Transmission

The U.S. Atlantic Coast is poised to develop well over 100 GW of offshore wind power. This image shows the current and pending Wind Energy Areas (WEAs) along with the Eastern Interconnect (EIC) grid. Note the blue 500 kV lines and the purple 345 kV lines which serve as the arteries of our East Coast grid.

In order to protect our precious coastal environment and make the best use of our existing land-based grid, it is imperative that we develop an offshore transmission backbone with strategically developed landing points. These landing points must accommodate multi-GW scale capacity and benefit the communities they serve.

The U.S. Eastern Interconnect (EIC) has over 90,000 buses. A bus is a node within the electricity grid.

In order to develop transmission expansion planning scenarios that account for electricity demand, variable resource capacity, and cost, it is necessary to develop “reduced-bus” power flow models. This elegant and efficient 300-bus model was created by researchers at Iowa State based on the 90,000-bus EIC model through a process known as Kron Reduction.

While the U.S. has committed to building 30 GW of offshore wind by 2030, transmission development for currently planned projects is proceeding on a project-by-project basis.  While individual states and systems operators are conducting analyses regarding the integration of large-scale offshore wind into their jurisdictions, plans for the system as a whole have yet to be developed. This research is developing transmission expansion planning scenios for 30 GW, 60 GW and 100+ GW offshore wind build-outs using a state-of-the-art reduced bus model for the Eastern Interconnect. These scenarios contemplate the use of advanced HVDC multi-terminal technology, coordination of points of interconnection (POIs) between regions, and the design of optionality for an integrated onshore/offshore grid that can grow with this new U.S. industry and with a future U.S. macrogrid.

Tufts University is pursuing this work in collaboration with Iowa State, Clemson University through funding from the National Offshore Wind R&D Consortium (NOWRDC) and the Massachusetts Clean Energy Center (MassCEC). Our research team is collaborating with the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL).

Through the links provided on this page, you are welcome to access the series of public comments that our Power Systems and Markets Research Group delivered to Massachusetts, New Jersey and FERC in 2020. These activities led directly to our 2021-01 OSPRE report and to our current research described above.