Are you interested in electric cars but struggling to understand the terminology? Don't worry! Our simple guide helps you through the basics.
For every new technology there are new terms, and hybrid and electric vehicles (EVs) are no different. People talk about regenerative braking, battery cycles and quick charging – plus they throw around acronyms like ICE, BEV and ZEV. If you're considering buying or leasing an electric car you probably have lots of questions around how they work, which is best, and whether they're the right choice for you. But how can you decide if you don't understand what people are talking about?
In this guide we've picked out the most common and important terms around electric, hybrid and fuel-efficient vehicles. We'll explain what they mean, why they're important, and how things might change over the next couple of years.
(electric vehicle) / BEV (battery electric vehicle)
An EV is simply a fully-electric vehicle, without any conventional (petrol or diesel) power.
(Adaptive Cruise Control or Autonomous Cruise Control)
Already fitted to many cars, adaptive cruise control uses sensors to work out how fast the car in front is travelling and keeps you a safe distance behind it. It's not just for EVs: it helps all cars travel at a constant speed, avoiding 'concertinas' on the motorway where everyone brakes, then speeds up again.
Some high-end cars are now taking ACC to a new level, adding more sensors and pulling in very detailed road information from SatNav. This helps them save energy by predicting the best speed ahead of time. For example, by detecting a slower speed limit ahead and coasting to slow down, instead of using the brakes.
(Autonomous cars / self-driving cars)
You've probably heard of Autopilot – the self-driving technology pioneered by Tesla. In fact, many cars can self-drive to some degree, from simple cruise control, to almost fully automatic driving in some limited circumstances, such as a motorway cruise.
(cycle life / charge cycles)
The rechargeable batteries used in electric and hybrid cars should last for many hundreds, or thousands, of charge cycles – i.e. charging up, being used, then charging up again. Car makers usually guarantee a minimum. Batteries won't fail at the end of their cycle life, but they won't store as much energy, so the car's electric range will be smaller.
(rapid, fast or slow?)
There are a variety of standards for charging points, but they range from slow, through fast, to rapid. Rapid are the quickest, generally capable of charging cars to 80% in 20-40 minutes, depending on how big the battery is and how much charge it's holding to start with. Why 80%? Beyond that charging has to slow right down to avoid damaging the batteries.
Fast chargers take a few hours to recharge an EV. There are a few types, but a professional installer can fit the slowest, 7kW type in most homes or workplaces – find out more about charge stations here.
If all else fails you can generally get a slow charge anywhere – using a standard three-pin UK plug if necessary. It's a bit of a last resort, though: with a maximum 3kW available, it could take more than a day to recharge the biggest EV batteries.
(hybrid electric vehicle)
A hybrid vehicle combines a conventional engine – usually petrol – with batteries and an electric motor. But why? Hybrids usually use smaller and more efficient engines, relying on the electric motor for a bit of extra kick when needed. Cleverly, the motor is also used to recover energy and recharge the battery during braking or coasting (see regenerative braking, below). The end result is usually the same performance – or better – from less fuel.
There are two main types of hybrid. In a mild hybrid, the motor only helps the engine and recovers energy. In a full hybrid, the vehicle can run on its conventional engine, or the electric motor, or both working together.
(Internal combustion engine)
We've all grown up with the internal combustion engine – usually just calling them a petrol or diesel engine. Technically an ICE is any engine that burns fuel to generate power, so you could include jets or even rockets – not that you'd expect to find one in a car!
ICEs are on the way out, but they're not dead yet. Until EVs hit the mainstream, car makers are still improving conventional engines.
This is simply a measure of how much energy a battery stores, with a higher figure giving a greater range. A hybrid car's batteries might store around 1kWh – enough for a couple of miles – while the range-topping Tesla Model S can store 100kWh, giving it a range of up to 335 miles.
Plug-in hybrid / plug-in hybrid electric vehicle (PHEV). A PHEV is essentially a hybrid vehicle with a bigger battery, giving it a longer all-electric range – perfect for city driving. As with a normal hybrid, the batteries are recharged by the electric motor during braking or coasting, and sometimes with help from the engine, but a full charge usually means plugging in.
Today, a PHEV offers a better range than the typical electric car, but to get the most from one you really either need to live near a charging point, or have your own.
Quite simply, range anxiety is worry about the battery running out of power before reaching a destination.
Moving objects store up kinetic energy, and to stop them you have to remove it again. When you hit the brakes in a normal car they create friction, converting the car's kinetic energy into heat. That's great for the cat that just ran in front of you, but terrible for fuel economy: getting going again means burning more fuel.
One of the best things about an electric motor is that you can also use it as a generator. Hard braking in an EV or hybrid still relies on friction, but during coasting or gentle braking the motor harvests the car's kinetic energy, slowing it down and recharging the batteries. It's not 100% efficient, but most of the energy is saved and available to get you going again.
Energy doesn't appear by magic – fossil fuels have to be pumped out of the ground, refined and transported to the fuel pump, while EVs and PHEVs have to get their electricity from somewhere. Well-to-wheel describes the total environmental impact of different fuels from their point of origin, to the point at which they're used.
Emissions are anything created when a fuel is used. They can be as innocuous as water, but generally include at least the greenhouse gas carbon dioxide (CO2), along with gases like nitrous oxide (NO) and particulates.