Guide to electric vehicles
Questions & Answers
Electric car sales are currently gathering pace around the world. Until just a few years ago, electric cars were considered a niche product, however, now almost all car manufacturers are releasing new electric vehicle models with an ever-greater range in km.
Today, the number of electric cars in the world reached over 3 million, according to data from the study "Global Electric Vehicle Outlook 2018" by the International Energy Agency. Although this represents an extremely low percentage of the total number of vehicles on the road worldwide, the total number of electric vehicles has increased approximately 20-fold in the last 6 years (Source: Bloomberg New Energy Finance)
The areas of the world with the greatest penetration of electric cars are China, Europe and North America. According to Bloomberg New Energy Finance, the market will continue to grow at a very rapid pace.
We often hear about different models of electric or hybrid cars, so let's explain:
- Fully electric vehicles (so-called BEVs or "Battery Electric Vehicles") have an electrochemical storage system (a battery) as the only on-board energy storage system. One or more electric motors generate mechanical power (and energy is recovered from braking). They are chargeable from the electricity grid.
- Chargeable hybrid vehicles (so-called PHEVs, or "Plug-in Electric Vehicles"), have both a battery storage system that can also be charged from the grid and a conventional petrol engine (with fuel tank). The combustion engine and electric motor provide mechanical power (energy is recovered from braking).
- Conventional hybrid vehicles (so-called "Full Hybrid"), which have both a battery storage system that cannot be charged from the grid as well as a conventional petrol engine (with fuel tank). The combustion engine and electric motor provide mechanical power (energy is recovered from braking).
For many people, electric mobility is still a distant, almost futuristic world about which all sorts of things have been said and written. The truth is that the electric car is set to become the car of the future. Today, there are more than 2 million electric vehicles on the road, about 1 million of these were purchased in 2017 alone. Most of electric vehicles in circulation are concentrated in China, the United States, Japan, Norway, the United Kingdom and France (Source: Bloomberg New Energy Finance).
Electric cars offer numerous advantages:
- They are good for the environment
- They are more efficient than conventional vehicles
- They have an adequate range for average daily journeys
- They bring benefits to the electricity system
- The range of models is growing constantly
- They are becoming more accessible as their price falls
- They are fun and exciting.
The advantages of driving an electric vehicle in Romania are both financial and practical. First of all, the Romanian Government is offering a generous subsidy, of 10.000 €, to those who want to buy a zero emission fully electric car and thus join the group of drivers that contribute to higher air quality. Electric cars are silent and they adapt perfectly to the urban environment, given that the battery charges when the driver uses the brakes, and city traffic offers maybe too many opportunities to slow down. As the infrastructure of charging stations will grow, electric car owners will have an increasingly higher freedom to move, which will allow them to travel across the country without a care.
There are four main elements to consider:
- Battery capacity: corresponds to the equivalent of the tank capacity of a combustion engine car and is indicated in kWh.
- Range: depends on battery capacity and, for the models on sale in Italy, it varies from 100 km for the Renault Twizy to 632 km for the Tesla model S. The range also varies depending on various factors, including: personal driving style, road conditions, outdoor temperature, heating/air conditioning and preheating.
- Maximum power of the onboard battery charger: the power of a battery charger is determined by the voltage, which can be 230V (single-phase) or 400V (three-phase), and by the charging current (e.g., 10 A, 16 A, 24 A, 32 A, etc.) and ranges from 2.3 kW (slow AC charging via a cable with a domestic plug) to 50kW (fast DC charging). This determines how quickly the battery can be charged.
- Vehicle charging cable: every vehicle is compatible with one or two types of charging cables, which are supplied when the car is purchased or leased. These can be used at public or home charging stations.
Maintenance of an electric car costs less than for a conventional combustion engine car. Electric motors have far fewer moving parts subject to wear and tear (such as the clutch) and no consumable fluids in difference to conventional vehicles. Consequently, they are cheaper and easier to maintain. Wear on the brake pads is also reduced, thanks to the use of energy recovery systems during braking. Finally, the service life of a battery is comparable to that of the car and is therefore not subject to maintenance.
Maintenance of electric vehicles can be carried out by mechanics authorized by the car manufacturer.
When it comes to home-work and home-school routes, going out with friends, or even goods deliveries, distances travelled in most countries range on average between 40 and 60 kilometers a day (Data source: Goldman Sachs "Journal of Modern Power Systems and Clean Energy, 2015”). In any case, 95% of car journeys do not exceed 200 km, 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 covered easily by the electric cars currently on the market.
The average range of electric cars is sufficient to cover 95% of day-to-day journeys.
Today electric cars already have a better environmental performance than all of the alternatives on the market in terms of both CO2 and polluting emissions, as they are the only technology that allows the total elimination of local nitrogen oxide (NOx) and fine particulate matter (PM) emissions while driving.
Moreover, with a view to carbon-free power generation in the future, an electrified transport system will be sustainable and free from CO2 emissions.
For example, considering the current power generation facilities in Italy (in which renewables contribute 33% of the total mix), it is estimated that the emissions of an electric vehicle "from well to wheel" are about 70% less than those of a vehicle running on petrol and about half of those of a methane vehicle. However, as electricity generation becomes almost totally carbon free – a scenario that is forecasted to become reality by 2050 – “well to wheel” emissions for electric cars will be approximately zero.
Electric vehicles bring improvements in air quality. This makes it possible, especially in large cities, to reduce the direct impact on people's health, resulting in lower medical and healthcare costs.
Finally, we must not forget another kind of pollution: the noise of traffic and engine exhausts that we have to live with every day. Electric cars are quiet, and their use enables significant improvements in people’s quality of life.
False! To travel the same distance, an electric vehicle requires 3 times less energy than a conventional combustion engine vehicle. Or in other words, electric cars travel three times farther than a petrol-fueled car with the same amount of energy used.
In an energy analysis "from well to wheel", petrol cars require the following steps:
- The refinement of crude oil into petrol
- Transformation of petrol into mechanical energy by the engine
The overall efficiency of this process is around 18-19%.
The phases related to electric vehicles, however, include:
- Electricity production
- Transmission over the grid
- Transformation by the motor of the electrical energy stored in the batteries into mechanical energy
In this case, the overall efficiency rises to about 52%.
With greater energy efficiency and savings, electric mobility contributes to achieving the emission reduction targets set out in the Paris Agreement (COP21), the twenty-first annual conference between signatories of the United Nations Framework Convention on Climate Change, at which national commitments were made in terms of energy efficiency and reducing emissions.
Moreover, if we consider a scenario of 1,000,000 electric vehicles, the increase in national electricity consumption to charge them would amount to just 0.3%. This figure can be obtained by considering average consumption of 0.15 kWh/km for a fully electric car and 0.25 kWh/km for a plug-in vehicle, with an average annual distance of 10,000 km a year for all electric cars and 5,000 km a year for plug-in cars with 60% charging at public charging stations. Given these assumptions, the additional consumption for 1 million electric vehicles would be equal to 1.3 TWh each year.
Electric cars help the grid, because in addition to using electricity, they can also serve also "batteries on wheels."
Thanks to smart charging systems, when an electric car is not charging, it can return the electrical energy stored in its battery to service the grid or charge when electricity prices are lower. These flexibility services – in countries where a regulatory system enabling these technologies is already in place – generate economic benefits not only for the grid operator, but also for end customers, whose electric cars can be charged when prices are lower and can feed energy back into the grid when prices are higher.