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The Railbelt grid: an expensive need Utilities tell Anchorage task force why the time has arrived to tackle some high-cost upgrades to Alaska’s power-supply artery Alan Bailey Petroleum News
In terms of the priorities facing people in Alaska, the need to upgrade the transmission grid, along with concerns about fuel supplies for heating and power generation, should come second only to declining oil production from the North Slope, Joe Griffith, general manager of Matanuska Electric Association, told the Anchorage Mayor’s Energy Task Force on Nov. 6.
“If we don’t fix these (transmission grid) shortcomings soon, the cost of electricity is going to go up … more, the (cost) savings that are potentially out there will be forfeited and we are not going to ever achieve our alternative energy goal that the state has set for us,” Griffith said, commenting that the current transmission grid is incapable of supporting the anticipated power output from a planned major hydropower facility at Watana on the Susitna River.
As well as heading Matanuska Electric, Griffith is CEO of the Alaska Railbelt Cooperative Transmission and Electric Co., or ARCTEC, a generation and transmission cooperative formed between several Railbelt utilities to collectively coordinate Railbelt energy needs.
Nearly $1 billion The Alaska Energy Authority, or AEA, has recently recommended some major upgrades to the Railbelt grid, with a total price tag of nearly $ 1 billion. But the utilities, having already committed a similar sum of money on essential new power generation facilities, have no ability to raise further debt for work on the grid, Griffith explained.
Although an electricity transmission grid can often be one of the more visible components of a region’s energy infrastructure, the grid tends to be taken for granted along with assumptions that the lights will always switch on and that cell phones can always be charged as needed. But the grid plays a vital role, both in shipping electrons from power stations to electricity demand centers and in enabling electricity companies to juggle the power outputs from different power plants, to balance supply with demand on a minute-by-minute basis, and to ensure the efficient availability of reserve power, should a problem occur at some point on the system.
The Railbelt grid, which has so far enjoyed an exemplary reliability record, is now aging and faces the challenge of some major restructuring of Alaska’s power generation facilities, as new power generation comes on line and aging facilities go out of service.
Bradley Lake One major problem that the AEA plan would address involves constraints on the utilities’ ability to make full use of power from the state-owned Bradley Lake power station in the southern Kenai Peninsula, the cheapest source of power on the grid. This problem, in part a consequence of the state running short of funds before completion of the original Bradley Lake transmission infrastructure some years ago, has become critical as Chugach Electric Association, a major Southcentral utility, phases out the operation of its main power plant at Beluga on the west side of Cook Inlet. Power output from Beluga, an aging plant well past its sell-by date, is in part being shifted to a new power plant in south Anchorage owned by Chugach Electric and Municipal Light & Power.
Chugach Electric currently supplies some Beluga power to Matanuska Electric Association and Homer Electric Association but, with these power supply contracts coming to an end in the next couple of years, Matanuska Electric is constructing its own power station at Eklutna, north of Anchorage, while Homer Electric is implementing new power generation on the Kenai Peninsula.
This re-arrangement of power generation centers will create new bottlenecks for the transmission of power from Bradley Lake through the existing grid.
Griffith said that in the upcoming state legislative session ARCTEC is going to ask for $13 million in state funding for transmission upgrades to start alleviating the constraints on Bradley Lake power. ARCTEC is also asking for $24 million to fund half the cost of a planned increase in the power capacity of the Bradley Lake facility, with the utilities providing the other half of the funding for that project, Griffith said.
Northerly section A major component of the AEA plan consists of $480 million in upgrades to the more northerly section of the grid, the section into which the Susitna-Watana hydropower facility would connect.
Brian Hickey, Chugach Electric executive manager, grid development, pointed out to the Mayor’s Energy Task Force that there will be a timing issue in completing upgrades to the transmission grid to support the Susitna-Watana system. To avoid the impracticalities of trying to shoehorn a series of major grid upgrades into too short a timeframe, oversaturating the Alaska construction market, it will be necessary to start an upgrade program as soon as next year, before a final decision is made on whether to proceed with construction of the hydropower plant, he said.
Efficiency benefits But AEA’s projected benefits from the grid upgrades do not assume that the hydropower plant will be built, Hickey said. In fact, the benefits primarily result from greatly improved efficiency in power generation use, as a robust and flexible grid allows the optimum dispatch of power, making maximum use of the most efficient power generation facilities that are available.
AEA has estimated annual cost savings in the range of $146 million to $241 million if all of its recommended grid upgrades are implemented.
Hickey commented on the importance of viewing the entire grid as a single entity, despite the fact that the grid is operated by six distinct utilities across six different grid sectors: With electrons flowing relatively freely around the wiring of grid, power generation and consumption at one point on the grid impacts power generation and consumption elsewhere. And nowadays utilities commonly buy some power or operate power stations at points outside their own sectors of the grid. At the same time, with Matanuska Electric and Homer Electric about to start generating their own power, responsibilities for balancing the power load across the grid are becoming more fragmented, he said.
This is all happening in a situation where the capacity of the aging grid to transfer power is now being stretched to its stability limits, where infrastructure is in need of replacement and where there is limited interconnectivity between different Railbelt regions, Hickey said.
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