Cool EV Capabilities

Cool EV Capabilities

Electric Vehicles are a fundamentally different approach to driving, and this opens up things that are just not possible on ICEVs, or that are easier to achieve in EVs.

Regenerative Braking

When an electric vehicle needs to slow down, it doesn’t need to use brakes. Instead of using electricity to drive rotation in the axles, the motor operates as a generator and uses rotation in the axles to generate electricity. Since it takes work to generate electricity, this slows down the rotation of the wheels (to the limit of the motor’s power), similar to how disc brakes use friction to slow down the wheels. The energy generated by regenerative braking is stored for use in driving later and increases the range of the EV. Regenerative braking can generate wheel-to-battery energy at up to 80% efficiency, and with another ~80% efficiency to use it to drive results in a net efficiency as high as 64%. Note this is compared to an efficiency of 0% without regenerative braking in traditional vehicles, as the energy is fully lost to the brake pads with heat, friction and noise.

Regenerative braking also enables “one-pedal driving”. Brakes are only typically needed for sudden stops and coming to complete stops at intersections, destinations, or in traffic. That is, brakes are only needed when the motor does not have enough power to reduce the speed of the car quickly enough. Much of normal driving does not engage the brakes, and this also greatly reduces wear on brakes as discussed in the maintenance section. You can also get higher extreme braking performance because you use both the brakes pads and regenerative braking at the same time to slow the car down.

Note that since HEVs cannot be plugged in, regenerative braking is the way they generate and capture electricity. So an HEV can be thought of as a conventional ICE vehicle with regenerative braking.

Aerodynamics

The aerodynamics of an EV are very important for range. Energy is wasted overcoming the aerodynamic drag of any car. So any improvement to aerodynamics will waste less energy and increase range.

EVs do not require a large radiator like ICEVs use to cool their engines, and they do not require an air intake like ICEVs need to generate combustion in their engines. This means significantly less air needs to be slowed down, which adds drag to the car. This is why the front of an ICEV has a much larger ‘grille’ area and air intake holes. Note that EVs still have to cool batteries and provide air conditioning which both require small radiators.

Hyundai Kona (ICEV) vs. Kona Electric (EV) front grille. (Car and Driver, 2020)

There are also opportunities to eliminate classic drag components like door handles and side view mirrors (although eliminating mirrors may require new regulations that allow cameras instead). These opportunities apply equally to EVs and ICEVs.

Noise

At idle and low speeds, EVs are quieter than ICEVs. Since no exhaust emits the sound of combustion from inside the engine, this makes sense. However, at higher speeds (above 20–30 km/h) wind resistance and tire noise quickly dominate, to the point the difference would be unnoticeable. Overall, stoplights and local traffic could end up noticeably quieter, but faster roads would sound roughly the same as they do now.

Quiet cars have a downside as well in that they pose a risk to pedestrians, cyclists and the blind. Too-quiet cars are required to emit warning sounds at low speeds to reduce this risk.

Storage Galore

EVs have more storage options than ICEVs due to parts taking up less space, in particular an emptier front bay and the lack of a driveline found in many ICEVs.

Storage space in the front end is typically referred to as a frunk (‘front trunk’). This is excellent storage for light-weight items like groceries, clothes or emergency supplies. It is not recommended to use a frunk for heavy storage as this reduces the safety bonus of having a large crumple zone.

Rivian R1T trucks have an innovative gear-tunnel behind the rear bench seating to store long items like skis, surfboards, and golf clubs. It can even be loaded with a camp kitchen as seen in the image up top.

Rivian R1T gear tunnel (11 cubic feet) that spans the width of the vehicle.

Electricity On the Road

Since your EV has a giant onboard battery pack, it can be used when not driving to provide off-grid power to all your devices. Some manufacturers are now including 110V plugs to allow any home accessory to be plugged in. This allows for tools to be used as a job site, or music and lights for a party or appliances for cooking.

EVs can also keep the cabin heated or cooled without having to idle the engine like in an ICEV. The most practical use of this feature is to get the car toasty warm in your garage before taking it out on a cold winter day, which is not possible with an ICEV due to the exhaust and risk of carbon monoxide poisoning. But this also enables fun safety features like ‘dog mode’ to keep the car at an safe and ideal temperature when leaving your dog (or child) on a cold or hot day. Or a ‘camper mode’ so you can sleep warm in the car on a cold night or connect a tent to the end of the vehicle and pump climate controlled air in.

Tesla ‘camper mode’

Always Improving

Since EVs are driven to a large degree by software, they can be improved over time and the updates can be sent to the car over data networks. These updates have had meaningful real-world impacts to performance. There have been several examples of this from Tesla, reducing braking distance by nearly 20 feet, increasing power by 5%, or adding 15 miles to range.


Next, on to Future Potential!

Header image credit: Rivian "Camp Kitchen"
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