21 Feb Why Tesla Semi Isn’t Revolutionizing the Trucking Industry
In the US, trucks contribute to 23% of all transport-related greenhouse gas emissions and roughly 6% of total greenhouse gas emissions.
Besides pressure from growing public awareness, the trucking industry is also facing increasingly stringent regulations. For example, the EPA is expected to release new truck emissions rule in 2020 and some European cities are banning diesel vehicles from entering city centers.
Switching to electrified fleets seems like a no-brainer but why hasn’t that happened yet?
In fact, Tesla unveiled its Semi truck back in 2017… what happened to it? Why isn’t it on the road yet?
Turns out, current EV technologies have quite a few critical issues that keep the electrification of commercial fleets from being viable — from operational, infrastructural, and dollar-and-cents perspectives.
Even the almighty Elon Musk can’t defy the law of physics. A closer look at the Tesla Semi will show us how current EV battery technologies are limited in their application and what we can do to make electrification viable at a commercial scale.
“It’s Physics, Yo!” = Tesla Semi Has an ROI Problem
To understand why today’s EV battery technologies aren’t viable for commercial fleets, we need to do the math to understand the fundamental issues.
Let’s start with the energy density of batteries, which is the amount of energy (kW) that can be stored per kilogram (kg) of weight. The lower the energy density of a substance, the more of it (in terms of weight) is required to store the same amount of power.
Lithium-ion batteries, which are used to power EVs, have a much lower energy density than fossil fuels (i.e., diesel and gasoline.) Therefore, you need a lot more of it to produce the power needed to cover a specific distance.
Then, we have to look at the weight equation of semi-trucks. In the US, these class 8 vehicles have a maximum weight allowance of 36 tons (approx. 36,000 kg,) which includes truck weight and payload.
To keep the total weight of a fully-loaded truck under the permitted 36 tons, any increase in the truck weight (including the weight of the fuel it carries) translates into a decrease in the payload — the part that generates profits.
Therefore, when using any battery solution with an energy density lower than that of fossil fuels, a truck needs to carry more fuel than it does currently to cover the same range. The resulting reduction in payload means the value proposition is unlikely to make business sense to trucking companies.
For example, let’s say a truck without a battery pack weighs 7 tons. That leaves us 29 tons for battery weight and payload. To cover a longer range so the truck doesn’t have to stop halfway to charge for hours (which is expensive because any minute a truck isn’t on the road is costing the trucking company money,) it’ll need a bigger battery — which means a smaller payload.
So you can either cover a greater range but carry a smaller payload or have a lighter battery pack, which requires that you sacrifice range to carry more payload.
This trade-off doesn’t make business sense when compared to diesel trucks, which can carry over 20 tons with a range of 900 miles — more than the 300-mile and 500-mile range of the two Tesla Semi variants.
Furthermore, today’s EV batteries come in a “monolithic” block — you can’t adjust the weight and size of the battery based on how far a truck needs to go on a particular trip.
While Tesla Semi’s 0-60 acceleration is impressive (but no truck driver will ever need it unless they want to get fired,) it left out a crucial piece of information that anyone in the trucking industry would want to know — what’s the weight of the empty truck (including the battery pack?)
This number will directly affect how much payload a truck can carry and therefore, how viable the business case is. The weight of the empty truck along with the cost of the battery pack will determine the exact time horizon for achieving a positive ROI.
Since the weight of the battery pack is an important factor and not much can be done to change the energy density of lithium-ion batteries, we can get a good sense of what the numbers look like if we figure out the weight of the battery pack required to cover a specific distance.
Based on one set of calculations, the 300-mile variant of the Tesla Semi will need a battery capacity of 568.44kWh and the 500-mile variant will require one with a 947.40 kWh capacity. Based on the energy density of currently available batteries, they will weigh 4.7 and 7.9 tons and cost $108K and $180k respectively.
For the 500-mile variant, the truck weight will come out to about 15 tons — leaving 21 tons for cargo, which is about the same as a conventional truck. However, just the battery alone is more expensive than a traditional truck yet it has a much shorter range. Even if the operating cost is 20% lower than conventional diesel-powered trucks, it’ll take a lot longer for trucking companies to see a positive ROI with the Tesla Semi.
Is Electric Commercial Fleet a Losing Proposition?
Not exactly! If we look at the Tesla Semi, it’s not hard to see that electrification is essential for the trucking industry and the planet. The extremely efficient engine means it will use only 25% of the energy required by a conventional truck and most of it can come from renewable sources. An electric fleet can drastically reduce the greenhouse gas emissions of the trucking industry…
…if we can solve the range problem!
BUT… it’s not about inventing new batteries or building faster-charging stations because these solutions, no matter how good, are constrained by the law of physics and the amount of power the current infrastructure can transmit.
However, there’s one way to destroy the “range vs. payload” dilemma once and for all.
Think about it. “Range” isn’t an issue when we talk about diesel trucks. It’s not because they have a bottomless fuel tank but it’s because they can be refueled quickly and back on the road to generate profits within minutes.
The range problem is only a problem when an electric truck needs to sit idle for hours to charge.
If we can bring the time required to “recharge” an electric truck to the amount of time comparable to pumping diesel into a conventional truck using existing infrastructure for handling liquid fuels — we don’t need big bad batteries.
We can reduce the truck weight to make room for more payload and generate a better ROI within a shorter time horizon.
Have Your Cake and Eat It Too
To get the best of both worlds, we need battery-powered trucks that can use renewable energy sources and be refueled in minutes, just like conventional trucks.
Instead of a monolithic battery block, the String Cells are small battery units that offer the flexibility to fuel up an EV with as much or as little power as required by each specific trip. The weight/range vs. payload equation can be optimized each and every time to maximize profits.
Meanwhile, the liquefaction technology allows us to handle the String Cells as if they’re liquid fuels (i.e., diesel and gasoline,) without having to drastically retool existing business processes and infrastructure. The refueling process involves swapping out used String Cells with new ones at a charging station — a process that’d only take 2-3 minutes.
Our system essentially allows electrified trucks to be operated as if they were diesel-powered trucks — without the environmental impact.
The Via Baltica Electrification Project is a proposal to implement an “electric highway” on a 574-km stretch of Via Baltica from Tallinn, Estonia to Kaunas, Lithuania.
Electric trucks can be outfitted with our String Tank technology and be equipped with a 400kWh battery that costs around €80,000 (approximately US$86,300.) The battery is lighter and more economically viable when compared to Tesla Semi’s battery, which is 947 kWh and costs $180,000. Because the battery is smaller, the payload can be higher (about 2,500kg more) and so is the ROI.
Meanwhile, we can leverage the existing refueling infrastructure along the route where trucks can stop and have used batteries swapped out — just like they would with diesel or gasoline.
Using Tanktwo’s system, electric trucks can be on the road for 23 hours 50 minutes a day — optimizing profitability while ensuring that businesses are future-proofed to meet the most stringent environmental regulations that are yet to come.