Elektromobility

The term electromobility includes issues related to electric vehicles, both for individual transport (cars and single-track vehicles) as well as mass and public transportation (busses, trolleybuses, trams, trains). These are both technical issues with the vehicles themselves as well as with the charging technologies and the necessary infrastructure. From the point of view of ecology (low carbon transport), the issue of energy sources for electric vehicles is also important.

The importance of electromobility is increasing due to the increased air pollution, which is largely caused by the use of vehicles powered by traditional fuels.

TYPES OF POWER SUPPLY
The basic division of the electric vehicles involves: the permament connection to the power grid (eg. trolleybuses), power generation with the use of devices placed in the vehicle (eg.solar buses or hybrids) and energy storage in the vehicle (battery cars, loaded through a temporary connection to the power grid). In case of the latter ones the batteries, bistratal condensers and a flywheel are used. Lately, the biggest popularity was gained by the Lithium-ion batteries because of their best technical parameters (power and relatively long life cycle).

BATTERIES

Electric vehicles have used so far different types of batteries containing different types of electrolytes, varying in capacity, viability, and price. The most popular are ion-lithium batteries and very similar to them - ion-polymer batteries.

Other types of batteries are:
- nickel-zinc
- acid-lead

CHARGING TECHNOLOGIES

Charging technologies include periodically connecting vehicles to the mains (battery charging), replacing batteries charged while the vehicle is in motion and replacing the chassis. Recently, most popular vehicles are those charged with batteries by connecting them to the mains during the time of stopovers.

Various types of electric chargers are available on the market, ranging from the simplest, home-based, and the ones with the usage scenarios basing on the exploitation of the maximum battery capacity at a certain time and then charging it when the vehicle is parked (e.g. at night), as well as those able to be charged in relatively short time (in similar time and way as refuelling at a petrol station). The charging speed depends on the power source to which the charger is connected.

The current state of development of very diverse and efficient charging technologies enables the organization of an infrastructure that equips the users of the electric vehicles with similair comfort of use as provided in conventional vehicles. This applies both to the individual and mass transport, although it also requires large-scale planning and the involvement of public authorities. This is very important for the development of electromobility. The fears about the inability to charge an electric car on the road (due to a lack of advanced charging infrastructure) is the biggest barrier for the development of the electric car market as well as the most common reason for the consumer to refrain from buying an electric car.

 

ENERGY SOURCES

From the ecological point of view, the best results brings the power supply of electric vehicles with pure RES energy. Using for that purpose the conventional sources of energy would mean that low carbon transport is powered by high carbon power plants.

From among renewable energy sources, the needs of electric vehicle chargers can be covered by the biogas plants, which provide a stable source of high power, especially for fast charging devices, similar to the refuelling of a conventional vehicle at a petrol station.

ADVANTAGES OF ELECTROMOBILITY

The most important advantages of electric vehicles are due to their neutrality to the environment as they don’t create any emissions, whereas the use of conventional vehicles has a significant effect on increasing air pollution, especially in large cities. Due to the ability to produce electricity from a variety of sources, this type of propulsion is most flexible and safe in the context of the depletion of raw materials. It also provides quiet and smooth operation, generating less vibration, which improves driving comfort and is another positive aspect of environmental impact compared to traditional vehicles.

Electric cars also have numerous mechanical advantages. They distinguish themselves by an uncomplicated design and operation with a very high energy conversion up to 90%. They allow the conversion of mechanical energy (movement) back into electrical energy and the use of this process for braking, so that the brake pads are much less consumed compared to the combustion engines. They also allow for precise control over the generated power, eliminating the conventional gearboxes and hydraulic clutches (i.e. expensive and potentially jury-rigged vehicle parts).

In many countries, the cost of using an electric car is much lower than the cost of use of conventionally powered car. It depends, however, on the energy tariffs in the area concerned. It seems, however, that from the cost point of view of the whole energy system, where the share of renewable energy sources and the charging infrastructure is increasing, it is possible to achieve much less cost-of-use of electric cars than in the traditional system.

Treating car batteries as energy stores that use the power of the grid while other receivers absorb less and use it massively would have a positive impact on the stability of the power grid, which is one of the major threats in national (and larger) energy systems

 

ELECTRIC CARS IN THE WORLD

By December 2016, the largest number of electrically charged battery-powered electric vehicles were sold in China (almost 646 000, which is about 8 000 more than in the entire European Union). According to the world ranking of electric vehicles’ sales the United States rank at the second place (537,000) and Japan at the third place (147,500). In the European Union Norway is the leader (135,000), followed by the Netherlands (113,500) and France (108,000).

In Poland, so far, these types of vehicles have not been registered, but due to the government’s plans for the development of the sector, there are very promising prospects for the future.