As the trucking industry moves into a future where electric trucks are becoming more of a reality it is sensible to remember lithium-ion batteries aren’t the only game in town. In certain vehicle applications they could well give way to so-called ‘super’ or ‘ultra’ capacitors which have the ability both absorb and release large amounts of electrical energy very quickly, particularly useful in combination with a regenerative braking system that provides a power boost for hill-climbing or starting-off. More importantly, they’re lighter compared to a battery.
Ultra-capacitors feature as the electrical-storage medium in the hybrid concept trailer developed by UK trailer market leader SDC together with French technology company Adgero. SDC’s tri-axle 13.6 metre ‘KERS’ (short for Kinetic Energy Recovery System) curtainsider features an electrically-driven leading-axle which delivers power when the semi is pulling away from rest and hill-climbing.
Four graphene super capacitors mounted between the trailer’s frame rails drive the motor/generator. Under braking, electrical energy is recaptured and stored in the super capacitors. Iconic UK fleet operator, Eddie Stobart, is trialling the KERS semi-trailer and will test Adgero’s claims of up to a 25 per cent fuel and emissions saving.
North American manufacturer Hyliion also offers a similar hybrid-trailer system including regenerative braking with its Intelligent Electric Axle. Energy from the braking system is stored within lithium ion batteries. Hyliion says the system (which can be installed in an hour) delivers an average 30 per cent fuel saving.
The system acts autonomously, reading the road and automatically propelling the trailer, no driver interaction is required nor is any training. Interestingly, the Hyliion System also becomes an all-electric Auxiliary Power Unit (APU) at rest stops providing 20 hours of power for air conditioning or other electrical needs, eliminating engine idling.