Next-gen Teslas have some things to prove

Hey there, time traveller!
This article was published 27/11/2017 (2868 days ago), so information in it may no longer be current.

Elon Musk knows how to make promises. Even by his own standards, the promises made recently while introducing two new Tesla vehicles — the heavy-duty Semi Truck and the speedy Roadster — are monuments of envelope-pushing. To deliver, according to close observers of battery technology, Tesla would have to far exceed what is currently thought possible.

Take the Tesla Semi: Musk vowed it would haul an unprecedented 80,000 pounds for more than 800 kilometres on a single charge, then recharge more than 640 kilometres’ range in 30 minutes. That would require, based on Bloomberg’s estimates, a charging system 10 times more powerful than one of the fastest battery-charging networks on the road today — Tesla’s own superchargers.

The diminutive Tesla Roadster is promised to be the quickest production car ever built. But that achievement would mean squeezing into its tiny frame a battery twice as powerful as the largest battery currently available in an electric car.

These claims are so far beyond current industry standards for electric vehicles that they would require either advances in battery technology or a new understanding of how batteries are put to use, said Sam Jaffe, battery analyst for Cairn Energy Research Advisors in Boulder, Colo. In some cases, experts suspect Tesla might be banking on technological improvements between now and when the new vehicles are actually ready for delivery.

“I don’t think they’re lying,” Jaffe said. “I just think they left something out of the public reveal that would have explained how these numbers work.”

Here are three of Tesla’s most provocative battery claims — and an attempt to puzzle out how they might be achieved:

Mighty truck range

When Musk took the stage in an airport hangar in Hawthorne, Calif, his first proclamation was the Tesla Semi’s range: that a fully loaded truck would be able to travel at highway speeds for more than 800 kilometres. The previous record-holder, unveiled by Daimler in October, maxes out at just over 350 kilometres.

A heavy-duty, long-range truck is the toughest vehicle to electrify while still turning a profit, said Menahem Anderman, president of Total Battery Consulting Inc., in Oregon House, Calif. Tesla may be doing it to prove a point.

“If you can make a semi truck with batteries,” Anderman said, “then you can make everything else with batteries.”

Tesla is making its trucks more efficient by reducing wind drag to levels comparable to those of sports cars. But even if Tesla achieves record-breaking efficiency for the truck, it would still require a battery capacity somewhere from 600 kilowatt hours to 1,000 kilowatt hours to deliver on Musk’s claims, according to estimates from Bloomberg New Energy Finance.

Split the difference, at 800 kWh, and it would mean a battery that weighs more than 10,000 pounds and costs more than US$100,000 — even before you build the truck around it.

Tesla has priced the truck with more than 800 kilometres’ range at US$180,000 — less than the estimated prices of seven analysts surveyed by Bloomberg — and says fuel savings will result in a two-year payback when compared to diesel.

One thing Tesla has going for it is the falling price of batteries. Musk may be banking on battery improvements between now and the early 2020s in order for its truck to make financial sense.

The first Tesla Semis won’t hit the road until late 2019. Even then, most fleet operators will want to test the trucks before considering going all-in.

By the time Tesla gets large orders, batteries should cost considerably less.

Tesla megachargers

Musk’s claim that the truck will be able to accumulate more than 640 kilometres of charge in 30 minutes would allow the Semi to achieve the first true long-haul ranges in the industry. A driver might start the day with more than 800 kilometres of range, top off the battery at lunch, and be able to complete driving the U.S. legal limit of 11 hours in a day with range to spare. But doing so would require a charger unlike anything seen before.

“I don’t understand how that works,” said Salim Morsy, electric vehicle analyst at Bloomberg New Energy Finance. “I really don’t.”

Tesla’s current generation of high-speed superchargers have a power output of 120 kilowatts and can add about 290 kilometres to the battery in a Model S sedan in 30 minutes.

But that’s for a passenger car, not a loaded truck. To meet Tesla’s claim of more than 640 kilometres in 30 minutes for a semi carrying 80,000 pounds would require its new Megachargers to achieve output of more than 1200 kW — or more than 10 times better than Tesla’s fastest chargers available today.

Guaranteed charging rates

The sticker price of any electric truck, regardless of size, is going to be higher than its diesel equivalent because of the batteries, which alone can cost as much as some standard diesel trucks. The US$180,000 Tesla Semi will compete with diesels that cost as little as US$100,000. The trick is to offset those higher upfront costs through lower maintenance and fuel savings.

Perhaps Tesla’s most head-scratching revelation is that it will guarantee truckers electricity rates of seven cents per kilowatt hour. That could result in fuel savings of more than US$30,000 a year for some, according to Bloomberg’s estimates. Musk said this will partly be done by adding solar power and massive battery packs at charging stations.

Under any scenario that Morsy expects, Tesla will be heavily subsidizing those electricity rates for customers. He estimated Tesla will pay a minimum of 40 cents per kilowatt hour, on average, for every seven cents paid by a trucking company.

“There’s no way you can reconcile seven cents a kilowatt hour with anything on the grid that puts a megawatt hour of energy into a battery,” Morsy said. “That simply does not exist.”

That may sound like a disastrous financial plan, but it’s no different from what Tesla does for its current supercharger network. Tesla offers free electricity to most of its Model S and Model X customers, while paying almost US$1 per kilowatt hour to produce it, Morsy said. That amounts to a subsidy of as much as US$1,000 per car in 2017.

Many electric utilities base their commercial rates on the peak amount of electricity a customer draws at one time, even if that peak occurs only for a brief period. Tesla’s Megacharger stations would incur extremely high charges by drawing so much power so quickly. The best chance for mitigating those charges is to build megachargers at existing truck terminals that already draw a lot of power, Morsy said, and by adding massive battery packs that can spread demand over time.

Subsidies to support megachargers could be a boon to Tesla’s balance sheet as it wades into an entirely new industry. It allows the company to maximize its upfront revenue by charging a lot for the trucks while spreading out the cost of building and operating the charging network over time.

— Bloomberg News