Report lists three options for upgrading Coos transmission loop

GROVETON— A just released report presents three options for upgrading the electric transmission system in Coos County at price tags ranging from $165 million to $210 million.

Mandated by Senate Bill 140, the report was prepared by the N.H. Public Utilities Commission. 

Presenting the report at last week’s meeting of the Groveton Regional Economic Action Team, PUC Senior Policy Advisor Michael Harrington warned the cost figures are rough since no detailed engineering analysis was performed. 

“They’re only estimates at this point,” he stressed.

The existing 115-KV line in Coos County can only handle an additional 60 megawatts of power. That figure could be increased to 100 megawatts with some minor upgrading of the line. But handling more than 100 megawatts will require a major upgrade. 

Developers proposing over 400 megawatts of wind and biomass projects in Coos County have applied to connect to the system. That does not include Laidlaw Energy’s proposed 60-megawatt biomass project for the former Berlin pulp mill property. Laidlaw has not yet filed with ISO-NE, the not-for-profit organization that operates the power system in New England. 

Coos economic development officials are looking at renewable energy generation facilities, especially biomass plants, as a way to revive the economy of the North Country. 

Under the current system, projects are considered in the order in which they apply to the ISO-NE’s so-called queue. First in the queue from Coos County are two wind projects proposed by Noble Environmental Power. The first is a 100-megawatt wind farm in the Phillips Brook watershed that the company expects to get on line in 2009. The second Noble project is a 140-megawatt wind farm in an undisclosed location.

Noble’s Phillips Brook project would use up all the available capacity in the Coos loop and require the company to cover the estimated $10 million cost of the minor upgrading to handle the full 100 megawatts. 

Adding additional generation beyond the first wind farm to the Coos loop would be an expensive proposition. Paying for that upgrade is a major sticking point. 

The Coos transmission loop runs between the Whitefield, Lost Nation (in Groveton), and Berlin substations and is owned by Public Service of N.H. A 115 KV line connects the Whitefield substation to the regional system at National Grid’s substation at Moore Dam in Littleton.

The report lists three options for upgrading the PSNH and National Grid systems to accommodate 400 to 500 megawatts of additional power. All three would use the existing system’s right-of-way.

* Option 1 would replace the entire 73-mile loop with a higher capacity line as well as upgrading a portion of the line from Whitefield to Littleton. The estimated cost of Option 1 is $210 million. It would allow new generation to connect anywhere on the loop.

* Option 2 would construct a new line from Whitefield through Lost Nation to Dummer. The line would accommodate Noble’s wind farm at Phillips Brook, freeing up 100 megawatts of transmission capacity on the Berlin to Whitefield line. It would still require upgrading the line between Whitefield and Moore Dam. The estimated cost is about $170 million. The option would somewhat limit locations for new generating facilities.

* Option 3 would construct a higher capacity line between Littleton and Dummer. Noble’s wind farm project at Phillips Brook would transfer to that line, freeing up 100 megawatts of capacity in the existing loop. The estimated cost of the option is $160 million. It would somewhat limit locations for new generating facilities.

The report also suggests an interim measure that would upgrade the loop by the 100 megawatts to accommodate the Nobel wind farm. Additional generators would be allowed to interconnect while upgrades were being made, even if transmission capacity did not exist all the time. The report noted such an arrangement would limit the output of such power plants, which might make the option unacceptable to the generators and their investors.

Then there is the issue of paying for the upgrade of the loop.   

Under the current system, developers are responsible for paying the cost of any transmission upgrades necessary to connect their facility to the grid. No mechanism exists to pro-rate the cost among future users and upgrading the Coos loop does not qualify for regional cost sharing through the ISO-NE grid. 

Once the capacity in the Coos loop is used up, the entire cost of upgrading the system falls on the next developer to go on the loop. 

“Everyone realizes something different has to be done,” said Harrington.

The report proposes a possible scenario to cover the cost of upgrading the Coos transmission system that would require generators to pay a pro rated share of the total costs. It also calls for ratepayers to pay the cost for surplus capacity with suggestions for funding sources. Enacting the funding scenario would require legislation and a commitment from the generators.

Even then, Harrington conceded it is a multi-step process with studies and state and federal reviews involved. Once an option is selected and approved, the report notes designing and constructing the upgrade could take three to five years.

The report points out the issue is not unique to New Hampshire. Other states face similar challenges. Renewable energy generators tend to be small and facilities must be built where the fuel source is located. In many cases those locations are in rural areas away from population centers where most large generating stations are sited.

The report recommends reconvening the Northern New Hampshire Electricity Transmission Upgrades Ad Hoc Working Group initially established by state Senator Martha Fuller Clark. It suggests the group use the data collected to develop detailed proposals to present to the legislature. 
(A copy of the Background Report on N.H. Transmission Infrastructure can be found and downloaded off the PUC’s website at

Source: http://www.coosconversation...

DEC 10 2007
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