March 05, 2024

Domestic Demand Flexibility in the Great British Electricity System


Centre for Net Zero


We adapted the PyPSA-Eur model to explore the role of domestic demand flexibility in the energy transition. This follows the core assumptions in ESO’s Future Energy Scenarios, combined with insights from the Octopus Energy customer dataset.

The electrification of heating and transport in Great Britain will allow households to provide more flexibility to the grid. This document summarises research that seeks to understand how much flexibility can be achieved, how this flexibility interacts between the two sectors, and how the benefits are spatially distributed. Using a novel linear optimisation model PyPSA-FES, designed to simulate pathways in National Grid ESO Future Energy Scenarios, we model the future power system in Great Britain at high spatio-temporal resolution and integrate demand flexibility from both smart charging electric vehicles and thermal storage-coupled heat pumps. The model then optimises the trade-off between reinforcing the grid to align charging and heating profiles with renewable generation versus expanding dispatchable generation capacity.

Key findings

The modelling shows there are significant system benefits associated with demand flexibility from domestic heat and transport, while providing insights into its role over time and space. Headline findings are:

① By 2030, domestic flexibility can unlock up to 30 TWh of otherwise wasted renewable generation, while reducing distribution capacity needs by 25%.

By 2035, these benefits amount to about £5 billion in savings to the system every year.

EVs have an outsized impact early on: half of the benefits from EV flexibility are achieved in the first 25% of adoption.

④ Demand flexibility helps to optimise grid infrastructure. At distribution level, it reduces build requirements – for example, a reduction of 4.5 GW in Greater London.