Two Greek municipalities launch pumped storage hydropower projects

The local authorities in Kozani and Voio plan to build and operate matching small pumped storage hydropower plants, while Kozani also intends to pair its facility with a photovoltaic unit, which means it could be turned into a hybrid power plant.

Greece’s efforts to shut down lignite mines and power plants in the region of Western Macedonia and replace them with cleaner solutions are heavily impacting the society there, especially the individuals that work in the dwindling coal industry. However, it is an opportunity for the country’s main coal hub to conduct a comprehensive economic transformation and become competitive with new technologies, helped by domestic and European funds.

Local authorities in the region in Greece’s north, but also elsewhere in the country, are already pushing forward with just transition and innovative green projects. Municipalities are launching projects for solar power plants and other green infrastucture. They are also facilitating the creation of energy communities or cooperatives.

Kozani to combine pumped storage with solar power unit

Kozani, the capital of Western Macedonia, already has a project for the installation of solar power plants with a total capacity of 6 MW. Now it launched a project for a pumped storage hydropower plant of 8 MW, E-Ptolemeos.gr reported. It would be paired with a photovoltaic unit of 8 MW, Mayor Lazaros Maloutas said.

Pumped storage is the oldest and most widespread technology for saving electricity. Such facilities consist of one or more lower and upper reservoirs – lakes. When power demand in the electricity system drops, water is pumped to the upper reservoir so that it can power the hydroelectric turbine when necessary.

Besides its usefulness for storing energy when electricity is cheap and selling it later at higher prices, the technology is necessary to balance the network when weather changes affect renewables production: wind and solar power in particular.

Three locations in play

The local municipal council unanimously approved Maloutas’s proposal to examine the possibility to take out a loan from the Consignment Deposits and Loans Fund of the Ministry of Finance. The mayor revealed three locations are under consideration.

According to the decision, the project’s budget will total EUR 9.5 million. The facilities would be operated by the local authority itself or the Municipal Enterprise for Water Supply and Sewerage of Kozani.

Each of the two reservoirs should have a capacity of 49,500 cubic meters and the difference in their altitudes should be 220 meters. The hydropower plant is envisaged to have two Pelton-type turbines of 4 MW each for the active mode and four 2 MW units for pumps.

The plan reveals both modes should be able to operate simultaneously to enable them to stabilize the network voltage and frequency. The solar power plant is aimed to supply the pumps. The project’s intended storage capacity is 3.5 hours, translating to 28 MWh. The municipality estimated its total annual income at EUR 1.5 million.

Maloutas said financing from the Consignment Deposits and Loans Fund is necessary, alongside other documentation, to apply with the Regulatory Authority for Energy (RAE) for a permit.

Voio municipality already applied for energy permit

Almost simultaneously, the Municipality of Voio, also located in the Kozani regional unit, said it sent an application to RAE for an electricity generation permit for a pumped storage hydropower system of 8 MW. The units would be equivalent to those planned in Kozani.

The site for the project, near the village of Dryovouno, is called Garitsa. It is a former quarry. The space isn’t rehabilitated and it has been an open wound for the area for many years, the announcement adds. It is planned to be used for the construction of two reservoirs with a capacity of 49,500 cubic meters of water each, just like in the regional capital.

The Municipality of Voio said it is the first in Greece to apply for a permit with RAE for pumped storage and clarified that it would own the facility. The local authority estimated project costs at EUR 5.2 million and its annual income at EUR 1 million and added that the Consignment Deposits and Loans Fund would provide financing.

The environmental restoration of the quarry will be an additional benefit, the municipality said.