Trucks are the principle means of moving goods within and between cities in most developing countries. They are therefore the workhorses of the economy. They are generally built to be durable and reliable and usually last for many years, even decades. Power and fuel efficiency are also considered important and valuable characteristics of trucks.

Because pollution control requirements on new trucks have lagged behind cars by many years, most existing in use trucks have very high emissions relative to cars. While stringent standards for new trucks are being phased in around the world, existing high polluting trucks will be around for many years unless steps are taken to address this problem.

It is important to know that newer engine technology only will work as expected if matching fuel quality is used.

The engine and emission control technologies for cleaner trucks are in principle very similar to those of conventional buses and advanced buses, (particularly where heavy duty vehicles are concerned). They include for example:

• Cleaner conventional engines meeting more stringent emissions standards.
• Advanced engine technologies based on conventional systems
• Advanced Exhaust gas emission control devices (Retrofit) (some of which require low sulfur diesel or low sulfur gasoline)
• Engines designed for the use of gaseous fuels (such as CNG or LPG)
• Certain other alternative fuels such as ethanol or biodiesel can be used in conventional engines after adaptation.

The utilization characteristics of trucks are very different from those of buses, which have important consequences for the introduction of novel technologies: city buses are centrally fuelled and large fleets are often maintained by a single operator, which makes them ideal for the use of alternative fuels and novel technologies. Trucks on the other hand often move long distances and are therefore dependent not on a specific local but a widely available infrastructure with regard to fuel provision and maintenance facilities except for centrally fueled fleets such as garbage trucks, urban distribution trucks etc.

Which approach will achieve the greatest overall, or the most desirable specific environmental improvements compared to the use of conventional diesel buses, can only be determined by means of a thorough analysis which takes all the relevant local conditions into consideration. Important factors in this context include:

• The structure of the existing truck system including such factors as the relative ratio of gasoline versus diesel; size distribution, etc.
• The availability and prices of conventional and alternative fuels

The choice of which option to use, or whether an entirely policy-based approach might be the most cost-effective option, depends on the specific situation. The Info Pool is intended to provide information relevant for such decisions, but it cannot provide the answers.

In this section therefore only low emission trucks based on conventional systems are discussed.

New trucks sold in Europe today (2003) must comply at least with Euro III regulation. New trucks sold in the USA must comply at least with EPA 98 regulation. Vehicles fulfilling these regulations are the most commonly offered on the market. Other developed countries (except Japan) in most cases relate their regulations to either Europe or USA, in some cases with a number of year’s time lag. Local emission requirements in some city centres can be even more severe than the national requirements for the rest of the respective country. In the developing countries the situation is very different. Some countries have no effective emission requirements nor/or no enforcement.