The paper describes factors influencing the development of electricity storage technologies.
The results of the energy analysis of the electric energy storage system in the form of hydrogen are
presented. The analyzed system consists of an electrolyzer, a hydrogen container, a compressor, and
a PEMFC fuel cell with an ion-exchange polymer membrane. The power curves of an electrolyzer
and a fuel cell were determined. The analysis took the own needs of the system into account, i.e. the
power needed to compress the produced hydrogen and the power of the air compressor supplying
air to the cathode channels of the fuel cell stack. The characteristics describing the dependence
of the efficiency of the energy storage system in the form of hydrogen as a function of load were
determined. The costs of electricity storage as a function of storage capacity were determined. The
energy aspects of energy accumulation in lithium-ion cells were briefly characterized and described.
The efficiency of the charge/discharge cycle of lithium-ion batteries has been determined. The
graph of discharge of the lithium-ion battery depending on the current value was presented. The key
parameters of battery operation, i.e. the Depth of Discharge (DoD) and the State of Charge (SoC),
were determined. Based on the average market prices of the available lithium-ion batteries for the
storage of energy from photovoltaic cells, unit costs of electrochemical energy storage as a function
of the DoD parameter were determined.
The paper presents the results of the energy analysis of the conversion of solar radiation energy into electrical energy in Polish weather conditions. The effect of sunlight and working temperature on the photovoltaic module on its power curve P = f(U) is shown. STC and NOCT conditions are described for which the manufacturers specify the parameters of the photovoltaic modules. The manufacturers of photovoltaic panels should give the PPV = f(E) characteristic for the different values of the operating temperature of the modules. An analysis of the economic efficiency of a photovoltaic power plant investment of 1 MWp taking the current legal regulations for the three variants into account was presented. Variant I – the investor benefits from the support of public aid of operational only, Variant II – the investor benefits from the support of public aid for investment in the amount of PLN 1 million, Variant III – the investor benefits from the support of public aid for investment in the amount of PLN 2 million. For all variants, indicators for assessing the economic effectiveness of the investment and the value of the auction price from the maximum price to the price at which the project loses its profitability are determined.