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EIA approved for Estonia’s Paldiski scheme

Energiasalv has achieved a major milestone in the development of the world's first underground pumped hydro plant at Paldiski, northwestern Estonia, with the approval of an environmental impact assessment (EIA) for the 500 MW project.

The EIA was approved by the Estonian Consumer Protection and Technical Regulatory Authority on 29 April, clearing the way for the developer to apply for a building permit. “I am pleased that the environmental impact assessment report of the project has been declared compliant and we are on schedule,” said Peep Siitam, CEO of Energiasalv. “The next stage is applying for a building permit, which we want to achieve in the coming months,” he added.

The EIA, which was carried out by local specialized consultancy Skepast & Puhkim OÜ, assessed the environmental impacts of the proposed design of the plant, and the design was prepared by the German engineering consultants Fichtner. The approved EIA report, in conjunction with the plant’s design, is the basis for issuing a building permit for the project, project coordinator Meeli Taveter told H&D. The building permit will in turn define the procurement process, which is expected to be launched this August. Tender documentation is being prepared with Fichtner, with the aim of finding an EPC contractor, although the exact type of contract is still being decided, said Taveter.

In addition to a positive EIA, a life cycle assessment (LCA) of the Paldiski project, which was recently completed by the local consulting company Civitta, demonstrates that the project has a lower carbon footprint compared with alternative power storage solutions. An article giving details of this study appears on our ESG page, see p28. The project, which is to be built at a site near the northern port of Paldiski on the Pakri Peninsula, about 50 km north of the Estonian capital Tallinn, with an initial storage capacity of 6 GWh over 12 hours, is planned to be commissioned by the end of 2029. It will comprise offshore and onshore structures, using the Baltic Sea as an upper reservoir, with an underground reservoir and powerhouse built at a depth of up to 600 m in high strength crystalline bedrock.

The intake structure will be built offshore on an artificial island which will be created using excavated material. The underground structure, as planned in the first phase, will have a total volume of 5.5 ×106 m3, comprising a lower reservoir, the powerhouse, transformer hall and operational areas. The powerhouse, at a depth of 730 m, is designed to be equipped with three 174 MW Francis turbines, so around 520 MW in total.

Full details of the project are given in a paper published in H&D Issue 2, 2021.