Truck & Off-Highway Engineering - June 2021 - 13

EXECUTIVE VIEWPOINTS
Since acquiring the e-axle IP from AxleTech in
2019, Allison engineers have put the product
through extensive development and validation.
by increasing the efficiency of the electric powertrain,
there will be a motivation to accelerate the
changeover process.
Many of the big fleets have shared how they want
their fleet to look 10 or 20 years from now. That's a
huge influence on how the market will develop, especially
given the size of some of the larger fleets. They
will motivate the OEMs, which in turn will look to Tier
1s to bring these products forward. We are already
seeing developments in small-package and last-mile
delivery fleets. With a boom in e-commerce, new
OEMs and new types of vehicles are emerging.
The speed at which commercial EVs will switch over
to electric power will differ from segment to segment,
and from region to region. Some segments, notably
transit, are moving faster than others. In North
America, developments in medium-duty pickup and
delivery will start to gather speed. The school bus sector
is starting to move early, as are many port truck
applications. All these sectors are looking to clean up
areas where a high percentage of vehicles operate in a
very a confined space.
The switchover also is happening in areas where
subsidies and legislation are acting as a motivator for
adoption. In Europe, for example, there has been
movement towards hydrogen in some of the over-theroad
tractors, which differs from North America currently.
The trends will continue to evolve as infrastructure,
subsidies and funding get put in place - anything
that reduces the cost of adoption - so we need
to be mindful of where those motivators are as we
assess market opportunities.
Hydrogen and hybrids
When it comes to widespread use of hydrogen fuel cells,
the progress of infrastructure will influence the long-term
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cost of fuel cells versus BEVs. As it stands today, the larger over-the-road
applications seem to be a better fit for a fuel cell, as adding battery
weight to extend range eats into the payload. For long-distance runs, the
shorter refueling time also works in the fuel cell's favor.
In the meantime, we shouldn't ignore the role that hybridized ICEs
could play. Where they thrive will be driven by emissions regulations
for NOx and other greenhouse gases. BEV or ZEV zones will require
emissions-free running, but emissions must also be reduced on the
operational side. There's definitely a place for the hybridization of
conventional products to meet some of those regulations in the near
to even the long term.
Diesel is going to be around for a very long time, so how do we continue
to improve it and allow it to play its part from an emissions perspective,
while BEVs or fuel-cell electrics have a slow ramp up? The hybridization
of conventional propulsion systems is an opportunity to meet some
of the regulatory items without a significant overhaul of the vehicle.
Michael Foster, Chief Technology Officer for Allison Transmission, wrote this
article for TOHE as part of the annual Executive Viewpoints series.
June 2021 13
FROM TOP: ALLISON TRANSMISSION; SAE INTERNATIONAL
https://www.sae.org/publications/books/content/r-494/
Truck & Off-Highway Engineering - June 2021

Table of Contents for the Digital Edition of Truck & Off-Highway Engineering - June 2021
