Impact of Flexibility Services Implementation on Power Network Constraint Management

The widespread deployment of flexibility services e.g. by generators, energy storage units and demand response, are causing novel challenges to Distribution Network Operators (DNOs) or Distribution System Operators (DSOs) when managing their power systems. The aim of this research is to understand the economic impact that these flexibility services could cause on possible future world scenarios. This paper presents the main findings obtained from the MERLIN project, which explores and compares the techno-economic impact of managing network operational constraints through traditional reinforcement and flexibility services over a ten-year forecast period. Two case studies were carried out, the realistic case (RC), which focusess on realistic load and generation forecasts, and the worst-case (WC), which is what is traditionally performed by DNO system planners to model the impact of peak demand when generation is turned off over a period of time. The analysis was conducted on the 33/11 kV network in Fort William, (Western Scottish Highlands). The study revealed insights into the anticipated costs of traditional reinforcement and influenced when flexibility services would be a more favorable investment option. Results suggest that flexibility services are preferred only to deal with thermal constraints in the 33 kV line, with no or negligible savings in the 11 kV line. The results show discounted savings of around £175k for four year deferral (by 2050), equivalent to 12% of reinforcement costs.