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They incite investments in renewable energy sources (RES), can improve the integration of RES into the energy system, and empower local communities. However, as electricity is a low involvement good, residential households have neither the expertise nor do they want to put in the time and effort to trade themselves on their own on short-term LEMs. Thus, machine learning algorithms are proposed to take over the bidding for households under realistic market information. We simulate a LEM on a 15 min merit-order market mechanism and deploy reinforcement learning as strategic learning for the agents. In a multi-agent simulation of 100 households including PV, micro-cogeneration, and demand shifting appliances, we show how participants in a LEM can achieve a self-sufficiency of up to 30% with trading and 41,4% with trading and demand response (DR) through an installation of only 5kWp PV panels in 45% of the households under affordable energy prices. A sensitivity analysis shows how the results differ according to the share of renewable generation and degree of demand flexibility.<\/jats:p>","DOI":"10.1186\/s42162-021-00141-z","type":"journal-article","created":{"date-parts":[[2021,5,25]],"date-time":"2021-05-25T16:03:08Z","timestamp":1621958588000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Reinforcement learning in local energy markets"],"prefix":"10.1186","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1591-3729","authenticated-orcid":false,"given":"Samrat","family":"Bose","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Enrique","family":"Kremers","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Esther Marie","family":"Mengelkamp","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jan","family":"Eberbach","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christof","family":"Weinhardt","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2021,5,25]]},"reference":[{"issue":"11","key":"141_CR1","doi-asserted-by":"publisher","first-page":"1989","DOI":"10.1016\/j.epsr.2008.04.002","volume":"78","author":"MH Albadi","year":"2008","unstructured":"Albadi, MH, El-Saadany EF (2008) A summary of demand response in electricity markets. 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