The German company BE Berlin Economics GmbH, within the “Low Carbon Ukraine” project, funded by the German Federal Ministry of the Environment, Conservation and Nuclear Safety as a part of the International Climate Initiative, conducted a study on possible mechanisms for regulating Ukraine’s energy system in case of a rapid growth of the share of RES with unstable generation mode.
The results of the study are expected to be presented unofficially to representatives of the Ukrainian government in October 2019 and, after approval and finalization, to be submitted as Germany’s official proposal in the framework of the assistance project on reforming the Ukrainian energy sector.
In view of the low level of flexibility of the domestic energy system, the increase in the RES share leads to an excessive load on hydro and thermal generation, which is forced to respond to the unstable generation mode by over-burning of coal and water consumption of hydro-accumulating units. In the summer months of 2019, the so-called “green and coal paradox” was observed, when an increase in the share of RES production required a larger so-called “hot” reserve of coal generation (idle operation of coal power units), which was one of the reasons for insufficient accumulation of coal reserves before the heating season.
In the first half of 2019, over 1500 MWt of new RES capacity was put into operation in Ukraine, which practically exhausted the possibilities of regulating the energy system with coal-fired thermal power stations and hydroelectric power plants, and during periods of maximum generation of green electricity this may lead to the need to shut down nuclear power units with possible negative effects to their reliable operation.
A study conducted by BE Berlin Economics GmbH is considering limiting the generation of RES by the command of the Dispatch Center of the Unified Energy System of Ukraine, which will allow maintaining a stable mode of operation of nuclear generation and minimizing the “hot” reserve of coal thermal power stations. Taken together, this is in line with the objective of the German International Climate Initiative. According to BE Berlin Economics GmbH estimations, the RES limitation will allow to maintain the generation ratio of 57% of NPP, 14% of RES and 24% of TPP. In this case, the maximum amount of electricity that RES will not be able to supply to the energy system will be no more than 17% provided the dispatch control is introduced on the market “a day in advance”.
At the same time, the biggest challenge for Ukraine is to amend the legislation on stimulation of RES, where priority is given to the use of green generation, mandatory payment of the entire amount of electricity generated and compensation for the forced periods of limitation of generation. Thus, there is a need to change the structure of use of funds of the State Enterprise “Guaranteed Buyer”, which will have to pay compensation to the RES facilities owners, but at the same time the share of coal-fired TPPs will be reduced, the stable mode of operation of the NPP will be maintained and the total amount of CO2 and other harmful emissions will be reduced.
