Delivery of ancillary services in distribution power systems

One of the technical and organizational challenges the power system faces in deregulated market conditions is to organize an ancillary services market. The growing share of distributed generation of variable (intermittent) energy sources and a change in the market position of consumers, causes the demand for distributed delivery of ancillary services. For this purpose, it is sought to use the ability of the regulatory measures: dispersed generators, consumers, prosumers, and energy storage systems. The most important attempts discussed in the paper were: organizational solutions, i.e. creating balancing groups or virtual power plants; the use of response actions of customers, e.g. in the context of Demand Side Management or Demand Side Response and the search for effective energy storage technologies. Additionally, the role of the Distribution System Operator as the coordinator of ancillary services in a local network was discussed.