From January 2027, companies connected to high-voltage and very-high-voltage networks are expected to face changes in how they are charged for the use of the electricity grid. The amount of capacity a company reserves and the consumption peaks it generates throughout the month will become more important. The draft price decision published by the Energy Regulatory Office (ERÚ) on 27 October 2026 also provides for relief measures for battery storage facilities and certain electricity generators.

The existing charge for reserved capacity will be replaced by two "capacity-based" components:

• Reserved Capacity: a charge for the capacity made available to the company under its grid connection agreement.

• Maximum Demand: a charge based on the highest average electricity demand recorded over any 15-minute period during the relevant month, after taking into account any applicable relief measures.

Both components will be calculated under two tariff options, T1 and T2. The distribution system operator will automatically apply the option that results in the lower combined charge. Companies therefore do not need to select a tariff in advance.

What charges are set out in the draft price decision? For example, for a high-voltage connection within the ČEZ Distribuce network, tariff T1 provides for a monthly charge of CZK 200,647 per MW of reserved capacity and CZK 20,065 per MW of maximum demand. Under tariff T2, the reserved capacity charge is lower, at CZK 24,401 per MW per month. However, the charge for maximum demand is significantly higher, at CZK 244,011 per MW per month.

A company with a reserved capacity of 1 MW and a monthly peak demand of 500 kW would pay approximately CZK 146,407 per month for these two components, based on the cheaper tariff T2. This amount excludes the cost of electricity itself, other regulated charges and VAT.

Battery storage facilities may qualify for substantial relief. The key factor will be the AKU coefficient, which reflects the ratio of electricity supplied to the grid to electricity drawn from the grid and generated at the shared point of connection. In simple terms, for a standalone battery charged from the grid, the relevant consideration will be the proportion of the electricity drawn that is subsequently fed back into the grid.

Where sufficient electricity is fed back into the grid, the charge for maximum demand may be reduced to zero. For example, in the case of a standalone 1 MW battery storage facility connected to a high-voltage network, with both reserved capacity and maximum demand set at 1 MW, a full exemption would reduce the modelled combined charge from CZK 220,712 to CZK 24,401 per month. The outcome may be considerably different for a battery primarily used to cover a company's own electricity consumption.

Further relief may be available for the actual provision of negative frequency restoration reserve services, for example, where a request is made to increase electricity consumption to help balance the grid. Certain power plants equipped with rotating generators may also benefit from an adjustment to account for their normal technological auxiliary consumption, provided the relevant conditions are met.

The charge for reserved capacity will remain payable even where all available relief measures are applied.

Author: Patrik Müller