Why measure CO2 in garages and tunnels?
Older, pre-catalyst, vehicles generate most of the carbon monoxide pollution. To solve this, modern vehicles are installed with catalytic converters. Catalytic converters are not very efficient during cold start, but once warm they convert CO to CO₂ very effectively.
This means that modern engines emit much higher quantities of CO₂ than CO. It is a well-known fact that CO is extremely toxic, however, high levels of CO₂ is also a health hazard. To ensure healthy air quality, it is important to provide exceptional ventilation. However, running a ventilation system constantly is inefficient, especially when only a few cars are running at a time.
In garages and tunnels, vehicles might be operating in warm or cold conditions. Therefore, it is important to measure both CO₂ and CO to ensure a safe breathing environment. Current laws regarding CO state that the maximum allowed value is 35 ppm. There are currently no rules on measuring CO₂, but it is equally important.
How does it work?
A meter can control, alarm locally, and be part of a larger complete system. This application follows the same principle as required ventilation in classrooms for example.
Instead of the number of students in a classroom, the ventilation required depends on the number of cars running in a garage or tunnel. The sensors that are normally used to measure CO₂ and CO in public garages and tunnels can cover an area of around 250 m2.
In a study done in a garage containing 77 parking spaces, and covering an area of 1,445 m2, results showed that using sensors to control the ventilation reduced the fan operating time by 90% compared to constant running. The electricity cost was about 0.09 €/kWh (including energy tax and VAT) and the fan used 1.5 kWh in operation. This meant that the demand-controlled solution produced an energy saving of 970 kWh, and a resulting reduction in running costs of approximately 85 €/month.
If all residential garages were equipped this way, the sum of energy saved would generate a considerable benefit to society and the environment. A larger garage would save even more money with the controlled ventilation system.
Another benefit is fewer people suffering from CO or CO₂ poisoning being admitted to hospitals, which would reduce the costs of health care for the government.
- Public safety
- Energy savings
- Reduced costs
- Environmental savings