NEK wants to install a total of 280 MWh of batteries at several hydro power plants

Bulgaria’s National Electric Company (NEK) is boldly moving towards batteries and is already considering installing energy storage systems at several hydroelectric plants (HPPs). For this purpose, the company is conducting a market consultation, published a few days ago on the Public Procurement Agency (PPA) portal, with no set deadline.

The company's ambitions are to equip four hydropower plants with electricity storage systems with a total storage capacity of nearly 280 MWh.

One battery each with a capacity of 101.52 MWh and a nominal power of 30 MW is planned for the Aleko HPP and the Studen Kladenets HPP. Facilities are required to have a minimum discharge/charge time of 3 hours, calculated as the minimum number of hours the facility can discharge/charge in continuous operation while maintaining its rated MW capacity.

For the Devin HPP, the plan previews a battery with a capacity of 56 MWh and a nominal power of 25 MW. It will need to have a minimum discharge/charge time of 2 hours.

At the Topolnitsa HPP, the idea is for the system to have a total capacity of 20 MWh and a nominal power of 10 MW. The facility will have a minimum discharge/charge time of 2 hours.

At the moment, the state-owned NEK does not have such storage facilities, but it is striving to build a system that will be connected to the electricity transmission network.

In September, NEK started a pilot project for installing a battery at the Vacha 1 HPP by launching a call for the construction of the infrastructure and the supply of the system worth 3.4 million euros. It has generated great interest - 11 participants submitted an application, and the proposals are currently being evaluated. These are the candidate companies: CERB, Koem Group, Solarity BG, Electricity EOOD, ATP-Atomtoploproekt, Telelink Infra Services, Briabuild-Solar, R&G Projects, GBS - IPS (GBS Energy Solutions, Solar G, International Power Supply), Mega El, and NRG Soft.  

The idea for the batteries is to operate entirely on a market principle - charging the batteries during the hours with low electricity prices on the Bulgarian Independent Energy Exchange (BNEB) and discharging them accordingly during the hours with high prices. NEK expects to profit from the price difference.

Translated by Tzvetozar Vincent Iolov