Hydropower

Work moves forward at 100-kW Bell Mill Hydro in New Hampshire

Repairs to Bell Mill Dam at River Street Project No. 4253 (Bell Mill Hydro) in Peterborough, N.H., and installing a new 100-kW small hydropower unit will continue after the Peterborough Board of Selectmen (city council) ordered dam repairs to continue.

Work repairing Bell Mill Hydro and installing the unit were interrupted as the board heard property owner arguments about generating power at the site. The ruling on Nov. 9 ordered the work to move forward.

It is anticipated Bell Mill Hydro will be reconstructed and operating by June 2018. To date, the existing turbine, penstock and generator have been removed in preparation for installation of the new system.

According to a petition before the board, “Although originally a part of various manufacturing enterprises, the dam generated hydroelectric power between 1984 and 2006 pursuant to the current Federal Energy Regulatory Commission (FERC) Exemption held, at the time, by River Street Associates Inc.”

Contoocook Hydro LLC, based in Plainfield, Vt., is overseeing the rehabilitation and modernization at Bell Mill Hydro and will supply the electro-mechanical equipment.

Contoocook Hydro filed a letter on Nov. 23, 2016, informing FERC the exemption from licensing, originally issued May 4, 1982, has been transferred to Contoocook Hydro. The transfer of an exemption does not require FERC approval and Contoocook Hydro is now the exemptee.

In September of this year, FERC ordered repairs to Bell Mill Hydro to bring the project into compliance with its exemption per FERC Accession No. 20170920-3021.

According to submitted documents for the project, the equipment planned for Bell Mill Hydro is a 100-kW variable speed GoHydro turbine. Contoocook Hydro owner, Lori Barg, who also operates the Community Hydro research and development organization out of Vermont, has applied for a U.S. patent for the GoHydro turbine.

The Bell Mill Hydro facility is located in Merrimack County, 12 river miles on the Contoocook River from its confluence with the Merrimack River, about 6 river miles below the U.S. Army Corps of Engineers flood control dam project. The Corps’ Hopkinton-Everett Lakes project provides flood protection to residential, commercial, and industrial property downstream on the Contoocook and Piscataquog rivers, which are tributaries of the Merrimack River.

The total cost for the Bell Mill Hydro project is not immediately available. But, in fiscal year 2017, New Hampshire Public Utilities Commission (NHPUC) awarded Contoocook Hydro a US$173,000 grant to reactivate and modernize electrical components at the project. NHPUC lists the total cost for this aspect of the project at $259,250.

The award was remitted from New Hampshire’s Renewable Energy Fund, created from state law in 2007 as a component of the Renewable Portfolio Standard (RPS). RPS law mandates that 24.8% of the state’s electricity come from renewable sources by 2025.

Contoocook Hydro currently operates two additional projects in New Hampshire on the Contoocook River: the run-of-river 250-kW Hopkinton hydropower project, at Hokes Break, which is also exempt from licensing and 600-kW Steels Pond Hydro in Antrim.

Steels Pond Hydro has a concrete dam that has created Steels Pond from the north branch of the Contoocook River. From this project, Contoocook Hydro generates and sells all of the project’s power to the University of New Hampshire through a grid connection. UNH has a tentative agreement to purchase power from Contoocook Hydro via its Bell Mill site once the project is operational.