The article present results of economic efficiency evaluation of storage technology for electricity from coal power plants in large-scale chemical batteries. The benefits of using a chemical lithium-ion battery in a public power plant based on hard coal were determined on the basis of data for 2018 concerning the mining process. The analysis included the potential effects of using a 400 MWh battery to optimize the operation of 350 MW power units in a coal power plant. The research team estimated financial benefits resulting from the reduction of peak loads and the work of individual power units in the optimal load range. The calculations included benefits resulting from the reduction of fuel consumption (coal and heavy fuel oil – mazout) as well as from the reduction of expenses on CO2 emission allowances.

The evaluation of the economic efficiency was enabled by a model created to calculate the NPV and IRR ratios. The research also included a sensitivity analysis which took identified risk factors associated with changes in the calculation assumptions adopted in the analysis into account. The evaluation showed that the use of large-scale chemical batteries to optimize the operation of power units of the subject coal power plant is profitable. A conducted sensitivity analysis of the economic efficiency showed that the efficiency of the battery and the costs of its construction have the greatest impact on the economic efficiency of the technology of producing electricity in a coal power plant with the use of a chemical battery. Other variables affecting the result of economic efficiency are the factors related to battery durability and fuels: battery life cycle, prices of fuels, prices of CO2 emission allowances and decrease of the battery capacity during its lifetime.

There were done simulations of fuels consumption in the system of electrical energy and heat production based on modernised GTD-350 turbine engine with the use of OGLST programme. In intention the system based on GTD-350 engine could be multifuel system which utilise post-fying vegetable oil, micronised biomass, sludge, RDF and fossil fuels as backup fuels. These fuels have broad spectrum of LHV fuel value from 6 (106 J·kg-1) (e.g. for sludge) to 46 (106 J·kg-1) (for a fuel equivalent with similar LHV as propan) and were simulations scope. Simulation results showed non linear dependence in the form of power function between unitary fuel mass consumption of simulated engine GTD-350 needed to production of 1 kWh electrical energy and LHV fuel value (106 J·kg-1). In this dependence a constant 14.648 found in simulations was multiplied by LHV raised to power –0.875. The R2 determination coefficient between data and determined function was 0.9985. Unitary fuel mass consumption varied from 2.911 (kg·10–3·W–1·h–1) for 6 (106 J·kg-1) LHV to 0.502 (kg·10–3·W–1·h–1) for 46 (106 J·kg-1) LHV. There was assumed 7,000 (h) work time per year and calculated fuels consumption for this time. Results varied from 4,311.19 (103 kg) for a fuel with 6 (106 J·kg-1) LHV to 743.46 (103 kg) for a fuel with 46 (106 J·kg-1) LHV. The system could use fuels mix and could be placed in containers and moved between biomass wastes storages placed in many different places located on rural areas or local communities.