example to instruct and educate students involved in the school’s solar energy programs. It will also serve as an example for organizations and municipalities in the area. It demonstrates that renewable energy works and can provide direct economic benefit. Every dollar the college saves on energy costs represents long-term economic value that stays local and strengthens the school’s ability to serve the community.

Project Details:

System size: 1.75 MW (1.5 MW ground mount + 250 kW parking lot structure)
Solar Developer: SolarCity
Storage Developer: AF Mensah
Utility Partner: Delmarva Power
Solar Financing: 20 year Power Purchase Agreement (PPA) with no escalator
Storage Financing: Third-party owned
Expected Savings: $100K/year in energy bills
Goals: Financial savings, meeting the college’s sustainability goals, resiliency, & education