Resumen de Local electricity markets design and operation in distribution power systems
In the context of distributed generation growth, local grids could face operational issues. In that sense, smart grid deployment will give information to local grid operators about grid status at medium and low voltage levels for taking operational decisions on daily basis. This thesis presents local markets as a potential solution to avoid local grid congestions and over-costs. They mainly increase the negotiation power of end-users with distributed energy resources and allow activation of flexibility at local level.
First of all, this thesis analyses electric vehicles as a potential challenge for distribution grids and electricity markets in case of uncontrolled charging as it could cause consumption peaks. At the same time, electric vehicles could be part of the solution thanks to their capability of shifting forward their consumption. The first solution presented in this thesis is a building level electric vehicle management algorithm in order to reduce energy cost and consumption peaks.
However, local grid operators need a solution to deal with aggregated level problems like high demand or high generation periods. Such kind of problems vary over time and place, and they could be difficult to integrate in regular grid tariffs. Therefore, the present thesis provides two local market designs for these problems. The first local market presented is designed for taking advantage of renewable energy producers before and after the whole-sale day-ahead market without threatening distribution grids and increasing the local social welfare. However, this market implies significant regulatory changes because the local market operator should take sorne of the current local grid operator regulated activities.
Therefore, this thesis presents a second market design for managing portfolios of consumers, producers and prosumers, and it could be operated by retailers, balance responsible parties or aggregators for flexibility provision without regulatory issues. The work includes a description of roles, contracts and interactions of such local flexibility market, and three optimization algorithms depending on the application, complexity and portfolio scale. The first algorithm assumes limited information about each site, the second one includes such information but presents potential scalability limitations, and the last algorithm is based on a decomposition method to optimise the aggregator portfolio in a distributed way reducing the computational burden and time.
