No one knows for sure how motorists will use electric vehicles in the future, but the implications for the UK’s electricity infrastructure could be enormous. Lauren Moody, National Grid’s Power Demand Manager, explains why her team is busy assessing the possible impact of this growing mode of transport.
In National Grid’s Energy Strategy and Policy team, our job is to work out how much energy the UK will need in future. We look at all types of energy usage, from how will it be used and who will use it, to what kind of technology will be involved and broader factors like population growth.
On that basis, National Grid has created two different ‘Future Energy Scenarios’ (FES) – Slow Progression and Gone Green – to help us meet the energy demands of this century. The first envisages comparatively slow developments in renewable and low carbon energy in the coming decades, while the latter sees the UK meet its key environmental targets.
The potential role of electric vehicles (EVs) has been a major part of this research. Working with our partners at the Transport Research Laboratory, we’ve spent a lot of time looking at different types of EV, assessing their potential take-up and how much electricity they will need. Moreover, we’ve looked at current and projected sales, the types of consumer who may use EVs in the future and how they might fit within the broader landscape of renewable energy.
This is what’s called a ‘bottom-up’ model of projection and it’s an area we are busy developing. Previously, we worked to an econometrics model, which uses the past to judge what might happen in the future. Unfortunately, history isn’t always the best guide when it comes to energy demand, especially where energy policies may be involved, so the new bottom-up model takes a different approach, breaking things down as they are now and building the story from there. It’s given us a very detailed analysis of what may lie ahead for EVs, and, crucially, how much more investment in energy capacity and infrastructure we’ll need.
When electric vehicles plug in and charge, they add demand to both our facilities and our networks. At the moment, there are around 5,000 electric vehicles on the road in the UK. In Gone Green, there will be 3.2 million cars in the UK by 2030 and in Slow Progression there will be 0.9 million. On a cold winter day, the average electricity customer currently consumes 13 kWh. FES analysis assumes an average EV charge consumption of approximately 6.3kWh per day, which means an increase of almost 50% for that home.
So what can the energy industry do to prepare? As the transmission system owner and operator, we need to understand what the demand is at peak times so we can make sure we have the network capacity to respond. Of course it is unlikely that every EV owner will be charging their cars at the same time. We expect to see different charging patterns between commuters, second car owners and commercial vehicles based on their journey, destination and average mileage. The type of vehicle they choose, how long they need to charge it for and whether they will be fully charging or merely topping up are all determining factors as well.
Peak or off-peak?
Nevertheless, there remains a risk that a significant number of people will return home and charge their cars at our existing peak demand times, so the projected increase in electricity demand still requires a careful, strategic response. One of the biggest ways the industry can achieve this is through price incentives. One option being looked at is Time-Of-Use Tariffs (TOUTs), which make it more expensive to charge at peak times.
It’s a clear price difference, so our current FES projections are based on the assumption that EV owners will choose the cheap option and charge off-peak wherever possible. But these are only assumptions, and with these come the risk that we may be wrong. Fundamentally, it remains a huge unknown as to whether pricing and incentives will be strong enough to influence consumer behaviour in such a way that puts less stress on the energy system.
The stakes are huge. If such price incentives can’t influence how people charge their EVs, then by 2035 we could be looking at a peak demand increase by 30% from 67GW to 86GW. We’re continuing our research and analysis into EVs and how consumers will use them. The implications on the energy network are massive, so the findings will be of interest to everybody in the industry as we plan for the challenges of future energy in the 21st century.
Find out more
National Grid’s 2013 UK Future Energy Scenarios (FES) paint a picture of how the UK’s energy landscape might look in 2035 and as far out as 2050. For more on FES, click here.
Richard Smith, National Grid’s Head of Energy Strategy and Policy, explains how these scenarios have been developed.