Is the Plateau Creek drainage above McPhee reservoir a good site for a large hydroelectric power plant?
The Dolores Water Conservancy District and an international engineering company are moving to find out if investors are interested.
Tetra Tech, Inc., based in Pasadena, Calif., has completed a 45-page investment-information memorandum for the Plateau Creek Pumped Storage Project.
"It is a document that will be distributed to potential investors to fund a feasibility study," said DWCD manager Mike Preston. "It could be several million dollars to flush out the details, so even that step needs investors."
The District is not funding or building the large project, Preston said, but they contributed $30,000 towards a $130,000 investment information memorandum study. The district holds a feasibility permit for the project from the Federal Energy Regulatory Commission and the water rights needed to support the project. The District is seeking a share of the revenues if the project happens to re-invest in maintenance and improvement of the Dolores Project.
Tetra Tech has evaluated what needs to be addressed in the next phase of the feasibility study, in itself a massive undertaking involving federal and state permits, site engineering plans, environmental requirements, and renewable-energy market research.
The steep, slickrock grade of Plateau Creek where it enters McPhee Reservoir is ideal for a unique type of hydroelectric plant.
Pumped-storage hydro power is an innovative method of creating and selling electricity to meet peak demand loads. The system would require two small reservoirs under 10,000 acre feet to be built on Plateau Creek, one above the other. A pumping system would be installed to deliver water from the lower reservoir to the upper, in essence "charging" the system like a battery
When peak demand on the grid requires extra power, the water from the upper level is sent through a penstock that runs turbines, generating electricity that would be delivered onto nearby transmission lines.
The energy used for the pumping the water back to the upper reservoir would create a net power loss. But the system makes profits by selling electricity to the grid during periods of peak demand when prices are highest.
The market is considered good for this type of hydro-power, and investment for renewable energy projects is on the rise.
Energy companies are potential investors as they expand their portfolios to include green energy. They need supplemental sources to meet demand when the sun does not shine or the wind does not blow.
"Power companies like pump-back hydro because they can call on it when needed to provide power when other renewable energy sources are not producing," Preston said.
DWCD has a legal foothold because it holds the FERC feasibility permit, but it is not an investor in the private sector project. The project is a non-consumptive water system.
The proposed hydro-electric power plant is expected to cost in the $1.3 billion range and would generate 500 megawatts of power.
The district is considering folding into the project a third reservoir long-envisioned for Plateau Creek further upstream.
The 20,000 acre-foot re-regulation reservoir would also be used to store water for delivery to the lower Dolores River for improving fish habitat below McPhee dam.
"The reservoir is called out in the report, and the yield would be devoted to the fish pool," Preston said.