EV charging points set to rapidly increase in numbers
The number of electric vehicle (EV) charging points available in Europe is increasing year-on-year as EVs increase in popularity, though this is happening faster in some markets than others. According to the latest figures from the European Alternative Fuels Observatory, the UK now has more than 12,000 electric vehicle charging points. This was boosted further when the fuel company Royal Dutch Shell introduced EV charging points at some of its filling stations in the UK and the Netherlands in the second half of 2017. Germany, meanwhile, has around 25,000 charging points available.
By far the European leader in this area is Norway, where EVs represented nearly 40% of the nation’s passenger car market in 2016, selling 62,000 models in a country of 5.2 million people. The total number of EVs on Norwegian roads is close to 500,000, with around 9,000 active charging stations. One of these is the world’s largest fast charging station, opened earlier this year, where up to 28 vehicles can be charged simultaneously in under half an hour.
Numbers of EV charging points are set to increase dramatically under a draft EU directive expected to come into effect in 2019. This directive will mean every new home that is built after that date, or every home refurbished, will require an EV charging point, while 10% of parking spaces in new buildings will also need EV charging points by 2023. The idea is to make EV use a more convenient and realistic alternative to hybrids and diesel/petrol cars, but this scheme also has wider benefits. A large number of connected EVs' batteries may be used as an extended part of the electricity grid, using energy from the batteries to maintain supply when renewable sources fall short (especially at night, when most cars aren’t used and there is less available solar power).
The design challenges for domestic and commercial EV charging solutions are many and varied. They range from accurate and secure user authentication and interface with billing systems to public safety and planning issues, to increasing the capacity and functionality of the electricity grid for this new type of load.
Design challenges for the charging systems specifically include the variety of power levels and battery sizes that will be used. While the power levels available at charging points vary, they are broadly divided into three categories: level 1, level 2 and level 3. Level 1 is 3kW single phase AC charging at 13 or 16A, 240V, with a grounded plug, suitable for domestic charging in a home or garage. Level 2 is up to 20kW charging with three-phase AC, 240V, up to 80A; referred to as ‘slow charging’, it’s still a lot faster than level 1, and is suitable for commercial and some domestic installations. Level 3 is DC charging at very high currents and voltages (up to 400A/600V), delivering up to 240kW and referred to as ‘fast charging’. These fast-charging installations will be installed in locations such as service stations as they are the key factor in allowing convenient inter-city travel in EVs. The current situation in Europe is there are roughly 20 slow charging points to every fast charging point available, though this gap is reducing, especially in countries like Norway and the Netherlands where there are specific government initiatives aimed at increasing the number of fast charging points.
The speed of charging is also dependent on batteries. While there is a wide variety in use today, they are broadly split into two groups: small batteries such as those used in plug-in hybrids (PHEVs), which charge at 3.7kW max; and large batteries in EVs which can handle a lot more. For example, the Nissan Leaf’s battery can accept 7kW AC or 50kW DC, while the Tesla Model S can charge at 22kW AC or 120kW DC.
CCS includes four main connector types for vehicle charging (Image source: CharIN)
Standards for EV charging connectors have been developed to standardise the format for maximum interoperability. The leading standard is the Charging Interface Initiative (CharIN)’s standard, called the Combined Charging System or CCS, which specifies four connector types (see image above). Type 1 is for single-phase AC charging in the USA, type 2 is for single or three-phase charging in Europe, combo 1 is for AC and high-power DC charging in the USA (compatible with type 1) and combo 2 is for AC and high-power DC charging in Europe (compatible with type 2). CCS also specifies a powerline communication (PLC) implementation for charging control and safety measures which use pulse-width modulation (PWM).
ITT Cannon's ECIER outlet for charging points can be used at up to 63A
Aptiv's type 2 cable assemblies are ready for integration into charging stations
TE's AMP+ charger and cable assembly offers 16A charging from home sockets or 32AQ charging from charging points
Connection solutions for EV charging points are widely available. For example, ITT Cannon offers a number of solutions under its VEAM transport connector brand, including captive and jumper cable solutions for charging points and vehicle inlets. Aptiv’s range for EV charging includes chargers and charging cables, including its portable EV charger and charge coupler pigtails for integration into charging stations. TE Connectivity also has a portfolio of chargers, charging cables, inlets and outlets. For advice on specifying connectors or cable assemblies for your EV charging infrastructure project, get in touch with our team of technical specialists in your local language by clicking the Ask an Expert button to the right of this post.