Growing Demands on the Grid

At present there are approximately 40,000 Battery Electric Vehicles (BEVs) in the UK, a number expected to rise to between 8-12 million BEVs by 2030, with NGESO estimating this number to increase to 37.4 Million BEVs by 2050. With this increase in energy demand and requirements of the network, there are various unknowns and potential opportunities to be explored.

Potential risk factors ranging from housing diversity, system operation (managing the electricity power system in a safe and efficient manner), and government policy will all affect how the future grid handles the increased capacity as well as the potential for sudden demand increases during different times of the day.

Newer builds will be easier to retrofit with technology that will aid in system operation and help to ensure security of supply for the consumer. However, less than 10% of housing in the UK has been built after the year 2000, with higher rated domestic supply fuses which limit the amount of current that can go into a property. Older properties normally have more limited fuse capabilities and these will need to be upgraded by the DNO. Lack of notification to the DNOs when moving house causes additional problems, especially on the older networks because the DNO can’t detect the clustering of LCT.

System stability and frequency issues, like sudden excursions outside the operational parameters (i.e. within ±0.5Hz from 50Hz), and fault ride through, are all issues that can present a problem, but technology innovation and smart solutions can be put in place before EVs become more widespread.

The team identified four areas where further innovation and collaboration could empower the future grid.

EV & Grid Stability – Priority Areas

1. Grid Visibility – Creating greater visibility of events and customer behaviour across the network.
2. Funding, Incentives, Regulation & Standards – Knowing where and when to invest, within a clear but comprehensive regulatory framework. Increasing levels of new technology will be deployed at lower voltages levels of the grid, exploring how these can affect these frameworks is essential.
3. Flexibility, Transitory Events & V2G – Systems flexibility to defer system reinforcement, potential for incentivised movement of BEV’s for one off events and to opt into flexible V2G services.
4. ESO DNO Communication & Coordination – Bridging the communication gap between the ESO and DSO and DNO networks. Create a system that’s going to be secure, low carbon and affordable.

Samir Alilat, Head of Innovation & Business Development at Kelvatek said: “As more electric vehicles come online, there is essential work to be done to prepare the UK’s grid for the increased requirements of low carbon technology.

“In bringing together Distribution Network Operators, the National Grid and other core stakeholders working on these issues, the roundtable provided a fantastic forum for generating cross-sector recommendations to manage the potential network risks associated with the growth in EVs.

“Moving ahead, Kelvatek will look to build on these recommendations, working in partnership across the sector to deliver innovative technologies which build the resilience and flexibility of the UK’s grid in support of our net zero ambitions.”

If you’re interested in joining these discussions, or potentially collaborating in future projects, please email Samir: s.alilat@kelvatek.com

Summary of Potential Risks

• Housing Diversity – Only 9% of housing in the UK is post 2000 with higher rated domestic breaker ratings. Around a quarter of all homes are terraced in the UK meaning lack of potential off-street parking locations. Retrofitting older houses with 7kW chargers and heat pumps will require at a very minimum, supply fuse upgrades from the DNO as well as potential wiring upgrades. Newer builds should be easier to retrofit. 40% of all motor vehicles in the UK do not have off street parking.
• Consumer Notification – People have a duty to notify the host DNO, but the lack of notification causes a problem especially on the older networks because the DNO can’t detect the clustering of LCT.
• System Operation – System stability, frequency issues, frequency excursion, fault ride through issues can all present themselves as has been identified by Sygensys in their Project REV report. These issues all need technological and smart solutions in place before EVs become more widespread.
• Government Policy – Could trigger a large wave of increased connections depending on subsidies or further policy changes i.e. ICE ban. Defining time of use tariffs and off-peak as the same time in the day e.g. 1am to 5am may result in peak demands shifting from traditional times to early hours essentially moving the problem, not solving it.
• Capacity – Do the DNOs have the capacity to host that capacity, at the low voltage LV level? All DNOs have submitted plans to reinforce the network as part of the regulatory period RIIO ED2.
• Thermal Constraints – Both at the transmission and distribution level.
• Cold Start – After a power outage, an increased need in sudden EV charging from consumers could cause an unmanageable loss of diversity, particularly at the LV level.
• Smart vs Dumb Chargers – ‘dumb’ chargers that exist in the current generation of EV chargers could cause an issue if adoption is more widespread. Smart chargers could assist network operators manage a constraint network and are a lot more predictable. The network infrastructure needs to stay one step ahead. However smart chagrin may present its own risks in the form of cyber security threats, maloperation risks and if large numbers of BEVs are used for System Operation tasks, the System Operator may not be able to view how much of that service is available resulting in them over-procuring competing services, leading to inefficient system operation.
• One-off Risks – Transitory constraints and peak events will no longer be predictable like the current demand curves that exist on the system today. Increases in wind, solar and battery installations will mean forecasting demands alongside potential faults on the system could result in large constraints on the network where there are concentrated EV demands.
• Looped Services – New builds cannot be looped. Stopped looping services in the 90s. Early 2020 all new builds and all service alterations are three phase supplies. Already a policy decision that every consumer can have a 12 kilowatt heat pump and a 7.4 kilowatt charger.Identifying existing looped services in housing is a significant task and will require significant civil engineering works to access the cables. Properties with looped connections would not be allowed to have BEV chargers and Air Source Heat Pumps due to the limiting nature of looped services.

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