After a power failure, the power supply must be restored as quickly as possible. Usually, this is the responsibility of the TSO. Power plants that can start up without an external power supply play a central role in rebuilding the supply.
Many large power plants are thermal power plants. They are able to generate large amounts of electricity but need an external power source to start their electricity production. Without this, neither nuclear nor coal-fired power plants can be put into operation, as there is no energy source for the operation of the cooling and monitoring systems of the reactor and the coal extraction plants.
In contrast to these types of power plants, there are power plants which can carry out a black start. They can start up autonomously and without external energy supply . Power plant types that are suitable for a black start are, for example, hydroelectric power plants, compressed air storage power plants, or gas power plants . Electricity storage facilities are also increasingly being used on a large scale to ensure black start capability.
Operational management means controlling and monitoring of the grid by the network operators. This includes the coordination of ancillary services. The expansion of renewables increases the demands placed on grid operators. Different system services are used for these measures.
The redispatch is a means of grid congestion management - especially in grids with a high share of renewable energies. The TSOs consider the expected feed-in and feed-out at grid level on the previous day. They then use this information to analyze the utilization of the electricity grid. The TSOs use this analysis, also known as load flow calculation , to instruct the power plant operators the day before to postpone the planned electricity production. This avoids foreseeable potential grid bottlenecks. This instruction to shift electricity production is called a redispatch.
The redispatch does not change the amount of electricity fed into the grid, but its local distribution. Meanwhile, there are also pilot projects for the use of renewable energy plants in redispatch.
Feed-in management refers to the regulation of electricity feed-in from renewable energy systems . If sections of the distribution or transmission grid are overloaded and the stability of the grid is threatened, feed-in management comes into play. The grid operator takes renewable energy systems off the grid in the event of a drastic power surplus.
In addition, the provision of electricity without the factual delivery is a popular capacity mechanism. Services of this kind can either be grid reserves or the safety readiness of power plants. This gives these ancillary services a capacity market character. The design of such reserves differs greatly from country to country.
Disclaimer: Next Kraftwerke does not take any responsibility for the completeness, accuracy and actuality of the information provided. This article is for information purposes only and does not replace individual legal advice.
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