February 1, 2018
Vermont

Expert: Holland turbine won’t affect grid

Robin Smith | Caledonian Record | January 31, 2018 | www.caledonianrecord.com

HOLLAND – A large wind turbine on a farm field in Holland won’t overload the grid enough to hurt existing renewable energy producers, according to an expert for the developer.

The Dairy Air Wind turbine of nearly 500 feet tall is planned for a field on Dairy Air Farm off School Road.

The turbine will not cause an unduly adverse impact on the grid, says Dairy Air Wind expert David Estey in recently filed testimony.

And it won’t cost more than is allowed in the Vermont standard offer program under which the developer is seeking state permits, and therefore should be approved, Estey stated.

Experts in electricity generation and the grid operations for Vermont Electric Cooperative, Green Mountain Power and the Vermont Department of Public Service, which is a consumer advocate agency, have stated in testimony that constraints on existing wind power is caused by overloads on transmission lines at certain times.

They have talked about the additional impact another turbine would cause and are seeking to prevent its construction.

In written testimony Jan. 10, Estey, principal engineer at RLC Engineering in Maine, talked about what’s called the Sheffield- Highgate Export Interface (SHEI).

The SHEI monitors flows of electricity between Sheffield and Lyndonville and Highgate to St. Albans, “where power flow limits are established to inhibit voltage collapse following a transmission line outage,” Estey stated.

Generation of electricity can vary a lot because both wind and hydro electric power can be intermittent, he stated.

Vermont Electric Company (VELCO), the company that runs the grid and its transmission lines, indicates in a report that there was more hydro power last spring. That and other factors such as taking equipment off line for repairs at the wrong time prompted the curtailment of existing wind power in favor of hydro power from Quebec, Estey stated.

Estey states that an expert for the department has testified that the Dairy Air Wind turbine would limit existing wind resources in northern Vermont like turbines in Lowell or Sheffield.

But Estey said that the Dairy Air Wind turbine will be outside the SHEI grid area when Hydro Quebec is connected to Vermont.

Estey states that the grid problem existed before the Dairy Air Wind project existed and will be resolved whether or not the turbine is raised.

And he stated that the resolution of the grid limitations in the SHEI area “should not be addressed by declining to honor interconnection access to the Vermont transmission system.” “Developers are not required to reinforce the transmission system to ensure either they or other generators can run at their capacity, ie: to ensure against adversely impacting existing generators’ financial performance.”

Dairy Air Wind received a standard offer contract in 2016 and applied to connect to VEC’s system, Estey said. The system impact study shows that the connection won’t create an adverse impact to system reliability or stability, he stated.

Estey notes that the Dairy Air Wind turbine with a capacity of 2.2 megawatts will provide the most cost-effective electricity to the Holland area because it will be fed directly into the local electric grid.

And he disagrees with an expert with VEC about the cost of producing wind energy from Dairy Air Farm’s turbine.

VEC’s expert Craig Kierny calculates it would cost 13.635 cents/ kilowatt hour – 2 cents more than the 11.6 cents/kwh that the state would accept for this type of turbine project under the standard offer program.

Estey calculated that it would actually be 11.77 cents/kwh, only .17 cents over.