July 27, 2023 |
Photo – Map of proposed Seminoe Pumped Storage Project – Courtesy seminoepumpedstorage.com
RPlus Hydro provided the county commissioners with an update on their Seminoe Reservoir electrical storage system.
RPlus Hydro, a subsidiary of rPlus Energies, is a renewable energies provider out of Utah specializing in pumped storage hydropower projects. Pumped storage is a way to stockpile electrical energy using water and gravity. Water is pumped from a lower body of water to another lake situated at a higher elevation. When demand for electricity exceeds the supply, the higher body of water is allowed to drain down into the lower lake through a turbine. The water, pulled by gravity past the turbine, creates electricity.
At the July 17th Board of Carbon County Commissioners meeting, RPlus Hydro Program Manager Lars Dorr explained the project. Dorr said the upper reservoir would be built in the mountains northeast of the Seminoe Reservoir.
Dorr said his company chose the Seminoe Reservoir because of the preexisting lake. Dorr said water from the upper lake will drop 1,000 feet through a large pipe to turn a turbine and generate electricity.
Commissioner John Johnson asked Dorr how large the upper reservoir would be. The program manager said the lake and all the surrounding infrastructure would be around 160 acres.
Dorr said the upper reservoir was expected to generate nearly a gigawatt of electricity for approximately half a day. The program manager said the power would travel around 30 miles through Carbon County to reach Pacificorp’s Aeolus electrical substation near Medicine Bow.
Dorr said the Seminoe Pumped Storage Project was expected to cost two and a half billion dollars.
Commissioner Johnson asked if the price included building the electrical transmission lines to Medicine Bow. Dorr said yes. The program manager said the power lines would run along existing Western Area Power Administration lines.
Dorr said the pumped storage project will help Wyoming maintain its role as one of the country’s energy leaders. He said the project will employ several hundred people during construction. Dorr said the electrical storage system will require around 30 people to maintain.
Dorr said construction of the project was estimated to produce around $60 million in sales tax. Afterwards, Dorr said the completed electrical storage system would provide Carbon County with approximately $8 million a year in additional taxes.
Commissioner John Espy asked Dorr what impact, filling the upper lake, would have on the Seminoe Reservoir. Dorr said the water level could drop anywhere between half a foot to nearly two feet, depending on the amount of water in the Seminoe Reservoir.
Dorr said it would take about 15 hours to fill the upper reservoir if it was completely drained.
Dorr said the power generation equipment would be located about 1,200 feet beneath the upper reservoir.
Dorr said the project is far from completion. He said his company needed to complete environmental studies required by various state and federal agencies, some of which will take several years. Dorr said he hopes to have the final Federal Energy Regulatory Commission and National Environmental Protection Act authorization by the beginning of 2026. The program manager said construction wasn’t expected to begin for another year after that.
Dorr said RPlus Hydro has many more hurdles to overcome before any physical work can begin on the Seminoe Pumped Storage Project. He said he will visit the county commissioners at least once a year to provide updates on his progress.
