EMCAS (Electricity Market Complex Adaptive System) uses a novel agent-based modelling approach to simulate the operation of today’s complex power systems [1]. It is regularly updated and maintained by Argonne National Laboratory in the USA since  2002 [2], and is currently on version 2.6. EMCAS is used by universities, transmission companies, system operators, and power companies in approximately 20 countries, but the exact number of users is not available. Due to the range of users, there are various licensing options available, including educational. To complete a typical analysis using EMCAS requires approximately two weeks of training, and an additional week of training is required to complete an advanced analysis.

EMCAS is used to probe the possible operational and economic impacts of various external events on the electricity sector in an energy system. The analysis is completed on an hourly basis over a user-specified period of time. Market participants are represented as “agents” with their own set of objectives, decision-making rules, and behavioural patterns. Agents are modelled as independent entities that make decisions and take actions using limited and/or uncertain information available to them, similar to how organizations and individuals operate in the real world. EMCAS includes all the entities participating in power markets, including consumers, generation companies (GenCos), Transmission Companies (TransCos), Distribution Companies (DisCos), Demand Companies (DemCos), Independent System Operators (ISO) or Regional Transmission Organizations (RTO), and regulators. All the entities, or agents, interact on several different layers. In the physical layer, the transmission grid is represented on a detailed bus and branch level to allow a full-scale load flow analysis. Here, the system operator dispatches the available generators to meet the load while maintaining the constraints and limitations of the transmission system. The model can simulate all thermal and renewable generation technologies, as well as all energy-storage and electric-vehicle technologies that do not involve hydrogen. Several business layers are used to model the various forward markets (e.g., pool energy markets, bilateral contract market) where generation companies can buy and sell power. On the regulatory layer the user can set various operational and markets rules. EMCAS simulates the operation of a power system and computes electricity prices for each hour and each location in the transmission network. Model results include the economic impacts on individual companies and consumer groups under various scenarios. In early 2007, the capability to analyse power system investments and expansion issues was added using a multi-agent-based profit maximisation approach. The next version will include an additional cost-minimization dynamic programming investment algorithm for regulated markets.

EMCAS has been used in a number reports which are listed on its homepage [2]. These include the analysis of plug-in-hybrids and their effects on the transmission grid [3], a study on the market competitiveness for the US Midwest Power Market [4], simulation of Central European electricity markets [5], short-term electricity market analysis of Iberian system [6], system expansion planning for Iberian markets [7] and Korean markets [8], analysis of Croatian electricity market [7, 9], price forecasting and unit commitment in UK electricity markets, and finally, EMCAS is currently being used to investigate distributed energy in South Korea but this work has not  yet been  published. As stated above, the model is only used to simulate the electricity sector so it has not been applied to a 100% renewable energy-system analysis.


  1. Electricity Market Complex Adaptive System (EMCAS), Argonne National Laboratory, 23rd April 2009,http://www.dis.anl.gov/projects/emcas.html
  2. Argonne National Laboratoty, U.S. Department of Energy, 23rd April 2009, http://www.anl.gov/
  3. Impact of Plug-in Hybrid Electric Vehicles on the Electricity Market in Illinois, Argonne National Laboratory, 11th June 2009, http://www.dis.anl.gov/news/Illinois_PluginHybrids.html
  4. Cirillo, R., Thimmapuram, P., Veselka, T. D., Koritarov, V., Conzelmann, G., Macal, C., Boyd, G., North, M., Overby, T. & Cheng, X. Evaluating the Potential Impact of Transmission Constraints on the Operation of a Competitive Electricity Market in Illinois. Argonne National Laboratory, University of Illinois, Illinois Commerce Commission, 2006, http://www.dis.anl.gov/pubs/56153.pdf.
  5. Botterud, A., Koritarov, V. & Thimmapuram, P., Multi-Agent Simulations of the Electricity Market in Central Europe, Proc. of the 26th USAEE/IAEE North American Conference, Michigan, USA, 24-27 September.
  6. Thimmapuram, P., Veselka, T. D., Koritarov, V., Vilela, S., Pereira, R. & Silva, R. F., Modeling hydro power plants in deregulated electricity markets: Integration and application of EMCAS and VALORAGUA, Proc. of the EEM 2008 – 5th International Conference on the European Electricity Market, Lisbon, Portugal, 28-30 May.
  7. Botterud, A., Mahalik, M. R., Conzelmann, G., Figueiredo Silva, R., Vilela, S. & Pereira, R., Multi-agent simulation of generation capacity expansion decisions, Proc. of the EEM 2008 – 5th International Conference on the European Electricity Market, Lisbon, Portugal, 28-30 May.
  8. Botterud, A., Mahalik, M. R., Veselka, T. D., Heon-Su, R. & Ki-Won, S., Multi-Agent Simulation of Generation Expansion in Electricity Markets, Proc. of the IEEE Power Engineering Society General Meeting, pp. 1-8, Tampa, Florida, USA, 24-28 June.
  9. Fekete, K., Nikolovski, S., Puzak, D., Slipac, G. & Keko, H., Agent-based modelling application possibilities for Croatian electricity market simulation, Proc. of the EEM 2008 – 5th International Conference on the European Electricity Market, Lisbon, Portugal, 28-30 May.