Sunday, June 7, 2015

Heavy Truck Mileage

The NY Times published an article on 5/30/15 explaining how the EPA was installing a new heavy-truck chassis dynamometer in their Ann Arbor, MI lab. What is unique about this installation is the purpose it serves. Earlier this decade the executive branch tasked the EPA and DOE with implementing new economy standards for heavy-duty vehicles, as well as revising the existing emissions standards. So the purpose for the installation is principally to monitor manufacturer’s compliance with these new EPA/DOE heavy-truck economy standards. The EPA believes that by 2027 big-trucks should be getting 9 MPG. These vehicles currently get 5-6 MPG in the real world, so these projections don’t seem that far out of line.

The administration’s announcement back then also touted that the improved fuel economy would save the transportation industry money, and therefore save the consumer money at the counter. Much like corporate press releases claiming savings through reductions in force, these announcements are best viewed with suspicion. Often these same corporations are somehow stunned to find out that the people terminated actually did something more than just draw a paycheck, and the hard savings aren’t so clear. In this case when you start considering the collateral impact of these proposed economy regulations you end up doing some serious head-scratching about the feasibility of achieving these figures at all, and certainly the forecast savings this regulation will provide.

Walk with me for a while as I prattle and consider what these figures represent.

The ideal situation for a trucker is to be able to roll down the road with the rig weighing right at 80K lbs (standard interstate maximum weight). Maximizing their payload gives them the most cargo to spread their operating costs over, so they can transport our stuff more competitively. Putting a quick pencil to it, at that 80K lb. weight a truck getting 9 MPG would be burning around .0027 gallons of fuel to move each ton of weight 1 mile. That’s right, 27/10,000ths of a gallon of diesel. In comparison, your current 6000 lb. pickup truck that gets (if you’re lucky) 20 MPG is burning .016 gallons per ton/mile, or about 6X as much fuel per ton/mile as this proposed standard for heavy trucks. Thought of other ways, your average family sedan would have to get over 170 MPG to achieve this same efficiency, or your current 2000 lb. economy-car 340 MPG.

Eyebrows raised yet? Mine are.

I’m not a physicist, but to me it seems impractical to expect a traditional driveline of any type, regardless of how much it is modified, to achieve that much more efficiency in a mere 12 years. While there have been many advancements in the state of the art, the last 15 years have only netted us maybe 1-2 MPG improvement in big-bore diesel fuel mileage. In order to achieve these figures in that short of a time manufacturers will probably have to abandon conventional drivelines altogether.

To get this done I have visions of diesel-over-electric tractors (think locomotive) with large banks of rapid discharge NiMH batteries under the trailer load-floor to power the traction motors. I also see them carrying solar panels across the full length of the 53’ trailer van body roof and oh yes, carrying regenerative braking to assist in recharging the whole thing.

A fleet line-haul tractor costs $85-105K on today’s market (give or take). I'd guess a competitive new-technology tractor will cost $225-250K in today’s money. But we aren’t done there, we have a specialized trailer to buy too.  Battery and solar panel state of art are always improving, but at the electrical capacities needed I’m thinking $70-90K to cover these costs. So in the end we may achieve our 3MPG savings, but we’ve managed to spend an additional $220K per truck replacement to do it. The article estimated a $12-14K tractor price increase.

In addition to this cap-cost increase, the whole shooting-match will weigh much more because of the batteries. Figure maybe 6-8000 lbs more. This will reduce the trucker’s payload by that same amount and make his unit costs and customer costs that much higher, reducing his profitability… Sign me up now!

A lot of folks have analyzed the impact (maybe) and surely have thought about at least some of these things. But from where I sit we are suggesting that the transportation industry comply with an impractical standard. If it can be achieved at all it could cost so much that it will force smaller operators out of business, reduce market competition and cause larger carriers to rely on federal subsidies or credits to make the whole thing feasible. Squeeze all you want, a turnip only holds so much blood. 

Hello… (thump, thump, thump). Is this mic on???
  
© 2015 D.W. Williams


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