Title: A Stochastic Capacity Expansion Model for the UK Electricity System
Speaker: Angelos Georghiou
Affiliation: Department of Computing – Imperial College London
Location: Room 217-218 Huxley Building
Time: 5:30pm
Abstract. Energy markets are currently undergoing one of their most radical changes in history. On one hand, market liberalisation leads to a shift from state-owned utilities with a focus on failure resilience towards competitive markets where reliability is traded off with costs. This will result in a much higher utilisation of generation and transmission facilities, which in turn leads to a less predictable system behaviour and more frequent outages. Moreover, predictions about climate change dictate the gradual replacement of non-renewable energy sources with renewable alternatives such as solar or wind power. Contrary to non-renewable energy, the electricity delivered from renewable sources is highly uncertain due to the intermittency of solar radiation, wind etc. Both developments highlight the need to accommodate uncertainty in the design and management of future energy systems. This work aims to identify the most cost-efficient expansion of the UK energy grid, given a growing future demand for energy and the target to move towards a more sustainable energy system. To this end, we develop a multi-stage stochastic program where the investment decisions (generation units and transmission lines that should be built) are taken here-and-now, whereas the operating decisions are taken in hourly time stages over a horizon of 30 years. The resulting problem contains several thousand time stages and is therefore severely intractable. We develop a novel problem reformulation, based on the concept of time randomization, that allows us to equivalently reformulate the problem as a two-stage stochastic program. By taking advantage of the simple structure of the decision rule approximation scheme, we can model and solve a problem that optimises the entire UK energy grid with nearly 400 generators and 1000 transmission lines.
About the speaker.