Science Centres: Energy

NIWA helps Auckland's big clean up

Last month, NIWA measured the exhaust emissions of about 50 000 cars in Auckland, as part of the regional council’s ‘Big Clean Up’ campaign.

When a car drives past our gear, an electronic sign tells the drivers whether their emissions are ‘good’, ‘fair’, or ‘poor’. Vehicles rating ‘poor’ were in the highest polluting 10% of the Auckland fleet, and the ARC has been writing to owners, encouraging them to tune their car. It says emissions from a poorly maintained car are 10 to 50 times worse than from a well maintained car, and getting a car tuned can save 5–20% off the annual fuel bill.

What we measure

• Carbon monoxide can prevent the blood from absorbing oxygen, and so affect your concentration. It has serious implications for people with heart or lung problems.
• Nitrogen oxides are lung irritants. They are bad for asthmatics, worsen colds and flu, and contribute to the brown haze over cities.
• Hydrocarbons are emitted by unburnt or poorly burnt fuel and leakage from fuel systems, and can include carcinogens. They also contribute to smog.
• Particulates are very small particles, mostly soot, from diesel engines. They include carcinogens.