Guide to electric vehicles
Questions & Answers
Sales of electric cars are currently growing around the world. Until a few years ago, electric cars were considered a niche product, but now almost every car manufacturer is launching new electric vehicle models with an ever-increasing range in kilometres.
Today, the number of electric cars globally has reached more than 3 million, according to figures from the "Global Electric Vehicle Outlook 2018" study by the International Energy Agency. Although this represents an extremely small percentage of the total number of vehicles circulating around the world, the total number of electric vehicles has grown about 20 times in the last 6 years. (Source: Bloomberg New Energy Finance)
The areas globally with the largest number of electric cars are China, Europe and North America. According to Bloomberg New Energy Finance, the market will continue to grow at a fast pace.
We often here about different models of electric or hybrid cars, so we will explain the difference:
- Fully electric vehicles (called BEVs or Battery Electric Vehicles) have an electrochemical storage system (a battery) as its only energy storage system on board. One or more electric motors generate mechanical energy (and the energy is recovered when braking). They are changed through the electrical grid.
- Chargeable hybrid vehicles (called PHEVs or Plug-in Hybrid Electric Vehicles) have a battery storage system that can also be charged through the electrical grid and a conventional petrol engine (with fuel tank). The combustion engine and electric motor provide mechanical energy (the energy is recovered when braking).
- Conventional hybrid vehicles (called Full Hybrid) have a battery storage system that cannot be charged from the electrical grid, as well as a conventional petrol engine (with fuel tank). The combustion engine and electric motor provide mechanical energy (the energy is recovered when braking).
For many people, electric mobility is still a distant world, almost futuristic, about which all sorts of things have been said and written. The truth is that the electric car is poised to become the vehicle of the future. Today, there are more than 3 million electric vehicles on the roads and approximately 1 million of those were acquired in 2017 alone. Most of the electric vehicles in circulation are concentrated in China, United States, Japan, Norway, United Kingdom and France (Source: Bloomberg New Energy Finance).
Electric cars offer several benefits:
- They are good for the environment
- They are more efficient than traditional vehicles
- They have adequate range for average daily journeys
- They bring benefits to the electrical system
- The range of models is constantly growing
- They are becoming more accessible as prices go down
- They are fun and exciting.
There are four main elements to be considered:
- Battery capacity: corresponds to the equivalent capacity in a combustion engine car and, in the case of an EV, is indicated in kWh.
- Range: depends on the battery capacity and, for models on sale in European countries for example, varies from 100km for the Renault Twizy to 632km for a Tesla Model S. The range also varies according to other factors, such as personal driving style, road conditions, external temperature, heating and/or air conditioning and pre-heating.
- Integrated battery charger maximum load: the power of a battery charger is determined by the voltage, which can be 230V (single-phase) or 400V (three-phase), and by the charge current (for example, 10A, 16A, 24A, 32A, etc) and varies from 2.3 kW (slow Alternating Current charge through a cable with domestic plug) to 50 kW (fast Direct Current charge). This determines the speed in which the battery can be charged.
- Vehicle charging cable: all vehicles are compatible with one of two types of charging cables, supplied when the car is purchased or rented. These can be used at public and domestic charging stations.
The maintenance of an electric car costs less than that of a conventional combustion engine vehicle. Electric motors have fewer movable parts subject t wear (such as the clutch) and no consumable fluid, different from conventional cars. Consequently, they are cheaper and easier to maintain. The wear of brake pads is also reduced thanks to the use of energy recovery systems during braking. Finally, the lifespan of the battery is comparable to that if the car itself and, as such, it does not require maintenance.
The maintenance of electric vehicles can be performed by mechanics authorised by the car manufacturer.
When it comes to domestic and school runs, going out with friends or even delivering goods, the distances covered in most countries vary on average between 40km and 60km a day (source of data: Goldman Sachs "Journal of Modern Power Systems and Clean Energy, 2015”). In any case, 95% of car journeys do not exceed 200km, according to a study by the US’ National Household Travel Survey (NHTS). Whatever the route, with an electric car there is no difference: these distances can be easily covered by the electric cars currently on the market.
The average range of electric cars is enough to cover 95% of day-to-day journeys.
Today electric cars already offer better environmental performance than any other alternative available in terms of CO2 and other pollutant emissions, as they are the only technology that offers total elimination of local emissions of nitrogen oxide (NOx) and particulate material (PM) during use.
Furthermore, considering the production of carbon-free electricity in the future, an electric transport system will be sustainable and free of CO2 emissions.
For example, taking into account the existing electricity production plants in Italy (where renewable sources contribute 33% of the total mix), it is estimated that the emissions of an electric vehicle “in a lifecycle” are around 70% compared with a petrol vehicle and around half of a methanol vehicle’s. However, as the electricity generation becomes almost carbon-free - a scenario projected to become a reality by 2050 - the “lifecycle” emissions for electric cars will be approximately zero.
Electric vehicles bring improvements to the air quality. This enables, especially in large cities, a reduction of the direct impact on people’s health, which translates into lower medical and healthcare costs.
Finally, we should not forget another type of pollution: noise from traffic and from the engine exhaust fumes that we need to live with every day. Electric cars are silent and its use enables significant improvements in people’s quality of life.
False! To cover the same distance, an electric vehicle requires three times less energy than a vehicle with a conventional combustion engine. In other words, electric cars travel three times more than a car fuelled by petrol with the same amount of energy used.
In a “lifecycle” analysis, petrol cars require the following steps:
- The refinement of crude oil into petrol
- Transformation of the petrol in mechanical energy by the engine
The global efficiency of this process is of around 18-19%.
The phases related to electric vehicles, however, include:
- Electricity production
- Transmission through the grid
- Transformation by the motor of the electrical energy stores in the batteries into mechanical energy.
In this case, the general efficiency grows to around 52%.
With higher efficiency and energy economy, electric mobility contributes to reaching the emission reduction targets established in the Paris Accord (COP21), the 21st annual conference between signatories of the United Nations Framework Convention on Climate Change, in which national commitments were taken on in terms of energy efficiency and emissions reduction.
Furthermore, if we consider a scenario with 1,000,000 electric vehicles, the increase in national electricity consumption to charge them would be of just 0.3%. This amount can be achieved considering the average consumption of 0.15 kWh/km for a fully electric car and 0.25 kWh/km for a plug-in vehicle, with an annual average distance of 10,000km a year for all electric cars and 5,000km a year for plug-in cars with 60% of charging at public charging stations. Given those assumptions, the additional consumption of 1 million electric vehicles would equal 1.3 TWh a year.
Electric cars also help the grid, because in addition to using electricity, they can also work as “batteries on wheels”.
Thanks to smart changing systems, when an electric car isn’t charging, it can return the electrical energy stores in its battery to supply the grid or charge it when the electricity prices are lower. These flexibility services - in countries where there already is a regulatory system that enables these technologies - create economic benefits not only for the grid operator, but also for final customers, whose electric cars can be charged when the prices are lower and can return energy to the grid when the prices are higher.