Efforts to curb Nairobi air pollution on right track, but more needs to be done

I recall when the late John Michuki remarked: “The plants and flowers along Uhuru Highway are black due to vehicle pollution, we must do something about vehicle emissions.” He was Environment minister then.

More than the plants, it is the impact on human health that mostly propels global efforts to reduce harmful vehicle emissions.

In mid 2000, I was a member of a chore group within the United Nations Environment Programme (Unep) called Partnership for Clean Fuels and Vehicles.
The group focused on delivering cleaner fuels and vehicles across the world to reduce harmful emissions, especially in urban areas.

In the summits I attended in Nairobi, New Delhi, Quito and Beijing, I recall commitments and efforts made to eliminate lead from gasoline; to significantly lower sulphur content in diesel while progressively working on vehicle technologies to reduce generation of harmful emissions.

A regional meeting organised by Unep and Petroleum Institute of East Africa (PIEA) in Nairobi last week gave global (and Kenya) status on reduction of road transport emissions and what remains to be done to achieve clean air objectives for our cities.

The level of urban air quality is influenced first by the quality of transport fuels, and second by the capability of vehicles to reduce emissions.

Quality of fuels is a function of refining technologies, while vehicle emissions are a function of vehicle technologies and maintenance conditions.

The leading health damaging pollutants are lead, sulphur and nitrogen oxides caused by quality of fuel. Then we have carbon by-products (black carbon, particulate matters, carbon monoxides etc) generated by poor combustion in vehicle engines.

I am here not concerned about carbon dioxide which is a product of good and complete combustion, and which is the agenda of the wider and different subject of climate change.

Kenya eliminated lead from its petrol in 2006 and by so doing significantly reduced illnesses related to lead emissions.

According to Unep, lead in gasoline has now been virtually eliminated across the world with the exception of Afghanistan, North Korea and Myanmar.

In respect of sulphur in diesel, Kenya imports diesel with a 500 ppm (parts per million) sulphur content. Diesel, previously produced from the now closed Mombasa refinery, had sulphur levels 10 times higher at over 5,000 ppm.

East African Community (EAC) standards regulators have this year gazzetted 50 ppm sulphur for diesel to be implemented by member states effective January 1, 2015. Europe is currently at a maximum of 15 ppm sulphur in diesel, and is targeting zero levels.

It is understood that Kenya will have no problem meeting the 50 ppm diesel sulphur target come January next year. However, it should be noted that lower levels of sulphur come with higher diesel price tags.

This is a necessary cost sacrifice to safeguard the health of Kenyans, especially the urban population.

Having significantly improved fuel quality, the next major effort for Kenya is to focus on vehicle emission performance, especially diesel vehicles.
Diesel engines produce harmful particulate matters (PM) mainly from incomplete and inefficient combustion.

However, the latest diesel vehicle technologies are designed for maximum energy performance and for minimum emissions.

Absence of sulphur in diesel enables these technologies to function optimally. That is why we should ensure that we meet the EAC low sulphur targets.
Most of the recently built diesel vehicles are designed for minimum emissions.

As long as we continue to effectively monitor the age of vehicle imports and achieve lower sulphur levels in diesel, we shall achieve a vehicle population that is clean.

However, local vehicle assembly plants should play a more proactive role in emissions reduction.

There are other measures we can implement to reduce the impact of vehicle air pollution. The easiest is to ensure that visibly smoking vehicles are pulled out of the roads until they are sufficiently inspected and maintained.

We need to significantly reduce pollution concentration by reducing traffic jams. We have achieved a lot through massive road infrastructure investments (highways, by-passes, link-roads etc).

Regulatory agencies

We are still not yet there as vehicle jams persist in many parts of Nairobi, made more serious by increasing number of imports.

Rationalisation of mass public commuter transportation will also help cut down emissions by reducing the number of vehicles on our roads. We should relentlessly implement the 24-plus seater buses policy while ensuring that they are equipped with improved emissions control.

We have numerous regulatory agencies which directly or indirectly influence vehicle-related emissions.

Mr Michuki, the greatest regulatory enforcer that Kenya ever had, wanted us to have clean air in our cities. In his honour, let us make it happen.
Efforts undertaken so far continue to reduce vehicle emissions in Nairobi, which is plausible.

Wachira is the director, Petroleum Focus Consultants. [email protected]