Mainstream manufacturers like Nissan, Renault and BMW have all joined Tesla in launching their own electric vehicles. Driven by concerns over global heating and improvements in battery technology, electric vehicles are the most promising solution for emissions-free transit, but one barrier to EV adoption is the slower-developing EV charging infrastructure which can be inconsistent and difficult to use.
EV ownership is growing rapidly
An Opinium and Pure Planet survey revealed that 43% of UK residents would consider driving an EV while AA research in 2018 found that half of young people in the UK would like to own an electric vehicle.
Battery electric vehicle sales in the UK are projected to reach 100,000 in 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 BEVs by the mid-2020s. The availability of public charging points is an issue though as the AA survey found that 85% of respondents didn’t think there were enough.
Will charging availability and technology hold back EV adoption?
The charging of electric vehicles is a barrier to their adoption. While battery capabilities have grown rapidly, from a range of 100 miles to between 200 and 300 miles, EV prices are falling, consumer choice is growing and EV performance is rising. So how can EV charging infrastructure keep up?
AC/DC Charging
I recently showcased “Smart Charging” solutions for EVs at the Engineering Design Show (EDS). ByteSnap designed charge posts for the London Olympics in 2012 and is working on a number of intelligent EV charging projects, so we have strong expertise in this field.
AC chargers, like those at home, with slower charging and lighter loading are best for grid management with local or urban driving. That’s because most journeys are short, so their energy requirements won’t change over time. Home chargers obviously keep up with EVs sold, but public ones aren’t so they should be targeted, because they’re cheap and cover most cases.
However, rapid DC charger rollout is catching up and these are essential for longer journeys, because the charging rate has a much bigger impact on average speeds than battery size. If we want to put EVs on the highway, rapid charging matters more than a large battery, but for local or urban driving there will be a market for smaller batteries, slow charging EVs. Some of the new cars in 2020 will have modest batteries, short ranges and 7KW charging as standard.
EV chargers are less user-friendly than we’d expect from something that is powering our driving future. Payment methods can be inconsistent and billing mechanisms “nasty”; connections can be faulty or intermittent; systems can crash and some user interfaces are on the opposite side of the charger from the plug.
We wouldn’t accept this lack of service at a petrol station and that “EV journeys shouldn’t have to be that stressful.”
Infrastructure
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.
However, better government support and initiatives may be needed to support charging locations and a good geographic availability of chargers. Subsidies for charging network providers may also be needed while the EV economy stabilises.
There is also an issue of load balancing as distributed energy could cause intermittent supply. Usage restrictions and non-standardised interfaces represent wasted engineering effort that actually slows down adoption.
Lastly, charging points are unmanned, resulting in maintenance issues but perhaps presenting an opportunity for a new service industry.
Charger manufacturers would like a comprehensive networking protocol between the charger and the car, but the IEC 61851 and 62196 specifications have led to a plethora of (crude) PWM, CAN bus and IP over Power communications 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.
Vehicle to Grid technology
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 VIGIL (Vehicle-to-Grid Intelligent Control), which will see the development of 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 (called RAY) managing the charge going back into the smart building, or substation. In turn, substation energy can flow into the smart building; charge EVs or return power to the grid.
The future of EV charging
Appless 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 is becoming available. Some Polar Ultrachargers have a contactless payment method and Ecotricity Electric Highway plan a similar upgrade, even though it will result in higher charging costs.
Combining substations with urban car parks could help solve issues of kerb-based charging sockets which can be inaccessible or easily damaged.
We could knock down a house in a street (there’s always someone who wants to sell theirs) and replace it with a secure multi-storey car park with built-in charging facilities. The infrastructure stays in one place so it’s much cheaper to implement, upgrade and maintain; streets are cleared of EVs; the car park provides security; 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, inductive charging though this requires charging mechanisms to change yet again and therefore may be some time in the future.
At the end of my presentation “The EV Charge Point Journey: What’s the Final Destination,” I summarized that EVs are the most likely technology to replace fossil fuelled vehicles and that the nascent world of EVs is a rapidly accelerating, disruptive market; and charging technology and infrastructure is as critical to their deployment as the vehicles themselves.
The challenge for UK government and industry, and for other countries around the globe, is to not only drive the development of EVs but also the charging infrastructure and supporting systems to make EV driving as effortless and attractive as a petrol or diesel vehicle.
Author details:
Julian Skidmore, Senior Software Engineer at embedded systems consultancy ByteSnap Design
