As demand side flexibility creeps from the peripheries to take centre stage in the operation of a net-zero power system, Utility Week asks why recognised barriers to market development are taking so long to break down and unveils a major new initiative to help boost momentum.

The introduction of the Demand Flexibility Service – a dedicated flexibility service for consumers with the appetite and ability to turn down their power usage in response to prompts – in the winter of 2022/23 – was hailed by many as a ‘tipping point’ in the development of energy flexibility in GB, helping to shift it from niche concept to national headline material.

Around 1.6 million households and businesses signed up to National Grid Electricity System Operator’s (ESO) DFS last winter, shifting 3,300MWh of energy demand over the course of a series test events and proving distributed flexibility has a meaningful role in fulfilling system needs.

This winter the ESO predicts the level of flexible capacity to be made available via the DFS to triple to 1GW. This represents promising progress given the ESO will be increasingly reliant on demand-side flexibility to balance a system powered purely by zero-carbon generation by 2035, while also seeking to minimise the costs of decarbonisation through an ongoing affordability crisis.

To help support a cost-effective energy transition the ESO is planning to have a minimum of 4GW of flexibility available from residential and industrial and commercial customers by 2050 – this is based on conservative forecasts from its Future Energy Scenarios (FES) work. As much as 13GW could become available under its more optimistic ‘Consumer Transformation’ scenario.

Indeed, the ESO is already basing its planning for the network on an assumption that flexibility will be reducing peak demand by 15% by 2035. So, while recent progress on activating the demand side potential of consumers should be celebrated, momentum must be sustained and boosted if the ESO’s expectations of between 1.5-7GW by 2035 are to be met – with serious implications for future system operating costs.