UK demand side flexibility mapped
Open Energi Analyst Remi Boulineau has mapped the UK’s demand side flexibility to reveal 6GW of peak-shifting potential, and 750MW of dynamic flexibility available for real-time grid balancing.
Demand-side response is at its core an optimisation of electricity usage in order to increase the stability of an energy network. The additional flexibility provided by adequate adjustments of energy consumption has major advantages within the context of an energy infrastructure designed to meet occasional peak demands. It represents an already-existing, cheap, sustainable and efficient alternative to building additional generation capacity that is used infrequently.
Flexibility can be defined in different ways, and several of these definitions can also overlap. First we will investigate the peak-shifting flexibility, which we define as the potential for shifting electricity usage for one hour outside of the peak demand of a given winter day. Currently, this is typically a time period where extra generation capacity is needed to ensure Grid stability.
The estimation of the potential peak-shifting flexibility for the GB Grid was obtained by cross-referencing publicly available annual energy consumption datasets with flexibility profiles for domestic and non-domestic users. Open Energi successively manages assets for DSR in the I&C sector, and has developed a large insight knowledge of the associated loads’ flexibility. The installation costs in this sector are around £50,000/MW, which makes it a target of choice for an immediately available and cheap source of flexibility.
While tapping into domestic flexibility might reveal to be slightly more difficult and expensive than for large energy users, we accounted for this sector in order to give a complete sense of the potential size of the flexibility in the country.
The outcome of this analysis reveals that the GB Grid has a peak-shifting potential flexibility of 6 GW, split almost evenly between domestic (3.2 GW) and non-domestic users (2.8 GW). The flexibility results, normalised per area unit in order to identify geographical zones with high flexibility potential, were mapped at a Local Authority level. Unsurprisingly, peak-shifting flexibility correlates with areas of significant electricity usage, namely big cities such as London and areas where energy-intensive industries are present.
This highlights the fact that the development of demand response, along with the improvement of the global energy efficiency in large cities, is a key factor in improving the resilience of the local utility system to cope with peak demand. The ability to shift demand temporally also presents the advantage of being much easier and cost-effective for implementation in urban areas compared to additional generation techniques, such as embedded generation and fuel substitution.
There is a second form of flexibility that can be used to ensure the reliability of an energy network that we will refer to as dynamic flexibility. It consists in a real-time adjustment of power consumption in response to frequency deviation. This frequency regulation activity is a long-lasting opportunity to ensure Grid stability and reliability, and represents a needed enabler to the smooth integration of growing renewables generation sources such as wind and solar.
Our analysis shows that around 750 MW of dynamic flexibility in the non-domestic sector can be unlocked to participate in dynamic frequency regulation activities. This flexibility arises from assets whose power consumption can be shifted, without any consequence for the end user, in order to help balance the Grid at a dynamic scale.
It is important to note that dynamic and peak-shifting flexibilities are not mutually exclusive: an eligible asset fitted with the appropriate equipment can shift its power consumption for either usage. In the following we assume that on a given winter weekday peak-shifting flexibility is used for displacing demand away from the two hours peak (typically 17h.00 to 19.00) into the two subsequent hours, while dynamic flexibility is used during the 20 other hours. We calculated that on a given winter day the potential CO2 savings represents 1560t CO2e per day for peak-shifting flexibility and 3900t CO2e per day for dynamic flexibility.
If we extrapolate the potential CO2 savings of the 750 MW dynamic flexibility operating annually 24h per day this increases to 4860t CO2e per day, and we obtain a figure of around 1.7 million tonnes of C02e saved per year.
Unlocking flexibility means we can build fewer peaking plants, integrate more renewable generation and mitigate the effects of intermittency. It therefore offers major advantages in terms of cost and network reliability and sustainability. Open Energi‘s technology is able to access this flexibility by dynamically and invisibly shifting energy consumption patterns.
 In order to extrapolate the total latent flexibility in the GB Grid, we assumed electricity users that have similar annual energy consumption have comparable flexibility; and contribution to peak demand is correlated to the annual consumption of electricity.