Cities & planning
Cities & planning
With the arrival of zero-emissions vehicles*, we now regularly hear talk of electric cars, hybrid engines or hydrogen-powered cars. What exactly do these terms mean and how can we differentiate them? Follow this guide.
While for many years automotive options were limited to gas- or diesel-powered engines, these days a new technology is changing the game: the electric motor. It can sometimes be used to completely replace its predecessor, the venerable combustion-powered engine, resulting in an electric car. In other cases, the two different technologies coexist within a single vehicle: these are hybrid models, which have various levels of interaction depending on the charging and energy storage systems chosen by the manufacturer.
Let’s begin with their operational differences. Electric cars are completely silent, odorless, and provide a very pleasant, smooth ride. In terms of cost, “fuel” expenses are greatly reduced, as electricity is much less expensive than gas or diesel fuel. In terms of range, much progress has been made. While just 10 years ago it was considered impressive for an electric vehicle to achieve a range of 150 kilometers, the New Renault ZOE can cover 300 km between charges. Charging is also faster than ever: with the New Renault ZOE, 30 minutes of charging are sufficient to restore 120 km** of range, depending on the charging station.
Hybrid cars have a greater range than traditional combustion-powered cars because they are gas-powered with two electric batteries as backup. Electrical power reduces fuel consumption (up to 40% of the gas generally used in urban driving situations.) When the vehicles are running on electric power, the ride is just as silent and comfortable as with a standard electric car. When the combustion engine powers the car, it feels much like driving in a traditional vehicle.
How do the different models function on a technical level? Is the optimization of energy consumption identical between the two? What are the main differences under the hoods of electric, hybrid, and hydrogen-powered cars?
Electric cars are the most advanced and most affordable solution available on today’s market to respond to environmental issues related to global warming and air pollution. What makes them unique? The combustion engine, gas tank, and exhaust pipe are all gone, and in their place you will find a battery-powered electric motor. These cars are charged at charging stations in your home, in your parking lot at work, or even in public spaces. With a potential range of several hundred kilometers, they run silently, consume no energy when stationary, and produce no exhaust fumes, not to mention the pleasant ride experience. With the new Renault ZOE, for example, all the torque of the electric motor is made available instantly, providing smooth and immediate acceleration. And finally, due to the lack of combustion and moving mechanical parts, electric motors are exceptionally reliable. For the driver, this means that maintenance is kept to a bare minimum.
There are, however, other options available. You can opt for a mix of energy sources by choosing a vehicle that combines electric propulsion and a combustion-powered engine. Here are a few of the options available, from “least” to “most” electric.
Inside a hybrid car, you will find both a gas-powered engine and an electric unit designed to work together. The idea is as follows: the electric motor serves as backup for the combustion engine, decreasing the stress on the latter and thereby lowering fuel consumption. So how are hybrid cars charged? The small onboard battery recharges during braking or deceleration by converting speed into energy. Hybrid cars still depend primarily on fossil fuels: the range of these vehicles when driven in 100% electric mode rarely exceeds a few kilometers.
Rechargeable hybrid cars, sometimes referred to as PHEVs (Plug-in Hybrid Electric Vehicles), aim to address that issue. Such is the case of the new Renault Captur E-TECH Plug-in. How does it work? A battery with a larger capacity is integrated into the chassis, and a socket is added to allow for independent charging via domestic outlets or standard charging stations. In this way, the electric motor becomes a true alternative to the combustion-powered engine for the majority of everyday travel. Nevertheless, the use of the combustion-powered engine remains an option for covering long distances, for example on road trips. The difference between hybrid vehicles and rechargeable hybrid vehicles is that only the latter can be charged at an outlet, allowing for more use of electrical power and therefore a longer electric range.
Another option is to use an electric battery and motor for everyday driving, and to add a small combustion-powered engine designed to keep them charged: this is called an extended-range electric vehicle. In this case, the hybrid is much closer to being 100% electric than 100% combustion-powered: electricity is the main source of “fuel.” For vehicles of this type, the battery has a large capacity and can be recharged at a charging station. These cars are able to run on electrical power for everyday use, without producing any exhaust fumes. The combustion engine acts only as a support, operating in a manner similar to that of a power generator. Its only purpose is to extend the range by recharging the battery, never to provide power directly to the wheels (unlike in traditional hybrid vehicles and rechargeable hybrid cars.)
Finally, there is such a thing as a 100% electric car that uses an alternative form of power: hydrogen-powered electric cars. Renault will soon be offering two hydrogen-powered utility vehicles: the Kangoo Z.E Hydrogen and the Master Z.E Hydrogen. Currently, the majority of electric cars use batteries that are based on lithium-ion technology, but there exist other ways to store energy. Hydrogen fuel cells, for example, make it possible to generate electricity from the eponymous gas, produced by the decomposition of water or methane. Within the cell, the gas is converted into electricity through a chemical reaction with the oxygen present in the surrounding air. It is fed by a tank that contains the gas stored at a very high pressure (several hundred bars).
Some obstacles still remain. The manufacture of fuel cells, for example, requires rare metals as well as an energy source, which may or may not be renewable. Large-scale adoption would also require setting up infrastructure that is dedicated to the production and distribution of hydrogen.
Electric power has made enormous strides since the days of nickel-cadmium batteries. Modern battery packs are no longer at a disadvantage when compared to combustion engines. Hidden inside the chassis, lithium-ion batteries are safe and, at the end of their life cycle, are handled through increasingly efficient recycling processes. They are lighter, more compact, and have a higher capacity, increasing the range of the cars they power. And technical progress keeps advancing: in 2019, researchers at the University of Pennsylvania discovered a new method that would allow an electric vehicle to be charged up to 300 kilometers in just 10 minutes. The technology would be good for up to 2500 charging cycles, which is the equivalent of 800,000 kilometers. Dynamic inductive charging is another promising lead, as it could enable cars to charge while in motion. Electric cars are sure to become more and more prevalent in the future!
* Zero emissions: neither CO2 nor regulated air pollutants while driving, according to the WLTP emission test cycle, excluding wear parts.
** The durations and distances mentioned here are calculated from results obtained by the New ZOE during the WLTP (Worldwide Harmonized Light Vehicles Test Procedure standardized cycle: 57% urban driving, 25% suburban driving, 18% highway driving,) which aims to represent the actual conditions of a vehicle’s use. However, they cannot foresee the type of journey after recharging. The recharging time and the recovered range also depend on the temperature, battery wear, power delivered by the charging station, driving style, and level of charge.
Copyrights : ADDITIVE, MAGROUND
Cities & planning
Cities & planning