Overcoming bumps in the EV road

When Prime Minister Boris Johnson revealed his Ten Point Plan for a Green Industrial Revolution back in November 2020, he brought the end date for the sale of new fossil-fuelled vehicles forward by a decade. This has placed extra pressure on automotive manufacturers and the Government to realise the nation’s EV capabilities in a much shorter timeframe than initially planned.

By 2030, it’s estimated that over a third of the cars and vans on the UK’s roads will be electric. The electrification of the automotive sector is a huge step towards decarbonising the UK and reaching net-zero carbon emissions by 2050, but it is undoubtedly a challenge. To achieve this goal, we must overcome several obstacles.

Facing a rough ride

When looking to purchase an EV, a main concern among consumers is its battery capability. Range anxiety is the fear that you may run out of charge mid-journey with no access to charging points. EV range varies depending on the model, but the distance EVs can travel on a single charge is typically less than their petrol or diesel alternatives.

In addition, an entirely new fuel source requires an entirely new infrastructure to facilitate simple charging. The Government has pledged to invest £1.3bn in charging infrastructure, but the number of charging points across the country will need to increase over ten-fold by 2030 to meet demand - from the current 35,000 to over 400,000.

Furthermore, the increased demand for EVs will create more load on the National Grid, which was not designed to facilitate the electrification of the entire country’s fleet. As a result, EV charging could negatively impact the UK’s power system, resulting in an imbalance between supply and demand. Transmission networks are likely to need further investment and additional electricity generation resources to power an entire added sector of the country.

Overcoming hurdles through design

All of these concerns focus on infrastructural problems, which require costly, large-scale solutions. However, by designing EVs with these challenges in mind, automotive manufacturers can help to mitigate their impact on consumers and contribute to a simpler EV rollout.

Concerns around battery capabilities, access to charging points and sufficient electricity availability can be alleviated, in part, by making energy efficient EVs that can travel the furthest possible distance on the smallest possible amount of power. One technology crucial to achieving this is regenerative braking.

In regenerative braking, as a vehicle slows down, its kinetic energy is converted into a form that can be stored and reused, rather than just dissipating it as wasted heat. On average, regenerative braking is between 60 and 70% efficient, which means that around two thirds of the kinetic energy lost during braking can be retained and stored in the EV battery and used later for acceleration, drastically improving the energy efficiency of the vehicle.

Reliable resistors

The principle of regenerative braking is simple, but in practice further technologies are required to ensure the vehicle operates safely. If the battery is already fully charged, or kinetic energy is being converted at a rate too fast for the battery to handle, then regenerative braking isn’t viable. However, this excess energy has to go somewhere to make sure the EV stops when the driver brakes.

To manage excess energy, a Dynamic Braking Resistor (DBR) is used to safely dissipate the energy and ensure the vehicle’s braking system remains operational. Cressall’s EV2 DBR is uniquely designed to separate the resistor elements from the coolant and is available in up to five-module assemblies to meet high-power requirements.

The EV2 also contributes to an EV’s energy efficiency since it is water-cooled, which means that heat can be dissipated safely without the need for extra components, such as fans, as is the case with air-cooled resistors and has a total weight 15% less than a conventional DBR. These weight-saving properties lighten the load of the vehicle itself, meaning it can travel further on the same amount of fuel.

EVs are the future of the UK’s automotive market, but their deployment will not come without challenges. However, by anticipating these challenges and integrating technologies that can help to overcome them, car manufacturers can support the Government in a successful, national, EV rollout.