When hybrid vehicles were first catching on, I wondered if electrifying a semi-truck trailer would improve performance and efficiency:
Range Energy makes truck trailers, with a clever connection to any standard tractor cab, loaded with electric powertrains to turn any semi into an efficient hybrid. They also let you push entire trailers around by hand at the depot in “shopping cart mode.”
Range’s 53-foot (16-m) RA-01 trailer packs its own 200-kWh battery, as well as an 800-volt e-axle powertrain that can put up to 14,000 Nm (10,326 lb-ft) of torque, at up to 350 kW (469 hp), through the rear wheels. The same battery also feeds a rear liftgate and powered landing gear.
It works with any electric or diesel-powered cab and is perfectly suitable for fleet operations, without any modification to the trucks. It takes its cues from a smart kingpin, which basically senses the acceleration and braking loads that the tractor is putting on the trailer, and uses its electric motors to help out.
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In fuel economy testing performed by Mesilla Valley Transportation Solutions, Range reports a fuel economy boost of 3.25 mpg (72.4 L/100km) , representing a 36.9% efficiency gain against the test truck’s standard fuel consumption.
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The test was conducted on a “25.5-mile (41-km) urban/highway loop at approximately 59,000 lb (26,760 kg) gross vehicle weight and 60-mph (96.5-km/h) top speeds across multiple scenarios including stop/go and steady-speed portions.”The test was conducted on a “25.5-mile (41-km) urban/highway loop at approximately 59,000 lb (26,760 kg) gross vehicle weight and 60-mph (96.5-km/h) top speeds across multiple scenarios including stop/go and steady-speed portions.”
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Even beyond that 200-mile range once the battery is completely depleted, Range still expects about a 10-15% efficiency boost over a regular trailer for the rest of the trip, simply through the energy it can capture and release through regenerative braking.
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And then there’s “shopping cart mode” – which uses a similar control approach to let you disconnect a fully-loaded trailer from the truck and push it around manually like a hand trolley, with the electric motors helping all the way.
Now that is a really good idea, assuming the costs of the trailer are offset by the increased fuel efficiency. Moreover, the fact that the trailer is self-propelled in yard operations looks to be a major improvement in yard operations.
Now, if we get some Huawei/5G/AI optimization, like China has, we might get some big cost reductions.
The article fails to mention the weight and price of the system. It does mention that the battery pack takes 10.5 hours to fully charge. What’s the cost of the electricity, and how will the payment system work? Where will the extra supply come from, since we’re dismantling generation capacity? Who is going to install the charging stations, and where will they be? How much weight can the trailer still carry, after adding in the batteries and motors? How explosive are these batteries? What is their performance in heat and cold? What is their performance at actual highway speeds?
I’ll echo McChuck. They may be saving 36% of usual diesel fuel costs, but how much was the electricity? Plus all the externalities.
Financial benefit probably depends largely on route. If there are a lot of steep hill to go up & down, regenerative braking will have a good payback. Same thing if a lot of start-stop driving.