STUTTGART, Germany –More than 200 journalists from 28 countries gathered in mid-November in Germany, to be part of a two-day presentation prepared by Daimler Trucks, about its latest breakthroughs in developing “clean” commercial vehicles.

It was truly an international event because Daimler didn’t focus solely on the Mercedes vehicles commercialized in Europe but also on North American brands such as Freightliner, Sterling and Western Star, as well as its Japanese Mitsubishi Fuso brand. In fact, Daimler had taken good care to park trucks and buses from each brand in the vast parking lot of the Mercedes-Benz museum in Stuttgart, where the major press conference was held.

The leader of Daimler Commercial Vehicles, Andreas Renschler, invited journalists from every continent to make several technological announcements. Besides discussing hybrid vehicles and alternative fuels, Renschler wanted to deliver a clear political message to the leaders of industrialized countries.

And that message could be summarized in three words: harmonization, harmonization and harmonization.

There are many reasons that explain why the spreading of “greener” trucks and buses is still so slow. The main reason is probably the price issue related to the introduction of these new technologies. And it’s a little like the “chicken or the egg” question. Prices for hybrid or alternative-fueled trucks remain high because of an insufficient sales volume…and the sales volume remains restrained because the prices are too high.

The need to reach a critical mass

Of course, financial incentives by governments in the form of tax relief or other kinds of rebates, are part of the solution (the Japanese are well ahead of us on that issue). But the great diversity of regulations across the world when it comes to emissions levels and the formulation of diesel fuel represents a big problem for global manufacturers, says Daimler Trucks’ leader.

North America has its EPA regulations, while Europeans have their Euro standards and the Japanese observe their own calendar of emissions standards. This situation forces commercial vehicle makers to “customize” their “green” vehicles according to the particularities of each market, making them unable to reach a critical mass of production of harmonized clean vehicles, a critical mass that could lead to lower production prices and, ultimately, lower sale prices for cleaner vehicles.

The market seems ready, no doubt about it. For instance, Eaton has already begun to mass commercialize its hybrid systems in North America, through a number of well renowned truck manufacturers. Renschler insisted on this new reality: “We are well beyond the stage of prototypes. Our hybrid trucks and buses are very real and already into the hands of customers,” he said during a press conference. Incidentally, the Daimler brands, in Europe as well as in North America, use Eaton’s hybrid technology.

When asked by a British journalist why, in order to put pressure on politicians, Daimler didn’t form some kind of alliance with other big players in the industry, such as Volvo, to force a harmonized and global “emissions market,” Renschler replied: “Because each country defends its own interests and they are obviously very difficult to conciliate. It can only be done through collaboration, this is why I’m asking you, the media, to promote the idea to the general public.”

Environmental solutions overview

The press event was named Shaping Future Transportation and observers could see that Daimler is gunning at many targets at once in order to design and develop more environmentally-friendly trucks and buses, but also heavy vehicles that can actually save money for the end user. In fact, the chief of communications for commercial vehicles, Heinz Gottwick, had this comment: “Yes, we are committed to protecting the environment, but also to help the economy with lower operating costs.”And if, obviously, the ideal vehicle is the one with a zero emission level by using a fuel cell, all indicators state that, for the foreseeable future, diesel fuel will continue to be the main source of energy for commercial vehicles. According to an expert from Shell, Dr. Wolfgang Wanecke, hydrogen, which is a critical part of fuel cells, won’t be available in significant volumes and through a large and adequate distribution network before 10 to 20 years.

In other words, insists Renschler: “We don’t only want to replace hydrocarbons, we need to use them more efficiently.” He adds that, in Europe, the use of a urea solution has allowed truck makers to dramatically increase fuel efficiency. Truck engines burn 6% less diesel than with the previous EGR technology, about 500 gallons less per truck every year. This urea solution is mixed with the exhaust gases where a chemical reaction occurs, transforming the polluting nitrogen oxides (NOx) into harmless nitrogen and water. The process is called Selective Catalytic Reduction (SCR) and will be used by Daimler and Volvo in North America to meet the more stringent EPA regulations that will take effect in 2010. Cummins has announced that it will use the same technology, but only on medium-duty engines.

Hybrid vehicles were obviously the big stars of this event, Daimler indicating that it utilizes a parallel hybrid system (an electric motor that works in conjunction with the diesel engine) on its trucks, while on urban buses a series hybrid approach will be used (a small diesel engine works only as an electricity generator, this electricity being stored in lithium-ion batteries).

The life expectancy of these batteries is expected to be equivalent to that of the vehicle, so the user would never have to replace them. From the batteries, the electricity is transferred to wheel-hub motors, devices provided by the German company ZF Sachs. This formula considerably lowers the bus and makes it easier to board, since there is no drivetrain whatsoever.

Better yet, the wide availability of electricity makes it possible to run components such as various pumps with its power, instead of activating them with pulleys attached to the diesel engine. This added flexibility allows manufacturers to place these components wherever the engineer wants to (on the roof, for example) in order to optimize the space available in the engine compartment and on the bus itself.

Liquefied natural gas also offers some interesting results: 10% better fuel economy; 50% noise reduction; and 90% less emissions. As a matter of fact, Daimler is already converting about 10 regular gasoline vehicles a day (Mercedes cars and Sprinter delivery vans) to natural gas at its Mannheim plant that we visited.

Once again though, the distribution network issue causes a problem. As a result, these vehicles are exported to small, very well-targeted markets where access to liquefied natural gas is easier.

The first Sprinter “plug-in hybrids” are also assembled in the Mannheim plant.

After their work shift, these vehicles can be plugged into a regular electrical outlet, so a clean form of energy can fully recharge the batteries, powering them up for the next workday. The New York Times is already using prototypes of these “plug-ins” to deliver newspapers in the Big Apple.

Meanwhile, we continue to dream of zero emission vehicles that use fuel cells.

A fuel cell is an electrochemical energy conversion device.

It produces electricity from external supplies of fuel such as hydrogen (on the anode side) and oxidant such as oxygen (on the cathode side). These react in the presence of an electrolyte to produce electricity.

We had the opportunity to ride in a large articulated Citaro city bus that was powered solely by fuel cells. Very good acceleration and an extremely low noise level were noticeable.

The only thing we could hear was the sound of the compressors on the roof that are used to compress oxygen in order to produce more power. The 40-kg tanks can be refilled in
15 minutes and allow a 250 km operating range.

Heavy-duty hybrids: 6% fuel savings

We generally think of hybrid commercial vehicles as small delivery trucks used for deliveries in urban stop-and-go environments. And this is quite logical since it is the energy recuperated during deceleration that recharges the batteries. But this being said, that doesn’t mean that the owners of heavy-duty trucks cannot also benefit from this technology to save money. Daimler officials claim that a heavy-duty hybrid doing long-haul (whether it’s a Mercedes or a Freightliner) can increase fuel economy by 6% (as opposed to about 33% for the smaller city delivery trucks).

Because even though the big rigs don’t brake as often on the long highways, they climb and go down hills that force the driver to decelerate the truck. And as on every hybrid, this deceleration energy is used to produce power that allows the electric motor to help the diesel engine, making it work less.

Six per cent can seem like little for some. But if you put it in the context of a truck that runs more than 300,000 km a year, that represents a whole lot of money.

Better yet, since 110-volt power is available, you don’t need any onboard generator to provide the electricity used for driver comfort, such as heating blankets, refrigerator, microwave oven, etc. •