The future belongs to electromobility: The technology ensures that vehicles are environmentally friendly, quiet and efficient on the road. Still face the many advantages of electric drive certain challenges. But: The breakthrough will come.
A major city somewhere in Germany in the coming years: Nitrogen dioxide levels are once again so high that authorities have imposed a driving ban on diesel cars. Gasoline-powered cars are also less likely to be on the road: petroleum is not an infinitely available resource, and the price of the resulting gasoline and diesel could rise significantly in the next few years or decades. Because their CO2 emissions contribute just as much to air pollution as diesel vehicles, gasoline-powered cars could also have to stop more often. For drivers, this is a problem: Commuters have to see how they get to work – and their cars have lost a lot of their value. On this day, mainly e-cars and hybrid vehicles will be rolling on the roads. They emit less or. do not emit any exhaust gases at all and therefore have a free ride. Electric vehicles will have a market share of up to 30 percent as early as 2030, says the IEA.
Climate change, oil shortages, air pollution: mobility must be CO2-neutral in the future. Electromobility makes this possible in a significant way – provided the electricity is generated from renewable energy sources. But what does the switch to electromobility actually mean and what are the consequences??
What is electromobility?
Electromobility or e-mobility is the use of electric cars, but also e-bikes or pedelecs, electric motorcycles and e-buses and e-trucks. What they have in common is that they are fully or partially electrically powered, carry an energy storage system and draw most of their energy from the power grid. Up to now, electric cars have been driven mainly in cities, and quietly, efficiently and with low emissions. They are also ideal for delivery services, cabs and car sharing.
Hybrid vehicles combine two drive technologies. Shorter distances can usually be covered electrically, but thanks to their internal combustion engine they can also cover long distances without any problems. Hybrid cars, which not only use recovered electricity when coasting or braking, but can also be charged from a power socket, are known as plug-in hybrids. Hybrids are seen as a bridging technology until the cars of the future are powered entirely by electricity.
Why is electromobility so important today??
emissions have a serious impact on the climate and the environment: Because more and more CO2 is being released into the atmosphere, the earth is becoming warmer and warmer. According to a survey by the Intergovernmental Panel on Climate Change (IPCC), transport is responsible for 24 percent of all CO2 emissions worldwide. Electric vehicles counter this trend: Unlike gasoline or diesel engines, they emit no CO2 while driving. But: Only if the production of the batteries and the electricity is based on renewable energies, electric cars are CO2-neutral in a comprehensive sense.
Low-emission cars also lead to higher air quality and thus have a positive impact on people’s health – especially in urban centers. And the number of urban dwellers will grow: By 2050, nearly 70 percent of the world’s population will live in urban regions, according to the 2014 UN World Population Report.
Fossil fuels such as petroleum, from which gasoline and diesel are derived, are not available in unlimited quantities. Exactly how long is disputed. According to the study “Statistical Review of World Energy 2017”, the oil reserves known worldwide today will last for just under 50 years at the current rate of consumption. In order for alternative forms of propulsion to become established, the purchase of electric cars is subsidized with premiums in many countries – Norway, for example, subsidizes the purchase heavily.
How an electric car works?
The structure of an electric drive
Electrical energy is stored in a rechargeable battery. Direct current to alternating current converters, known as inverters, convert the battery’s direct current into alternating current to drive the electric motor. The more effective this conversion, the longer the car runs on one charge of battery power. An electric motor eventually converts electrical into mechanical energy: The e-motor draws this energy to generate magnetic fields. A rotary motion is achieved by their attractive and repulsive forces.
The other central components of an electric car include the DC-DC converter, also known as an inverter. It efficiently converts the high voltage of the battery (100-400 volts or more) to the much lower voltage (12 or ggfs. 48 volts) for electronic components.
How is an electric car charged – and how long does it take??
Electric cars need to be plugged in to stay mobile. 80 percent of owners charge them at their home socket, according to a study by the German Association for eMobility. That takes at least eight hours, depending on the vehicle and battery. However, not every electrical outlet is designed to handle large amounts of electricity flowing for long periods of time. This problem is solved by so-called wallboxes for home use, which make charging almost four times faster. Battery charging at public alternating current (AC) charging stations takes the same amount of time, while charging at so-called direct current (DC) fast charging stations takes just under an hour. The reason for this is that the battery in an electric car must be charged with direct current, but the electricity from the public grid is alternating current. The inverter in the car first has to convert it. Charging therefore takes longer at AC charging stations than at DC stations. These convert the current already before charging into direct current and pass it directly to the battery in the car. Although DC fast-charging stations enable high charging power, they have been less common until now because they are more expensive. A special cable is required to use both charging stations. Thanks to efficient technology such as ultra-high-power chargers and improved batteries, charging times will soon be reduced to 20 minutes or less.
How much electricity does an electric car consume?
The consumption of an electric car is given in kilowatt hours (kWh) per 100 kilometers. Very small electric cars with low weight can have low consumption of less than 7 kWh per 100 kilometers. Other micro and small cars consume between 11 and 13 kWh per 100 kilometers. Electric cars from premium brands can “swallow” up to 28 kWh. Nevertheless, they can travel up to 600 kilometers thanks to particularly large batteries.
The development of electric mobility to date
Today, electromobility is considered a trendy topic, but strictly speaking it is not an invention of our time. As early as 1867, and thus before the internal combustion engine, Werner von Siemens presented his electric generator based on the dynamoelectric principle at the World’s Fair in Paris. The invention made it possible to generate electricity cheaply and flexibly wherever it was needed; it electrified everyday life, industry – and vehicles.
The first cars with electric motors were built at the end of the 19th century. The invention showed the way in the early twentieth century. Belgian Camille Jenatzy’s vehicle even set a record in 1899: It was the first road vehicle ever to reach a speed of 100 km/h. On rails rolled from the end of the 19th century. The first cars with electric motors at the end of the 19th century were railroads, which were supplied with power via overhead lines or conductor rails. As figures from the year 1900 show, electric cars were the most popular form of transport at the beginning of the 20th century. Still widely used in the early twentieth century: 22 percent of vehicles on U.S. roads had internal combustion engines, 40 percent ran on steam, and 38 percent were electric. At that time, the internal combustion engine had one disadvantage: vehicles had to be laboriously started with a crank. It wasn’t until the electric starter was invented in 1911 that gasoline engines replaced other types of drive.
From then on, e-vehicles were a niche product, but they never completely disappeared. In the mid-1990s, the Toyota Prius, a hybrid model, came onto the market. In 2008, a Californian roadster was the first e-car on the road that was also suitable for highways and longer distances.
Would you have known? The first car was an electric car!
In 1881, the French engineer Gustave Trouve presented a world first: a tricycle with an electric motor and a battery. It drove 10km/h, which was considered dangerously fast at the time. The first Benz motor car with an internal combustion engine was only demonstrated in 1886.
How fast does an electric car go today??
The following applies to all electric cars: Because they do not have a transmission, they all accelerate more consistently and faster than a gasoline or diesel engine. But what top speed do they reach? Smaller electric cars can reach speeds of up to 120 km/h. Sports cars from the USA accelerate up to 300 km/h. The fastest electric car in the world to date comes from the Croatian manufacturer Rimac: Its Nevera model races along the road at over 400 kilometers per hour.
How far does an electric car currently travel?
Most current e-cars can travel between 150 and 350 kilometers on one battery charge. So far, that makes them ideal for city driving. Only models from premium brands currently achieve more than 500 kilometers. However, the range depends on various influencing factors: Low or high outside temperatures suck up the battery, as does the use of radio or air conditioning. Constant acceleration and braking also reduce the range.
To what extent is electric mobility already in use??
Electromobility is on the rise worldwide. In 2020, 395 kilometers were driven in Germany.000 electric cars and plug-in hybrids will be purchased in 2020, according to a study by the German Association of the Automotive Industry (VDA). This puts Germany in second place worldwide. China is the frontrunner with 1.25 million e-cars and plug-in hybrids sold in 2020. The USA follows in 3rd and 4th place in the rankings with 302.000 and France with 186.000 sell e-vehicles.
Norway: the pioneer
Norway is the showcase country for electromobility: In 2017, for the first time, more vehicles with hybrid and electric drives were registered there than with combustion engines – thanks to massive subsidies. The state taxes conventional cars heavily, but there are no taxes on the purchase of clean cars. In addition, there is a low vehicle tax and free use of toll roads and state ferries. From 2025, only emission-free cars will be sold in Norway.
In addition to e-cars, more and more manufacturers are also launching commercial vehicles with electric motors that are suitable for everyday use – for example, the Mercedes e-Vito and the Renault Master Z.E., that came onto the market in 2018.
Advantages of electromobility
Electric vehicles are changing the way we get around – and not just because they are more environmentally friendly to drive. Although an electric car costs more than a comparable gasoline or diesel vehicle, electricity is cheaper than fossil fuels. This is mainly due to the costly battery production, the prices of which have fallen in recent years. But electricity is cheaper than fossil fuels. Electric vehicles also require less maintenance and are less susceptible to repairs. Oil and filter changes are superfluous; there is no exhaust system, timing belt or V-belt. An internal combustion engine has around 2.500 components that have to be manufactured and assembled, compared with only 250 for an electric motor. E-cars can be quickly serviced via “software updates over the air” or “SOTA” for short. However, this applies to all “connected cars,” i.e., cars with Internet access.
The lithium-ion batteries used in electric cars are long-lasting, have a high energy density and can withstand many charging cycles. After eight to ten years, they lose charge capacity, but they are not defective: They just store less energy. Today, most batteries in e-cars have a capacity of 20 to 60 kilowatt hours.
In the future, the batteries in electric cars will help stabilize intelligent power grids ( smart grids ). When wind and sun provide the bulk of electricity, there’s a problem: Depending on the weather, electricity supply and demand can diverge. Intelligent car charging technology will then absorb excess energy, for example when the sun is shining strongly. Conversely, it can feed surplus electricity back into the grid when it is not needed in the car. With a photovoltaic system on the roof of their house, e-car owners can be more independent of external power sources – and save themselves a trip to the gas station with a wallbox. An additional storage unit in the house can also collect the energy for times when the sun shines less.
Comparison of silicon carbide and silicon: smaller battery, higher performance
The electronics in e-cars must be powerful and efficient – they influence how long and fast vehicles can be on the road. Power semiconductors made of silicon carbide (SiC) set new standards in this respect. Silicon carbide can handle higher loads and voltages than silicon (Si) – and requires less energy to do so even at high temperatures. Thanks to the higher switching speed and lower conduction losses compared with silicon-based components, electrical power can be converted much more efficiently and compactly. The low losses also reduce the cooling requirements for the battery. This makes for higher efficiency and smaller heat sinks on the battery – it can be lighter and smaller.
Electric cars are highly efficient and much more efficient than vehicles with internal combustion engines: the ratio of supplied to usable energy is around 90 percent for electric drives. For gasoline engines it is just 35 percent, for diesel engines 45 percent. The rest is lost as heat. Other advantages: E-cars accelerate faster from a standstill because of the high torque available immediately. They can also use the DC-to-AC converter to harvest energy, for example during braking, and feed it back into the battery. This effect is called recuperation. In some countries and cities, e-cars have special rights: In Germany, for example, they park for free in Hamburg and Stuttgart, and in Dortmund they are allowed to use bus lanes. In Norway, e-car drivers have even more perks.
Since high-performance car batteries are still very expensive today, the acquisition costs of e-cars are on average higher than those of comparable combustion models. But for whom is the purchase of an electric car worthwhile?? The German oko-Institut has prepared an example calculation: At 9.000 kilometers per year and a useful life of eight years, the total cost of an e-car can be lower than that of a vehicle with a conventional drive system. You can calculate this individually on the institute’s website.
Challenges of electromobility
Despite the many advantages, electromobility poses further challenges in addition to the currently still high acquisition costs. E-cars hum very quietly. Especially in cities and along main roads, this makes it much quieter to begin with. Pedestrians and cyclists have to get used to this first. But when electric cars move at very low speeds, they are so quiet that they could be completely overheard. As of July 2019, newly developed vehicle types in the EU must therefore be equipped with an Acoustic Vehicle Alert System (AVAS): Up to a speed of 20 km/h, they must produce electronic noises similar to those of gasoline or diesel engines. If the e-car is driving faster, the rolling noise of the tires can be heard anyway. From July 2021, AVAS will be mandatory in the EU for all new electric and hybrid cars.
For e-cars to be emission-free in the broad sense, the electricity must come from renewable energies and not from coal-fired power plants, and the production of the battery must also be CO2-neutral. The use of renewable energies is also the goal of the German government: Only then can “electromobility fully exploit its environmental and climate benefits,” it writes in a dossier on the energy transition. The International Council on Clean Transportation (ICCT) determined: electric cars will overtake diesel or gasoline engines in terms of climate footprint after three years at the latest. If costly battery production becomes even more environmentally friendly, the research institute says the lead will be even greater.
The attractiveness of electromobility stands and falls with the batteries: How far can the car travel with them, how much do they cost, how much do they weigh?? There is room for improvement. The prerequisite for higher efficiencies and maximum efficiency are new technologies, such as elements made of the semiconductor material silicon carbide (SiC). The low range so far still deters many from buying an e-car, according to a survey by the consulting firm Deloitte. Yet most people could already easily use an electric vehicle for many journeys today. This is because the average German drives less than 40 kilometers on more than 80 percent of the days, explains the Federal Environment Ministry. Average Americans travel 31.5 miles a day in the fall, 26.2 miles in the winter. For Norwegians, it is about 47.2 kilometers per day on average.
Other respondents criticize the still expandable network of charging stations in Europe. Although there are currently 322.783 public charging stations, but these are distributed rather unevenly. The top five countries with the most charging stations are the Netherlands (82.263), Germany (47.076), France (45.990), as well as Great Britain (33.832) and Norway (19.119). They account for more than 70 percent of charging stations in Europe. Meanwhile, China currently operates about 800.000 public charging stations.
In the U.S., the most charging points are in California, i.e. Los Angeles, San Francisco and San Jose. So far, however, the charging infrastructure differs in different countries, and there is no uniform standard. The CharIN initiative, of which Infineon is a member, wants to change this: The efficient Combined Charging System (CCS) is to be developed into a uniform global charging standard.