In early October, Paris Mayor Ann Hidalgo announced a ban of all gas- and diesel-fueled cars within city limits by 2030, allowing only electric vehicles on its streets. This is another example of increasing legislation to curb carbon emissions and control greenhouse gases. The Paris announcement follows previous commitments from countries like Norway, France, the UK, China, and India in the ban of future petrol- and diesel-vehicles.
In the quest to improve fuel economy and reduce emissions to meet these increasing government regulations, global automakers have developed several powertrain options. Electrification is a strategy used by automakers to shift the vehicle from mechanical to electrical power. This move results in more efficient vehicles, by the elimination of mechanical and idling losses. Automakers have developed various levels of electrification to choose from to provide the most efficient vehicles possible.
As with any form of technology, each has its advantages and shortfalls. All of them, however, offer significant CO2 reduction opportunities to meet these changing requirements around the world. Integrating various degrees of electrification offers automakers a selection of hybrid and electric vehicle powertrain options. Today’s report will focus on the range extended vehicles. (For an overview of the various electrification options being employed today, up to and including the fully-electric, zero-emissions category, please see my previous article Electrifying Automobiles: The Multiple levels of Vehicle Electrification.)
Range extended technology may only be short term
Cars such as the Chevrolet Volt and the BMW i3 are examples of range extended vehicles (REX), which are just one step away from being considered a fully-electric vehicle. A high-capacity battery powers the electric motors which drive the wheels. Vehicles of this configuration have a small gasoline-powered ICE/generator, which engages and charges the battery as it drains to give the vehicle a few extra miles of range, with the intent of getting the vehicle to the next charging station. In the case of the BMW i3, that amounts to about 80 extra miles; for the Chevrolet Volt, its range extender unit buys its owner an extra 260 miles.
In fully-electric mode, a REX can be labeled a zero CO2 emissions vehicle, but that technology comes with a high cost. It’s considered by OEMs the most expensive option between a full/plug-in hybrid and a full-battery electric vehicle. For example, a truly zero-emissions vehicle, battery electric vehicles (BEVs), use large-capacity batteries and electric motors to power the wheels. When depleted, the batteries are recharged off the grid from a wall socket or at a dedicated charging station.
Automakers developed the REX as a BEV with an ICE/generator as a backup system to alleviate consumer “range anxiety” or the fear of running out of electrical charge before getting to the next destination and charging station.
Limited driving range has consistently ranked as a top concern among car buyers considering BEVs. Understanding this, the race for an affordable long-range electric car has been a key target for the industry. Chevy, Nissan and Tesla have long been targeting 200 miles on a single charge, thus establishing a new industry-wide target for a relatively affordable vehicle running solely on batteries.
This is why many believe the Tesla Model 3 is a tremendous breakthrough. It will have a 215-mile range. Zero to sixty in 6 seconds. Seats five adults, and carries a five-star safety rating. It costs the same as a lot of cars people buy- $35,000, and it is 100% electric.
Consider the difference between the Chevy Volt (launched in 2011) and the Chevy Bolt, which launched earlier this year. The Chevy Bolt is a pure BEV capable of going 238 miles on a single charge. The Volt, which is now utilizing 7-8 year old technology is a REX vehicle capable of going an estimated 53 miles on its plug-in charge before its small gasoline engine kicks on, turning it into a vehicle capable of driving up to a 420-mile total range. The fact that the Chevy Volt has basically dual powertrains, one electric and one ICE, makes the Volt long term, a costlier option.
More importantly, look how far battery technology development has come since 2011- a 53 mile range versus a 238 mile range today. This is why it’s expected that OEMs will steer clear of producing REX vehicles as battery technology improves, as costs of these systems dramatically drop and electric-powered driving ranges are extended.