Energy Storage Facilities System - an electrical installation connected to the unified energy system of Ukraine, which includes at least one electric energy storage facility, including engineering structures, energy conversion equipment and related auxiliary equipment, which selects electric energy in order to postpone its final use to a time later than when it was produced, its conversion into another type of energy in which it can be stored, storage and further conversion of such energy into electric energy for the purpose of its release to the transmission system.
Main technical features that determine the quality and cost of the grid:
Energy capacity - the capacity of the ESF(kWh) or (MWh), equal to the total capacity of the batteries that make up the ESF, and can be released by the ESF to the grid at the point of connection, taking into account the electricity consumption for the ESF’s own needs
Rated power capacity
Depth of Discharge - the maximum permissible level of discharge of the battery of the ESF (exprESFed as a percentage of the nominal energy capacity of the battery), at which the rate of degradation (loss of capacity) of the battery does not exceed the value declared by the battery manufacturer
cycle life/lifetime
state of charge/discharge rate
operating temperature
self-discharge rate
weight
voltage stability
charge cycle
ESF MANUFACTURERS
The use of energy storage facilities (ESF) is possible in the following electricity markets:
primary and/or secondary frequency regulation - ancillary services market and balancing market
purchase and sale of electricity - intraday market, day-ahead market, bilateral contracts market
regulation of imbalances in electricity generation by solar and wind power plants
The ancillary services market is currently the most economically and technically appealing sector for the operation of the ESF.
РAncillary Services Market
The technical features of the ESF allow them to be involved in the AS market for the provision of services as follows:
For 2025, the reserve requirements are as follows:
FСR
primary regulation - frequency support reserve
FRR
secondary regulation - frequency restoration reserve
FCR
99 MW
of loading and unloading, respectively
FRR
Subject to the involvement of renewable energy sources (hereinafter referred to as RES) in regulating and providing reserves, the total capacity of the ESF is required at the level of up to 0,76 GW with technical characteristics that meet the requirements of the Transmission System Code for the frequency restoration reserve. Without the involvement of RES in regulating or unloading NPP capacities during periods of surplus, the need for electricity storage systems may exceed 2 GW.
aFRRs
automatic frequency restoration reserve symmetrically for loading and unloading
aFRRl
automatic frequency restoration reserve for loading
aFRRu
automatic frequency restoration reserve for unloading
The involvement of energy storage facilities will allow to meet the needs for ancillary services at all hours of the day, which will have a positive impact on the quality of services and reliability of the power system.
Ancillary services are provided in accordance with the terms of delivery and volumes specified at SBU auctions.
Marginal Price In The Ancillary Services Market
At the same time, in accordance with the requirements of NCSREPU Resolution No. 1958 dated 30.12.2022, during the period of martial law in Ukraine and until the end of the calendar year in which martial law is terminated or canceled, prices for ancillary services are determined at the level of prices for ancillary services formed for the planning period in the calendar year preceding the year in which martial law was introduced in Ukraine
According to the official website of JSC “NPC Ukrenergo”, the marginal price for SP for 2023 is as follows:
Product
Marginal price (excluding VAT), EUR/MW
FCR
59,47
aFRRs
59,47
aFRRl
43,20
aFRRu
16,26
Taking into account the above, the current marginal price for SP is as follows:
Product
Marginal price (excluding VAT), EUR/MW (taking into account the requirements of NCSREPU Resolution No. 1958 dated 30.12.2022)
FCR
33,82
aFRRs
33,82
aFRRl
24,57
aFRRu
9,25
Connection of BESS to the electrical grid
BESS are classified into five categories:
A1
Connection point with voltage < 110 kV and power ≤ 0.15 MW
A2
Connection point with voltage < 110 kV and power 0.15 MW and ≤1 MW
B
Connection point with voltage < 110 kV and power>1 MW and ≤ 20 MW
C
Connection point with voltage < 110 kV and power> 20 MW and ≤ 75 MW
D
Connection point with voltage 110 kV or higher. BESS also belongs to type D, if its installed capacity is > 75 MW
Terms and conditions for connecting BESS to the electricity grid:
To transmission system (NPC Ukrenergo) can be connected such BESS:
at the 110 kV voltage level with a capacity of > 20 MW
at the voltage level of 110 kV and above, with a capacity of ≤ 20 MW according to the feasibility study
BESS are connected to the distribution systems in accordance with the requirements of the Connection Agreement and the Technical Specifications.
Customers also have the right to connect BESS to their own power grids.
Bonuses:
In case of connection of BESS to the distribution system networks before January 1, 2025, there is no fee for power connection
The construction of BESS can be carried out on land plots of any category of land and/or type of designated purpose
Example of economic performance of a 10 MW/20 MWh ESF
Estimated budget part of the ESF 10 MW/20 MWh project (CAPEX) 7,85 million euros without VAT
№
Initial data for calculation
Value
Unit of measurement
1
Weighted average price of electricity on the DAM
81,33
EUR/MWh excluding VAT
2
The price ceiling for DA 2023 (FСR) for the period of martial law
33,8
EUR/MW excluding VAT
3
TSO transmission tariff
12,2
EUR/MWh excluding VAT
4
Tariff for dispatch (operational and technological) management services
2,4
EUR/MWh excluding VAT
5
Tariff for distribution (II class)
36,7
EUR/MWh excluding VAT
The result of preliminary calculations of the project implementation ESS 10 MW/20 MWh:
Indicator
Value
Value without taking into account the resolution NEURC Resolution No. 1958 dated 30.12.2022
Energy storage facility (ESF) - is an electrical installation where energy is stored.
Energy storage system (ESS) - an electrical installation that includes energy storage equipment, engineering structures, energy conversion equipment and related auxiliary equipment connected to the transmission system or distribution system of electricity or the networks of a power plant or consumer networks for the purpose of electricity extraction, accumulation, conversion and storage of energy, as well as further supply of electricity to the transmission or distribution system of electricity or in the networks of a power plant or in the networks of consumers.
The concept of Battery Energy Storage System (ВЕSS) or Energy Storage is used in European countries and corresponds to the EPS.
