Make electric vehicles lighter to maximize climate and safety benefits: Tax heavy cars and shrink batteries to consolidate the gains from electrifying transport.

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The following submission statement was provided by /u/filosoful: — Major investments in electric vehicles are welcome news. The sector has come a long way, but many challenges lie ahead. One issue that has received too little attention, in our view, is the increasing weight of vehicles. Pick-up trucks and sport utility vehicles (SUVs) now account for 57% of US sales, compared with 30% in 1990. The mass of a new vehicle sold in the United States has also risen — cars, SUVs and pick-up trucks have gained 12% (173 kilograms), 7% (136 kg) and 32% (573 kg), respectively, since 1990. That’s equivalent to hauling around a grand piano and pianist. Similar trends are seen elsewhere in the world. Electrifying vehicles adds yet more weight. Combustible, energy-dense petroleum is replaced by bulky batteries. And the rest of the vehicle must get heavier to provide the necessary structural support1. The electric F-150 weighs 700 kg more than its petrol-powered predecessor. Smaller electric cars are heavier than their petrol equivalents, too (see ‘Heavier electric fleet’). Why does this matter? First and foremost is safety. The likelihood of passengers being killed in a collision with another vehicle increases by 12% for every 500-kg difference between vehicles. This added risk wouldn’t apply if everyone drove cars of similar heft. But until they do, the number of casualties in crashes is likely to increase as heavy electric vehicles join lighter existing fleets. Pedestrians will also be at risk. If US residents who switched to SUVs over the past 20 years had stuck with smaller cars, more than 1,000 pedestrian deaths might have been averted, according to one study. Heavier vehicles also generate more particulate pollution from tyre wear. They require more materials and energy to build and propel them, adding to emissions and energy use. How big a problem is this extra weight? A rough comparison between mortality costs and climate benefits shows that it is significant. Under the energy systems operating in most countries today, the cost of extra lives lost from a 700-kg increase in the weight of an electrified truck rivals the climate benefits of avoided greenhouse-gas emissions. — Please reply to OP’s comment here: /r/Futurology/comments/q7bden/make_electric_vehicles_lighter_to_maximize/hghcpd7/


Hilariously, emissions standards and safety requirements are one of the reasons we have such big cars. Emissions requirements are by person, so bigger cars are more forgiving. And the modern safety features are not only bulky, but often quite heavy. One always must be careful when regulating and industry- you are likely to have a lot of unintended consequences.


To me, some of the hesitation towards electric vehicles are lack of range, lack of infrastructure, and expense. Striving for smaller batteries doesn’t address any of those drawbacks. Range on a single charge is a concern, especially for those of us living west of the Mississippi. Cities and towns can sometimes be 100s of miles apart between major metropolitan areas. This ties into the lack of infrastructure. Sure, if you drive around LA, you can probably find a charging station. How about driving from LA to Phoenix, where there are large desolate areas with sparsely separated small towns. Good luck finding a Tesla charger along the way. Lastly cost, both to purchase and charge at home. Charging at home is almost exclusively a luxury for homeowners, which is a seperate can of worms. Purchase price alone, however, puts most electric vehicles out of reach of most Americans. Now imagine car companies having to invest in R&D to make denser batteries with similar efficiency. This will further drive up cost of ownership. Before we can make electric vehicles mainstream, we need to invest in better mass transit systems, change commuter behavior, and reduce the need to commute altogether (remote work).


The problem with shrinking batteries is that it would reduce range. And that’s one of the things that people worry about most, as in given the reason for not choosing electric. So you hardly want to put people off that.


This all so ridiculous. We need walking friendly cities and rail transport, no matter the massive re-development required. Cars should not be the default. It’s a shame this will never, ever be realistically considered.