Gas for green

Unitrans, in partnership with Mercedes-Benz and Sasol, has launched a pilot project for the use of environmentally-friendly liquid petroleum gas (LPG) in its fleet. GAVIN MYERS reports.

The world is moving to greener, more sustainable transportation. Europe is ready and waiting for Euro-6 legislation to be implemented during the course of 2012 and, as you’ll read elsewhere in this issue, Brazil is set to introduce Euro-5 legislation on January 1, 2012 for example. Yet, South Africa lags behind. Our legislation calls for a minimum emission standard of Euro-2 and our widespread 500 ppm diesel does not allow for more advanced emission-reducing technology.

It is therefore left up to proactive companies to take the lead in this regard. We have already seen many Euro-5 spec vehicles being specially requested from various manufacturers for this purpose. But there is another alternative, as Unitrans Supply Chain Solutions, Mercedes-Benz Commercial Vehicles and Sasol Oil are demonstrating.

A first-of-its-kind initiative undertaken by a southern African supply chain specialist and large fleet operator on a heavy duty vehicle, this joint project will pilot the use of liquid petroleum gas (LPG) as a cleaner alternative to diesel. For the next six months, a Mercedes-Benz Actros 2644 LS/33 truck tractor will be put into operation at one of Unitrans’ national customers in KwaZulu-Natal to test the LPG system. Depending on the results, Unitrans will consider converting more of its fleet to LPG fuel.

The vehicle is fitted with a Voltran Version 3 gas-injection system, enabling it to run on a mixture of up to 40% LPG and 60% diesel. Combined with the Actros’ Euro-3 compliant 11,9-litre V6 engine, this results in the vehicle’s CO2 emissions being potentially reduced by up to 12%. Further reductions of hydrocarbons, particulate matter and smoke outputs are expected, potentially reducing them to levels equal to those of a Euro-5 vehicle.

The Voltran Gas Conversion Kit fitted to this vehicle is designed and manufactured in Germany. The engine operates as normal, but individual gas injectors in each cylinder deposit the exact amount of LPG for any set of operating conditions, as per the electronic control unit. This sequential fuel injection system is said to be among the most technically sophisticated available for the operation of diesel and LPG. The engine can be operated with either a diesel/LPG mix, or with diesel only.

Fitted with a side-mounted 250-litre
80 kg special LPG container (that can only be filled to 80% of its capacity while in use), the vehicle’s standard fuel tank had to be replaced with a smaller 320-litre tank, but is combined with a 280-litre reserve tank. The gas tank is manufactured to meet European safety standards, being individually pressure tested and stamped.

The LPG will be supplied by Sasol from the Unitrans depot in KwaZulu-Natal and from Sasol’s Retail Convenience Centre in Kempton Park, while the Mercedes-Benz FleetBoard system (standard on the Actros) will provide the tracking and monitoring of the vehicle’s total performance.

“The conversion of the Actros 2644 to LPG is another example of how we actively listen to our customers, look for a solution and find a suitable partner to make it happen,” says Kobus van Zyl, vice-president of commercial vehicles at Mercedes-Benz South Africa. “The innovative thinking of the management and operational staff of Unitrans is to be commended, and we hope that we, too, will be able to offer a number of options of environmentally-friendly vehicles in South Africa in the not too distant future.”

Unitrans’ Ray Singh continues: “Unitrans’ trucks are by far our greatest contributor to our carbon footprint. With a fleet of around 2 500 trucks operating in Southern Africa every day, we have a substantial impact on the environment and an even bigger responsibility to become part of the solution in the fight against climate change.”

“This truck represents the first solution where our technical team was satisfied that its CO2 emissions would be reduced for the duration of its life, without compromising its operational capabilities,” Singh concludes.