A GAME CHANGER ENGINE?

March 2, 2011 Vol. 7, No. 5

Well, well, well... Navistar has just thrown us an interesting bone with last week's announcement that it's now involved in the development of an all-new way to power trucks, the 'OPOC' engine.

My first conclusion? It's a great time to be a gearhead truck writer.

That acronym stands for the Opposed-Piston/Opposed-Cylinder engine that's the brainchild of Prof. Peter Hofbauer, chairman and chief technical officer at EcoMotors International, based in Troy, MI. Navistar has signed a development agreement with that small outfit to help bring its OPOC engine to market.

But here's another twist: it's not an exclusive agreement. Don Runkle, CEO at EcoMotors and a General Motors veteran, says the company will announce a similar development agreement with another vehicle and equipment builder later this month. So I'll hazard a wild guess and suggest that yellow OPOC motors might well exist in years to come.

The first OPOC product targeted for commercial applications is a turbocharged diesel version, but it can actually run on pretty much any fuel except charcoal briquettes by the sound of it. Including gasoline, natural gas, ethanol, even hydrogen.

Could this be the game-changer it's made out to be? Mighty promising at the very least. Promising enough to have Bill Gates of Microsoft fame as one of two key investors, the other being Khosla Ventures’ Vinod Khosla, EcoMotors' primary backer.

So what's this wonder engine all about?

Well, let's look first at what it's claimed to offer. Like two to three times the power density of conventional engines with 50% fewer parts and at least 15% better fuel efficiency -- rising as power rises to as high as 55%! -- with attendant gains in emission levels. Its mechanical simplicity means it should cost 20% less to manufacture, I'm told. And its small stature would mean significant packaging gains and thus truck designs that could better optimize aerodynamic efficiency.

And how about this? An existing prototype pictured here, model EM100, produces 325 hp and 664 lb ft of torque, yet weighs only 296 lb. That's an astounding power-to-weight ratio of 1.1 horsepower per pound. Yet I believe it displaces just 2.5 litres. In fact, the OPOC equivalent to the 15-litre diesel of today might only be 7 litres, as I understand things.

OK, THE TECHNICAL BITS. Start by thinking about the flat, boxer engines in old Volkswagen Beetles, present-day Subarus, and, if you're old enough, the Corvairs of the 1960s. The OPOC isn't just another boxer, however. Hofbauer calls it a cross between the little VW motor and various Junkers aircraft engines that propelled an awful lot of German planes starting in 1929. In a two-stroke design, the Jumo 104 variant had six cylinders and twelve pistons in an opposed-piston configuration with two crankshafts, one at the bottom of the cylinder block and the other at the top, geared together. The pistons moved towards each other during the operating cycle and essentially formed two cylinder heads as they met. The OPOC is a variation on that theme.

There have been other engines using the opposed-piston concept, perhaps the best known being the Deltic engine built by Napier & Son in England starting in 1950. It was a two-stroke diesel used in marine and locomotive applications for many years, never a model built for trucks as far as I know. This motor was actually triangular, of all things, with the cylinders in three blocks forming the sides and with crankshafts at each point of the triangle.

Anyway, it may be no coincidence that Hofbauer conceived the OPOC engine in 1997 while working as head of powertrain development at VW, though long after its flat-four days (he designed the original VW diesel engine that became the foundation for the Jetta 'Clean Diesel' of today). Six years later a working OPOC motor existed.

Its opposed-piston/opposed-cylinder, direct-gas-exchange operation -- making it a two-stroke motor, technically -- comprises two opposing cylinders per module, with a crankshaft between them, and each cylinder has two pistons moving in opposite directions. This eliminates the cylinder head and valve train, meaning there's also no camshaft or timing chain. It may be a two-stroker, but unlike others we've known it's said to have the emissions benefits of a four-cycle design.

Those pistons move a lot faster than conventional diesels. The EM100 motor mentioned above produces peak power at 3500 rpm, for example. How come? Because the pistons have to travel only half the distance, so the engine can be run at double the speed.

ONE OF THE KEY FEATURES of the OPOC design is that the basic single engine is really a module that can be 'stacked'. A complete engine might be two or even three modules, conjoined by an electrically controlled clutch assembly housed between them. It's engaged when power demand requires both modules but when that demand drops, the clutch is disengaged and the second engine module stops completely. This will obviously improve fuel economy dramatically by reducing parasitic losses, but will also improve the efficiency of the primary module.

Another key is the electrically controlled turbocharger that puts an electric motor in the turbo assembly to regulate boost pressure. The claimed advantages include improved combustion efficiency to meet emissions mandates; precisely controlled and thus variable compression ratio; the absence of turbo lag; and enhanced driveability due to improved low-end torque.

How much more torque? At least 10% more at the low end on the tach, but it can be 'trimmed' any which way, apparently, and can even improve on that 10% at higher rpm.

In last week's press conference, Hofbauer said that development work at this stage is concentrated on combustion and fuel management in general, which are Navistar specialties.

Navistar Engine Group president Eric Tech added that the engine "has good potential" not to require SCR to meet the Environmental Protection Agency emissions mandate when it hits the street.

And when will that be?

"In two to three years we want some in the marketplace," said Dan Ustian, Navistar chairman, president and chief executive officer. Test engines will be installed in a truck and a genset later this year.

So, lots of promise, lots of claims. But, of course, the only thing we can be sure of is that we'll all be watching this one closely in the next few years.

For two interesting short videos explaining the OPOC engine, go here and here.

WHICH LEADS ME TO NATURAL GAS and things possible right now. Nowadays this fuel seems to be an ascending star. There's lots of it, it's pretty good in environmental terms, and its driving characteristics are similar to a diesel-powered truck. As well, for the moment anyway, it's cheaper.

It's obviously compelling to UPS, which just announced the purchase of 48 tractors fuelled by liquefied natural gas (LNG) The new trucks, all of them Kenworths, I believe, will be powered by Westport HD engines from Westport Innovations in British Columbia. They'll  be used in interstate operations for a regular run between Ontario, CA and Las Vegas. And that really seems to be the key here -- a regular route, a corridor, one on which the necessary fuelling infrastructure will be built or where it already exists.

Throwing a new fuel at the market is a classic chicken-and-egg thing: build the trucks and the infrastructure will come? Or build the fuel stations and the trucks will come? Take your pick, but they both have to happen at more or less the same time and it takes deep pockets like those of UPS -- ably assisted here by the U.S. Department of Energy's limitless bank account -- to pull it off.

UPS will build publicly accessible LNG fuel stations in Las Vegas and will be able to access existing sites in both Ontario and Salt Lake City, Utah, thus creating an LNG trucking corridor from California to Utah. The trucks will have a range of about 600 miles.

The courier giant now has a whopping great bunch of trucks running on natural gas, more than 1100 of them counting the new LNG tractors. the rest are package vans running compressed natural gas (CNG).

AND DITTO IN CANADA, more or less, where we see a somewhat bigger deployment of LNG tractors that also establishes a natural gas corridor. Transport Robert, based in a Montreal suburb, announced late last year it was buying 180 LNG-fuelled Model 386 and 367 Peterbilts, also running the Westport HD engine. Robert has at least one Kenworth using LNG too, pictured here.

The corridor in this case is a little more than 500 miles, running between Toronto in the west and Quebec City in the east.

Claude Robert, company president, may well be the country's most adventuresome fleet owner while running one of Canada's largest carriers. He says natural-gas technology is no longer "fringey," a word I like a lot. But his pockets aren't as deep as those of UPS. In this case, the chicken-and-egg issue was resolved by the assistance of substantial tax relief on the part of the Quebec government and the active participation of a gas company in the project. The latter will build fuel stations to make all this feasible.

SO WHAT'S LNG ANYWAY? Don't know about you, but I get CNG and LNG mixed up sometimes. They're both natural gas -- which, incidentally, accounts for about a quarter of all U.S. fuel consumption across the board -- but for our trucking purposes, they're quite different.

CNG is indeed highly compressed, in a gaseous state, but it requires six times as much space as diesel to store -- or carry -- the equivalent energy content. A major downside.

LNG, on the other hand, is cooled into a liquid form and needs tanks not quite twice the size we're used to, but they're cryogenic and thus expensive.

So LNG, it seems, is the better choice for over-the-road trucks, and the orders are starting -- repeat, starting -- to come in.

Another point worth making here is that natural gas, which is 90 percent methane, doesn't come only from fossil-fuel reservoirs. Increasingly it's coming in the form of what's called 'biogas' -- again, mostly methane -- from the decomposition of organic stuff in landfills. There are a couple of sites around the country where the trucks servicing landfills are fuelled by biogas produced in plants built right alongside. A very neat solution, and a perfect one for such fleets.

So, sure, let's explore natural gas for OTR work. But if you thought the added cost of a hybrid powertrain in a medium-duty truck was pricey, you'll think the same thing here. We're talking about an addition to the price tag of something like $40,000 to $70,000 to go greener this way.

Expensive chickens, expensive eggs. And they both cry out for continuing government leadership, government money. Or else nobody will go first.

UPCOMING SHOW NOTES...

Next week I'll be attending the Green Truck Summit and The Work Truck Show at the Indiana Convention Center in Indianapolis, IN. The 'green' event runs on March 7 and 8, followed directly by the NTEA's Work Truck Show from March 8th through the 10th.

I'm actually going to miss the ConExpo/ConAgg show in Las Vegas, March 22-26, where the new Caterpillar truck will be introduced. 

Then of course it's the big one, the Mid-America Trucking Show in Louisville, KY from March 31 through April 2.

A week later I'll be at our own ExpoCam in downtown Montreal, Quebec. It runs at Place Bonaventure on April 7, 8, and 9.

See you in a couple of weeks.

THIS NEWSLETTER IS PUBLISHED every two weeks. It's a heads-up notice about what's going on with trucking technology as well as what you can see at  www.todaystrucking.com where you'll find in-detail coverage of nearly everything that's new. Plus interesting products that may not have had the 'air play' they deserved within the last few months.

I should remind you that I don’t endorse any of the products I write about in this e-newsletter, nor do I have the resources to test them. What you’re getting is reasonably well educated opinion based on three decades in trucking. And in the case of the individual product items, I’m just presenting simple news from the manufacturer or service provider, with the hyperbole mostly removed and   clarification applied.

If you have comments of whatever sort about Product Watch, or maybe you've tried a gizmo I should know about, please contact me at rolf@newcom.ca.

FLEET MANAGEMENT

(March 01, 2011) -- Shaw Tracking launches new versions of MCP fleet-management platform

SPRAY SUPPRESSION

(March 01, 2011) -- New device integrates fuel-saving 'flap' with rugged hanger

SEVERE-SERVICE TIRE

(March 01, 2011) -- Here's a "next generation" waste-haul tire from Continental

TIRE-PRESSURE MONITORING

(March 01, 2011) -- An integrated system from Doran and PeopleNet helps take better care of tires

WET-LINE PACKAGE

(March 01, 2011) -- Chelsea wet-line systems come in convenient packages