Powering an electric future
Julian Skidmore, senior software engineer at embedded systems consultancy ByteSnap Design, explains why the creation of a UK-wide public charging infrastructure is essential for the success of electric vehicles.
The electric vehicle (EV) market is progressing rapidly with mainstream manufacturers including Nissan, Renault and BMW launching their own EVs. Despite EVs now selling in their millions, one barrier that is hampering EV adoption is the slower development of EV charging infrastructure here in the UK.
Battery EV sales in the UK are projected to be around 100,000 during 2020 and the government has set a goal for half of all new vehicle sales by 2030 to fall into the ultra-low emissions category. Yet, at current growth rates over 2010 to 2019, all registered vehicles will be battery EVs by the mid-2020s.
But, while 70% of car buyers are now considering purchasing an EV as their next car, according to a survey by Shell Energy Retail, and the younger generation is keen to have EVs, the availability of public charging points is an issue. Some 85% of survey respondents reported that there were simply not enough of them.
The charging of electric vehicles seems to be a barrier to their adoption. EV performance is rising thanks to battery capabilities growing rapidly, from a range of 100 miles to between 200 and 300 miles, and EV prices are falling. So how can EV charging infrastructure keep up?
Smarter EV charging
AC chargers with slower charging and lighter loading, like those used at home, are best for local or urban driving where most journeys are short, so their energy requirements won’t change over time. However, home charging is not a barrier to EV adoption. The problem is the availability of public charging points, which is not keeping up with the number of EVs sold
Rapid DC chargers are essential for longer journeys. Their roll-out is starting to catch up thanks to the charging rate’s impact on average speeds over battery size. If we want to put EVs on the motorway, rapid charging matters more than a large battery, but for local or urban driving there will be a market for smaller batteries for slow charging EVs. New cars in 2020 are likely to have modest batteries, short ranges and 7KW charging as standard.
Building a user-friendly charging network
Considering they power our driving future, current EV chargers are not very user-friendly. Payment methods can be inconsistent, billing mechanisms are frustrating, connections can be faulty or intermittent, systems can crash and some user interfaces are on the opposite side from the plug.
We are at the beginning of the EV revolution, and this presents an opportunity without the constraints of fossil fuel powered cars which need piping, tankers, stations, and just-in-time logistics. Better government support and initiatives to support charging locations and a good geographic availability of chargers, combined with subsidies for charging network providers, are all needed to help as the EV economy stabilises.
Another issue hampering the availability of public charging is incompatible systems and communications protocols."
Load balancing is also an issue, as distributed energy could cause intermittent supply. Usage restrictions and non-standardised interfaces represent a wasted engineering effort that may slow adoption down.
Another issue hampering the availability of public charging is incompatible systems and communications protocols. Charger manufacturers would like a comprehensive networking protocol between the charger and the car, but current specifications have led to a plethora of (crude) communications protocols along with incompatible plugs.
Manufacturers’ reluctance to provide useful EV battery charging states (to protect their patents) will also continue to inhibit the potential for smart EV charging.
Electric vehicles can be part of the energy solution, because batteries also represent a source of base-load microgeneration.
ByteSnap, in collaboration with a consortium of partners, is part of a two year project called Vehicle-to-Grid Intelligent Control (VIGIL), which aims to develop a new communication and control platform for vehicle-to-grid (V2G) and vehicle-to-building (V2B) systems.
V2G technology could mean that electric vehicles can return energy to the power grid when stationary and plugged in, increasing energy grid resilience and providing payback for EV drivers. V2G connectivity could also take advantage of the new phenomenon of renewable energy surplus. Germany is one country where too much green energy is available and consumers can experience negative energy prices.
VIGIL would promote comprehensive charging communications, in turn aiding EV adoption, with ByteSnap’s smart communications controller managing the charge going back into the smart building or substation. In turn, substation energy can flow into the smart building to charge EVs or return power to the grid.
The future of EV charging
App-less charging, where EV owners can tap a credit or debit card on a charging post to start and stop charging is something every EV driver would like, and which is now becoming available. Polar Ultrachargers already offers some charging points with a contactless payment method and Ecotricity Electric Highway plans a similar upgrade, even though it will result in higher charging costs.
Combining substations with urban car parks could help solve issues of inaccessible or easily damaged kerb-based charging sockets. Or, we could knock down a house in a street and replace it with a secure multi-storey car park with built-in charging facilities. Benefits of this would be the infrastructure staying in one place so it's much cheaper to implement, upgrade and maintain, the streets being clear of EVs, security and V2G facilities, load balancing etc.
Fully automated charging is the ultimate ideal, perhaps in the form of robots plugging in charging cables, but more likely via new inductive charging mechanisms in the future.
EVs are the most likely technology to replace fossil-fuelled vehicles. Driving the development of the charging technology, infrastructure, and supporting systems needed to make EV driving as effortless and attractive as a petrol or diesel vehicle is as critical to their deployment as the vehicles themselves.