Microgrid Designed by Pitt Engineers Drives Clean Energy at Trucking Facility

At first thought, the topics of clean energy and trucking might seem to be antithetical.

However, a trucking facility about 13 miles northeast of the University of Pittsburgh is bringing the two together by running on clean, renewable energy thanks in part to Pitt’s Swanson School of Engineering.

All amenities in the docking terminal of PITT OHIO’s Harmar facility — including lights, electric forklifts, computers and battery chargers — operate from power supplied by an on-site microgrid. Designed by Pitt’s Gregory Reed and a cohort of graduate students, the microgrid consists of about 180 solar panels, a 38-foot-tall wind turbine and battery storage, all integrated through a novel direct current (DC) architecture.

The wind turbine is planned to have a 20-foot addition to its structure and a second turbine scheduled to be installed, which will allow the microgrid to store up to 70 kilowatt hours of renewable energy.

“A microgrid – which you can think of as a power ‘island’ within the larger commercial grid – can provide a more sustainable, reliable and cost-effective generation and distribution network for a system as small as a home to as large as a city, or, in this case, a commercial trucking enterprise,” said Reed, director of Pitt’s Center for Energy and the Energy GRID Institute. “This is a really successful project from lab to deployment and has exceeded both our expectations and PITT OHIO for such a novel endeavor.”

Reed and his team are also aiding in the design of the mid-Atlantic and Midwest transportation service company’s second microgrid in Parma, Ohio, providing the engineering design, development and concept of the project, and informing and managing the project team.

Reed said microgrids offer advantages over conventional utility-supplying methods in several areas, including resiliency, reliability, security, sustainability and economics.

“It really depends on your priorities as an organization,” he said. “But you can take any one of those five reasons to justify a microgrid or some other form of renewable energy source for your facility. Every one of these reasons is becoming more of a justification to make this commitment.”

The main area powered by the microgrid is the terminal, where between 200 and 250 trucks load and unload each day with 100 loading docks available for use.

“We used to go through these lights (by each dock) about once a day before the grid and using conventional lighting,” said Jim Maug, director of building maintenance and properties at PITT OHIO. Now, he said, “we haven’t been able to burn one of these (lights) in two and a half years.”

If the area were to experience a power outage, the microgrid would function independently and enable operations to continue unabated.

“This is not what you think a truck terminal would be like,” Maug said.

Reducing the Carbon Footprint

The installation of microgrids at the PITT OHIO facilities continues the company’s commitment to sustainability that began with building solar panels several years ago for its East Windsor, New Jersey, location, which create 100 percent of the energy consumed there. Other examples, all at the Harmar facility, include replacing traditional sinks with touch-free faucets; installing carpeting and storage lockers made from post-consumer recycled materials; planting a community garden that produces several kinds of vegetables; and purchasing about 30 trucks powered by natural gas.

The Parma location’s microgrid will be about 10 times larger than Harmar’s and enable the facility to use direct current DC in generation, transmission, distribution and use. A DC microgrid is more efficient and cost-effective than the legacy AC-to-DC conversion used today in electric transmission and distribution, since most power electronics technology operate on DC, said Reed.

“When you look at elements that are producing energy in this system, solar, batteries and wind inherently use direct current conversion,” said Reed. “LED lights, electric vehicle chargers, electronics and so much of what we use today use direct current infrastructures, and so eliminating the need to convert from one state to another is a tremendous advantage.”

Because of these investments, the company was issued LEED Gold certification by the U.S. Green Building Council in 2017.

“We’re taking things we’ve done in the past and improving upon them,” said Jim Fields, chief operating officer at PITT OHIO. “The Swanson School has given us the direction for all future plans with their software to help us determine how many solar panels we need or how many wind turbines make sense for a location, based on what we want to service with renewable, sustainable energy.”