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Blog Post 8 December 2020

Smart charging towards a zero emission future

Electric vehicles (EVs) are an increasingly attractive option for consumers thanks to their environmental benefits, lower running costs and ever-improving range of models. The concept of ‘smart charging’ will be integral to the widespread adoption of EVs by ensuring that electric car owners have easy access to affordable low carbon electricity to charge their vehicles.

The key to encouraging greater electric vehicle adoption is to automate and simplify the process of ‘smart charging’, in accordance with the needs of EV drivers.

Current electric vehicle use

There has been a healthy increase in registrations of electric and plug-in hybrid vehicles in recent years. The graph below shows the recent shift in Scotland.

New plug-in vehicle registrations in Scotland as a percentage of total new registrations. BEV – battery electric vehicle; PHEV – plug-in hybrid electric vehicle.

The increasing uptake of EVs has been supported by the development and expansion of Scotland’s charging infrastructure and network. Scotland’s public electric vehicle charging network, ChargePlace Scotland, surpassed 1,000 publicly available electric charge points in August 2019. The average distance between any given location to the nearest charge point Is 2.78 miles in Scotland, compared to 3.77 miles In England.

This trend is likely to continue as environmental concerns heighten, charging infrastructure improves and vehicle technology continues to develop, resulting in more affordable EV models.

Recent car registration trends (September 2020) reflect this:

20202019% change
MHEV diesel13,4848,10166.4%
MHEV petrol30,3825,819422.1%
Car registrations by type between 2019-20. Source: SMMT (2020)

In Scotland, there is strong governmental support for the adoption of EVs, as evidenced by the nation’s Programme for Government over the past three years, which includes aims to:

  • phase out the need for new petrol and diesel cars and vans by 2032
  • decarbonise Scotland’s public sector cars by 2025
  • make Scotland a ‘net-zero’ society by 2045

The combination of strong targets and incentives towards electric vehicle adoption from the Scottish Government, alongside widespread investment and innovation within the private sector, is likely to drive down ownership costs and accelerate the adoption of EVs in the coming years.

The National Grid recently released its 2020 Future Energy Scenarios, providing forecasts on EV uptake across a range of scenarios. Most examples predicted EV ownership in the UK to increase to over 30 million by 2040, which will ultimately increase demand on the UK electricity grid. Smart charging will be essential to accommodating this increased demand for electricity.

The concept of smart charging

One of the key benefits of switching to electric vehicles is the lower running costs when compared to a petrol or diesel car. Although charging an EV to a range of 100 miles will cost approximately £4 to £6 in additional electricity at home, or £8 to £10 if using public charge points, driving 100 miles in a petrol or diesel car costs between £13 and £16.

Smart charging will result in additional cost savings for electric vehicle drivers because the concept involves using cheap, low carbon energy. This is achieved by shifting energy demand from peak times, which will also minimise network congestion. Smart charging has the potential to save the average electric car driver an estimated £230 per year, compared to charging on a standard energy tariff (, 2020).

The current energy system has been designed to meet peak demand between 5-8.30pm in the evening. Currently, the use of fossil fuel power plants is required to meet this demand, leading to higher electricity costs during these periods. At other times there can often be underused generation from renewable sources and network capacity. Energy generation during these off-peak hours is usually cheaper and cleaner.

Balancing the grid

With a time-of-use tariff, drivers are incentivised to charge ‘off-peak’ overnight, when electricity is cheapest. Using an app, the driver can set their vehicle to charge for a time when low carbon energy is readily available or when the price is lowest. Most modern smart charger apps will calculate the best time to start and stop charging to minimise costs. Users can also set a minimum charge level (for example, enough charge for their commute the following day) they do not want their battery to fall below. Most drivers won’t notice the difference if their vehicle is fully charged by 4am, rather than 2am, but will still see the difference in their energy bills, and drivers still have the choice to start charging immediately if they choose.

To ensure as many people as possible adopt electric vehicles, smart charging must be affordable, easy to understand and convenient. Although the current impact of electric vehicles on the energy network is low, increased uptake could lead to localised pressure on the energy network. There is already a wide range of EV tariffs, and comparison websites can be a helpful tool in helping consumers decide the best tariff for their needs. The UK Government has ensured that consumers can change electricity tariff easily without being penalised, helping consumers get the best possible deal.

Encouraging drivers to charge their electric vehicles overnight, or at other off-peak times, will help balance the grid, reducing the need to use non-renewable power to cover peak demand. In the long run, smart charging will make it cheaper for consumers to charge their vehicles and will make it easier to integrate a larger number of electric vehicles into the national grid in a sustainable and affordable way.

The graph above shows how smart charging can level out demand on the electricity network by reducing EV demand during peak hours. Source: UK Government (2019).

Vehicle-to-grid charging

Vehicle-to-grid (V2G) charging technologies are the next step. Rather than just controlling the time and rate of charge in response to demand like smart charging, V2G allows energy stored in the vehicle’s battery to be exported to the grid during periods of high demand. Drivers are rewarded for their flexibility, which benefits the grid. Octopus Energy’s Powerloop project, in which Energy Saving Trust is a partner, is a good example of how V2G works.

Smart charging will be essential in enabling the widespread adoption of electric vehicles. It will ensure that EV charging activities do not put a strain on current energy networks, while providing a cheap and convenient way for consumers to charge and monitor their vehicles.