The dramatic turn in the European energy sector after February 2022, linked with a hike in electricity and gas prices, calls for greater efficiency in generation itself, as well as for better use of energy resources. ČEZ has long striven to set an example in this regard: for example, it has reduced its overall energy intensity (i.e., fuel consumption per unit of energy generated) by 10 percent since 2005. It is now stepping up those efforts and is planning a series of cost-saving and optimisation measures in all types of production sources in the coming months. Aside from measures aimed at greater production efficiency, it is also focusing on reducing its own consumption: light bulbs are being replaced in all of its facilities with more efficient LED fluorescent lamps in boiler rooms, machine rooms, as well as in site road lighting, and radiator valves are being replaced, to achieve savings thanks to better heating control. The number of illuminated spaces is being reduced, as is the operation of air conditioners in non-technical rooms, and buildings are being insulated, etc.
“In nuclear power plants, savings are achieved through a series of newly completed as well as planned modifications. One of the recently completed projects is the optimisation of the operation of the pumps for transporting water to the cooling towers in the non-nuclear part of the Temelín power plant, which uses modern methods for the processing of big data, thus improving the cost-efficiency of operations,” said Bohdan Zronek, member of the Management Board and head of the Nuclear Power Division of ČEZ.
At Temelín, it also plans to increase annual production by up to 6,000 MWh, thanks to the recently upgraded block exchanger station in the second block. A similar increase should be delivered by an identical upgrade of the first block planned for 2023-24.
Money is saved by other types of power plants, too. In the steam-gas cycle in Počerady, where the current deployment of less energy-intensive raw water pumps will result in annual savings of more than 240 MWh of electricity, they are thinking ahead. A new turbine deployed on the gas supply and the on-site installation of a photovoltaic plant will make it possible to generate many extra megawatt-hours of electricity per year. The Hodonín Power Plant that generates power from biomass expects significant optimisation in production, thanks to the modernisation of its control system software.
In Tušimice, the renovation of the lighting in the cooling water treatment hall will reduce the consumption in this part of the power plant by at least 20%. The operation of the cooling towers will also be optimised. This will reduce consumption in this energy-intensive section by 0.5%. A whole series of energy-saving measures are being prepared by Energotrans in Mělník in Central Bohemia: for example, the optimisation and regulation of the hot-water heating in the entire complex will be completed within two years. The investment of CZK 12 million will yield annual savings of CZK 6 million in heating costs at the facility.
In the field of renewable resources, in addition to development plans that aim to build new environmentally friendly power plants with a capacity of 6,000 MW, ČEZ wants to look for further optimisation opportunities and reserves in production. The largest volume of internal savings will be delivered by modernised hydroelectric power plants, which are able to convert the same amount of water into a volume of generated electricity up to 4 percent higher, thanks to more efficient operation of new turbine impellers and generators. In terms of large power plants, the Lipno, Slapy, and Kamýk have been completed, and upgrades are in the pipeline for Orlík and Štěchovice.
“This year, we have completed the renovation of the Slapy Power Plant and are planning upgrades of other power plants on the Vltava Cascade and on other Czech rivers. Given favourable climatic conditions, we will gain additional tens of thousands of MWh of emission-free electricity per year. The coordination of the operation of hydropower plants and an optimisation of water energy use were improved by an upgrade of the central control room for hydropower plants. We expect further significant synergies and savings from the upcoming new monitoring centre for all hydro, solar, and wind power plants and other renewable sources,” said Jan Kalina, Member of the Management Board and head of the Division of Renewable and Conventional Energy at ČEZ.
ČEZ sees the main potential in the coming period in the photovoltaic segment. From the one year of the operation of the test plant in Ledvice, it has obtained data on the suitability of individual types of panels, in terms of their deployment in large parks in the future. Efficient deployment of tailor-made panels in the right locales will eliminates losses in production in the order of several percentage points, which, with a capacity of thousands of MW, will result in thousands of GWh of extra emission-free electricity generated. A saving of valuable percentage points will also be achieved by floating photovoltaic power plants, whose properties are being tested by ČEZ in the upper reservoir of the pumped-storage plant in Štěchovice, Central Bohemia. The floating PV installations will help reduce heat losses, especially in summer, and to increase production, thanks to the natural cooling of the panels by the water surface.
Energy plants not only conserve energy, but also valuable raw materials such as water. In 2021, power plants in the Czech Republic saved 50 million cubic meters of surface water and reduced the consumption of drinking water by 18%. ČEZ plans to continue to achieve significant savings of this valuable basic fluid. Millions of cubic meters of water will be saved in its facilities, for example, by cooling tower adaptations that will reduce evaporation of raw water, or by reducing production at coal-based power plants. Another essential point is the recycling of the water which has already been used in the energy industry: by this means, water from cooling cycles leaving conventional power plants lends its power once again to water turbines, for example, in Mělník, Kořensko under the Temelín Nuclear Power Plant, and also in Ledvice, where it drives unique wind turbines. Another type that operates efficiently at low water gradients, a pair of so-called vortex water turbines, is deployed at the small hydroelectric power plant in Želina. Over time, similar solutions will be installed in other energy sector operations.
Examples of ČEZ investments in energy savings and production optimisation:
Temelín Nuclear Power Plant: optimisation of the operation of a pump using a modern mathematical method of big data processing, with the use of operational and meteorological data for the last five years – completion in summer 2022 – saving up to 4,000 MWh of emission-free electricity
Slapy Hydroelectric Power Plant: an overhaul of the TG2 unit – completion in summer 2022 – increase in annual production by 10,000 MWh
Innovative water turbines for low water gradients at the Ledvice Power Plant – completion in summer 2020 – the additional annual production of 3.7 MWh covers the lighting consumption of the Ledvice Wastewater Treatment Plant