Since long haul large tractor trucks and trailers do most of their traveling at high speed (70 mph), improved aerodynamics is important to reduce fuel consumption. However, it will not be done unless operators are convinced that they can save $$$ doing it. Nothing else really matters to them.

Making more aerodynamic cars, small trucks, buses, tractor trucks and trailers should not cost that much more, if any at all.

Higher fuel cost (taxes) could be one of the best way to convince every body to adapt.

Is this technology new? How many years have semis been on the road --- and no one has come up with aerodynamic container attachments before? Please. Shipping costs, which include fuel costs for the shippers, are ultimately passed on to consumers so the market pressures on shippers are different than retailers. I doubt shipping companies will instantly adopt this technology...if an enterprising shipping company adopts the technology and begins charging less for shipping & becomes more competitive - it might become adopted on a larger scale. Otherwise, government mandates would be required - and who wants the government doing more and regulating more at this point given the failures of the Obama administration and the democrats?

Other people have looked at adding fairings at the back for the trucks with boat tails etc.
This work would compliment it.
I suppose the trick is to make aerodynamic improvements that still allow operators to open the doors and remove the containers etc. easily.
Another thing would be to make the trucks platoon or drive automatically, so they wouldn't have to go so fast (really!).
If a human is driving, he will want to do 70+.
If a machine is driving, it will be happy to do 60 all day.

Good points ejj. Since the trucking industries can so easily pass fuel cost to customers (us), they have no real incentives to reduce fuel consumptions. Banks had a similar issue with rising house prices. The higher the better for them.

This may be a case where government intervention is required. CAFE was introduced to reduce fuel consumption (and GHG) from cars and light trucks. A similar progressive approach may be required for buses and large trucks. Fuel per tonne/miles for large trucks and fuel per passenger seat/miles for buses could be used as base factors.

You guys are forgetting about competition.

FedEx has a huge incentive to reduce operating costs because they compete with UPS.

If FedEx can reduce fuel consumption from 10 mpg to 11 mpg at a cost less than the cost of fuel - that's a huge benefit.

Just look at how the shipping companies optimize routes - for example, they typically plan routes to avoid left turns - because routes with right turns tend to get you there quicker while burning less fuel.

Re: diesel fuel prices and incentives

The government could provide low cost loans/loan guarantees to Class 8 truck operators. The government could also provide fund matching for a company like BMI, up to a certain amount, for investment in a domestic manufacturing facility to produce the components. Then, to incentivize the switch, the government could raise the tax levied on diesel fuel which would recover any outlays made by the government.

The net result would be lower fuel consumption domestically which would mean fewer dollars flowing out of the country to buy oil. The consumer would end up having more buying power as fuel would be less expensive/more available on the world market which would lower the cost of certain imports.

Alternately, the government could use the fuel tax revenues to add to the Strategic Petroleum Reserve. This would keep prices high while assuring that fuel consumption is lower (no "leakages" where the fuel is used in other economies) and it would give us an additional cushion in the event of war or a market that has gone haywire.

With all of that said, I'm largely opposed to government intervention (seriously, I am). The government created the housing mess with Fannie and Freddie by keeping interest rates artificially low. Tons of externalities have resulted from this including a less mobile (and therefore more easily exploited) workforce. I would much prefer a company like Exxon or Chevron to use their piles of cash and political clout to move forward simple energy conserving devices such as fairings on Class 8 trucks.

Exxon/Chevron could retrofit the entire U.S. class 8 truck fleet without breaking a sweat. How do they make money? Rent the fairings out or offer a fuel discount for trucks that use the fairings. Companies like Exxon/Chevron need to stop being oil and gas companies and start being energy companies (Chevron is on to this already to a small degree).

If you've been on the roads much lately, you've probably noticed that lots of semi-trailers are sporting aerodynamic skirts down the sides. The system of front tray, axle and diffuser fairings would appear to be an incompatible scheme. The full side fairings have the virtue of keeping the slipstream from striking the trailer wheels directly, so I would not be surprised if they are more efficient.

The gutter and side fairings work with either. What might help is a truncated inflatable boat tail mounted to the trailer doors, perhaps with active control of the airflow around the transition to achieve minimum base drag.

This technology shows just how critical the airflow under a vehicle is to its coefficient of drag. It's a good start.

In the long term, what's needed is a complete rethink of the semi-tractor trailer.

Except for bulk cargo, the shipping container has come to dominate long distance transport. A shipping container is a structural beam made to carry its own load. It does not require a trailer.

If a semi tractor were to grapple on to the front of the container, with a trailing axle behind the container, the whole unit could be dropped by three feet, reducing frontal area by 25 square feet and also reducing the quantity of air flowing under the rig. Hydraulics could be used to raise the trailer to dock height.

This would also reduce the number of moving parts requiring maintenance. The container would be left bare with its axles and wheels being "borrowed" from the tractor.

In the next step, tractor locomotion could be shifted to a battery-buffered concept utilizing super-efficient, slow-turning, long stroke marine style diesels. Short-term high power demand would be handled by battery storage, with the diesel running continuously over a narrow power band. Drive would be by hub motors on all axles. Since the trailer's axles are provided by the tractor, this system would be workable without excessive increase in cost.

Re: "a shipping terminal is a very busy place and there's little time to spare for unloading the rear wheels from the back of the tractor unit"

That's true. However, the whole process could be automated with hydraulics.

Some years ago I rode on a logging truck hauling tree-length pulp wood. The "trailer," consisting of a long tube with the back axles attached, collapsed and folded up, the entire assembly resting on top of the fifth wheel when in transport position. The whole thing was handled with hydraulics. The driver did not have to get out of the cab.

Something similar could be designed, automating the hook up process. Another advantage of such a system is the lower center of gravity. I once rolled a fully loaded grain truck when I backed one side into a big pot hole I couldn't see. It's no fun.

MahonJ,

Truckers are paid by the mile. More miles/hour = more $/mile. So, naturally, they want to go as fast as possible.

Also, count in the fact that they're only allowed to be "on duty" for a certain number of hours within a week, within 24 hours, etc. For more specific information, see:

http://www.fmcsa.dot.gov/rules-regulations/topics/hos/index.htm

Consequently, if they're doing 60 instead of 70, that limits how far they can go before they have to pull over and rest.

For many routes, that's the difference between delivering in 14 hours and delivering in 24+ hours (with a mandatory break along the way) or delivering in 38 hours vs 48+ hours (60 mph * 14 hours = 840 miles; 70 mph * 14 hours = 980; rules require <= 14 hours on + >= 10 hours off in any 24 hour period). Consequently, reducing speed results in shipments taking significantly longer to arrive (not in the shipper's best interest) or drivers bending the rules and getting "creative" in their log books (not in the best interest of others who are sharing the road with that truck).

Shipment companies are hesitant about imposing corporate speed limits, but some of them do. SWIFT trucking routinely puts governors on their rigs. That's why many drivers refer to them as Slow Wagons In Fast Traffic or Sure Wish I had a Faster Truck.

No, I'm not an OTR driver. My dad was. His company toyed with putting governors on their trucks. Lower speed = higher fuel mileage, after all. Once dad explained that the proposed governor setting would result in this trip taking 25 hours vs 14 (because the lower speed would result in a mandatory rest period between pickup and delivery + another hour of travel time) and other variations on the theme, they backed off.