Largest electric vehicle in the world does not need to be charged
The roughly 110-ton dump truck (fully loaded) runs purely electrically and thus helps around 130 tons of CO2 or over 50,000 liters of diesel annuallysave. In each quarry in Biel, Switzerland, the eDumper transports around 60 tons of limestone and marl rock from the higher-lying mining area to a lower-lying transport system. The eDumper is electrically powered for empty travel uphill.
Downhill, the lithium batteries recharge due to the recuperation of the braking energy and thus generate more than enough charging current for the return trip. Due to the 13 percent gradient, the eDumper only comes to its destination with a brake when fully loaded. The eDumper produces around 200 kWh around 20 times a day, which results in an annual surplus of around 77 megawatt hours after subtracting the vehicle’s drive energy and the operation of the cooling systems and hydraulic pumps, which should not be underestimated, and is fed into the public power grid.
The world’s largest electric vehicle on wheels is the new dump truck eDumper. Due to the special area of application and the local conditions, this electric vehicle does not have to be charged on the power grid and even feeds around 77 megawatt hours into the power grid every year.
The electrical change affects not only electric cars , but also various other vehicles such as ships and planes . But other means of transportation, such as dump trucks, can also be electrically powered – as the eDumper from Switzerland impressively demonstrates.
Although electric vehicles are considered to be locally emission-free, one should not forget the emissions from power generation in the power plant . That’s why an electric car is actually only as clean as the charged electricity. The production of lithium-ion batteries is also very energy-intensive. A new electric car begins its life cycle compared to a combustion car with an “ecological backpack” , the size of which depends on the battery capacity.
The ADAC study on the overall CO₂ balance of different drive types shows that an electric car still does better than a car with an internal combustion engine. The German electricity mix is used as the basis for the calculations. If a vehicle were charged 100 percent with electricity from renewable sources such as wind power and photovoltaics, the CO₂ emissions would be extremely low during operation (CO₂ value of wind power approx. 20 g / kWh). Due to the increasing share of renewable energies in the German electricity mix, the balance continues to improve in favor of the electric car.
Batteries weighing four tons:
A 600 kWh lithium battery is built into the eDumper itself, which weighs over four tons. The performance corresponds exactly to that of six Tesla Model S in the largest version with a calculated range of around 3,680 kilometers. However, the batteries in the eDumper are much heavier and only last for short distances, because the dumping tip is not a high speed but a high torque.
The heart of the electric car is the battery . Other components are the electric motor , the power electronics as well as the cooling systems and the temperature management. Units such as steering, braking device and heating / air conditioning are operated electrically.
The so-called “skateboard” architecture has prevailed in the arrangement of the components in the vehicle : battery between the axles in the underbody, electric motor and power electronics on the front and / or rear axle. The body is put over this skateboard, so to speak. This so-called underfloor architecture is intended to enable a somewhat better use of space than in vehicles with an internal combustion engine.
Braking and Driving Downhill:
When braking and driving downhill , the electric motor becomes a power generator and recovers energy ( recuperation ). By driving ahead, an electric car can be driven almost without the use of the mechanical brake, which means that the brake lasts longer.
Because electric motors are quiet, it can happen that slow-moving electric cars may not be heard or may be heard too late. This leads to “moments of shock” for pedestrians, for example in parking lots or in traffic-calmed areas. Since mid-2019, new electric cars have had to be equipped with a sound generator as standard, which generates an artificial (warning) noise up to 20 km / h. As usual, electric cars are perceived via tire noise.
The electric motor: driving comfort and efficiency:
The electric motor was patented as early as 1837/38. Since then, it has been used in innumerable areas in industry, crafts and mobility (electric rail). And it proved itself as the ideal drive machine – extremely efficient when it comes to energy: reliable , low- wear , almost noiseless and vibration-free . With an electric motor, full torque is available from the start over a wide speed range – which is why a gearbox with a fixed ratio (only one gear) is sufficient for most applications.
In particular, the driving comfort of the low-noise drive without the hassle of changing gears and the driving fun due to the spontaneous torque development inspire many drivers on their first trip with an electric car. An electric motor works with an efficiency of over 90 percent and has only a few losses in the form of heat or friction.
The big challenge, and at the same time the reason why the electric motor could not prevail against the internal combustion engine for use as a drive motor in motor vehicles at the beginning of the 19th century, was energy storage – that is, to achieve acceptable ranges.
Battery: Manufacturing still complex and expensive
The production of traction batteries still costs a lot of energy and is still relatively expensive – although battery prices have already halved since 2013. Even if solid-state batteries are traded as energy storage of the next generation, according to experts, there is still potential in lithium-ion batteries. With advancing technological development and increasing battery quantities, both falling battery prices and improvements in energy density can be expected.
Lithium-ion battery: energy, safety, durability:
Energy and durability
The most important requirements for the battery of an electric car are high energy and power density (important for driving performance) as well as safety and functionality. Almost all vehicle manufacturers and suppliers are currently concentrating on the lithium-ion battery, since it best meets the requirements and also has development potential.
Lithium-ion batteries are also characterized by high cycle stability (charge / discharge). For some time now, they have been the standard equipment for small electrical devices such as cell phones, notebooks and cordless tools. In contrast to the lithium-ion batteries installed there, the batteries used in the electric car have sophisticated thermal management. This ensures a long lifespan for the battery cells. On the one hand, it ensures that the cells do not overheat and, on the other hand, controls the temperature control and the power output in the cold so that the cells are not damaged.
The comparison with an organism is obvious: If the battery is not kept in a certain temperature range , it does not feel comfortable and cannot work well or is even damaged. Power density, energy density and cycle stability have been successively improved in recent years. Current electric cars have twice the battery capacity as six years ago – with the same size .
The electrical components of mass-produced electric cars are designed to be intrinsically safe . In normal, intended use, these electric cars can therefore be considered safe .
It can become critical if the technical protective measures of the drive battery have been deformed by an accident and have thus been impaired. In the worst case, the cells in the drive battery can “run through” – the so-called “thermal runaway”. The burning drive battery must then be extinguished with plenty of water.
A defective drive battery can be very expensive, comparable to engine damage in a combustion car. With the electric cars currently available, a modular repair of the battery is basically possible in most cases, although not always possible in the workshops. In this respect, one should pay attention to the battery warranty periods of the respective manufacturer and inquire whether and at what cost a partial exchange of battery modules is possible.