Reliability Modeling with Probabilistic Tools

Brattle has experience evaluating the drivers of resource adequacy risks across many North American markets. For our clients, we have developed custom in-house tools and have also utilized commercially-available software to simulate standard reliability metrics including Expected Unserved Energy (EUE), Loss of Load Expectation (LOLE), and Loss of Load Hours (LOLH) to help our clients make decisions regarding appropriate planning reserve margins needed to achieve reliability standards.

These reliability modeling tools probabilistically simulate the major drivers of resource adequacy risk, including generation outages, weather and other load uncertainty, intertie availability, intermittency of wind and solar generation, and availability of demand-side resources. Our simulations realistically account for market operating procedures, including hourly generation dispatch, import-export scheduling, ancillary services, demand response, and individual emergency procedures. In addition, we often simulate how planning reserve margin decisions affect underlying system economics and costs, including annual production costs, customer costs, market prices, load shed costs, and generator energy margins. A unique feature of our models is the ability to capture flexibility-driven versus reliability-driven reliability events as well as needs for flexible resource requirements, intra-hour price volatility, and expected curtailment levels.

To correctly evaluate the uncertainties we simulate them under the most likely conditions (“Base Case”), a number of sensitivity cases, and a range of planning reserve margin levels. The results for each single case and simulated reserve margin level reflect the probability-weighted outcomes for thousands of full annual simulations.