A fresh approach
National Grid has recently conducted a Network Innovation Allowance (NIA) project working with partner Element Energy to assess the potential of electric vehicles and heat pumps to provide frequency response. Rhiannon Grey, Balancing Analyst, explains the findings and why these two technologies could play an increasingly important role in fine-tuning Great Britain’s future electricity system.
A fresh approach
“There are no fundamental technical barriers to providing frequency response, but there is still a lot of work to be done.”
Rhiannon Grey, Balancing Analyst.
By 2030, electric vehicles and heat pumps could contribute 1200MW of Frequency Response, equivalent to 82% of GB’s requirements.
Source: National Grid.
Managing the frequency of Britain’s electricity system within statutory limits is already a challenge – it’s a bit like a never-ending, second-by-second balancing act to harmonise demand and total generation.
National Grid has a role to keep system frequency within set limits. This frequency is determined by the real-time balance of electricity supply and demand across the country and is important because it enables us to operate a stable, reliable transmission network to power our homes and businesses.
Maintaining system frequency will continue to pose challenges in future because the country’s generation mix is changing. More renewable generation such as wind and solar power, which is less predictable and flexible, is replacing traditional sources of electricity.
These changes mean that we need to find new and innovative ways to manage frequency; this is where electric vehicles and heat pumps could have a role to play.
With disruptive new technologies such as electric vehicles and heat pumps, we have no historical information to understand how they will affect electricity consumption and therefore system balancing. On the flip side, they also represent an opportunity to develop new and innovative services.
The project we have done shows that there is significant potential for both technologies to provide frequency response. At the moment, deployment of both is on a very small scale – there are only about 20,000 plug-in electric vehicles on Britain’s roads today – but by 2030 large scale adoption could change that dynamic.
Our research found that together, electric vehicles and heat pumps could provide an annual average of 80% of National Grid’s projected frequency response requirement by 2030 and could deliver about £100 million of annual revenue to be shared between suppliers, aggregators and consumers. This revenue would be in the form of payments by National Grid to provide frequency response, in much the same way as happens today.
Of course, when we are talking about the period of 2030 and beyond, there are some unknown factors, in particular around the uptake of technologies, but we can make some projections. As an example in the medium uptake scenario for electric vehicles set out in our Gone Green scenario in the 2015 Future Energy Scenarios, they could contribute 754MW of frequency response, the equivalent of a large combined cycle gas turbine plant, which is around 52% of the projected 2030 requirement.
Likewise, industrial and commercial heat pumps could contribute 447MW of frequency response in the medium uptake scenario, equating to 30% of the total we believe will be needed by 2030. This is similar to the proposed size of an offshore wind farm due to connect in the next few years.
How it would work
Electric vehicles are typically plugged in for eight hours a day but they only need three hours to charge so there is potential for frequency response via interrupted charging. From a consumer perspective there would be no negative impact – charging might be interrupted for a few seconds if frequency fell, or the charge could be reduced for a short time if required.
Similarly, with heat pumps, which use electricity to heat the home rather than gas, they would simply switch off for a few minutes in response to frequency requirements. The timescales are short so there would be no impact on the household.
Barriers to success
There are no fundamental technical barriers to providing frequency response but there is still a lot of work to be done, particularly in the areas of metering and communications, to equip electric vehicles and heat pumps with the capability required.
At present, heat pump controls and home energy management systems often do not have the required metering and telemetry capability. A clear driver is needed to encourage manufacturers to develop these solutions. We also need to have a joined up approach across the country so that the technologies are able to ‘talk to each other’ in a real-time situation.
The first option is to focus on incentivising consumers, either by enabling them to make money from their electric vehicle or heat pump, or to save money. The big question is whether the incentive will be strong enough to encourage people to sign up. Although £100 million in revenue is a significant amount of money, the large number of assets involved, potentially millions nationwide, means that the benefits to the individual consumer will quite modest – we estimate a £50 annual benefit per heat pump and £25 per electric vehicle for residential consumers.
Option two is to look at incentivising manufacturers. At present there is no financial benefit to manufacturers to develop vehicles and heat pumps with the built-in capability to be able to adjust their energy consumption in a way that is linked to frequency response. Providing incentives to manufacturers could be another way of boosting the market in support of frequency response.
But what if neither of these options achieve success? The research also looked at a third option which was to introduce a mandated approach whereby consumers would be signed up to be involved automatically. However we concluded that the more compelling option was a commercial model that encouraged fresh thinking and innovation in the market.
The next steps
With the expansion in deployment of electric vehicles and heat pumps likely to increase significantly after 2020, it would be beneficial to develop demonstration projects that get to grips with the technical issues. We also need to include frequency response provision in strategic planning so that these opportunities can flourish.
Following the event, we will review feedback and consider possible next steps.