Benefit 1: Reduced fuel consumption and a clear head

The vehicle's occupants use up the oxygen in the air and, in doing so, generate carbon dioxide (CO₂). On long journeys with the A/C running in the circulating-air mode, the CO₂ concentration inside the vehicle starts to increase, causing drowsiness to slowly creep in and, with it, the danger of an accident.

With the Climate Control Sensor, as soon as the CO₂ level increases beyond a specific level, the CCS automatically provides a supply of fresh air. By injecting fresh air, the CCS contributes to marked increases in driving safety and comfort. At the same time, the cooled air is conserved, which leads to improved fuel economy.

Benefit 2: Reliable measurement results

The sensor uses a spectroscopic method to selectively measure the air's CO₂ content. The light from a radiation source passes through a defined path before reaching the 2-channel radiation detector. The signal from the detector's CO₂ channel changes as a function of the CO₂ concentration, whereas the signal from the reference channel remains constant. The reference measurement serves to improve the sensor's long-term stability.

Benefit 3: Future prospects

The sensor can be modified to measure other gases such as carbon monoxide (CO) and natural gas. This enables its use in other applications, such as building safety or industrial monitoring. Furthermore, coming generations of this sensor will be able to prevent rapid fogging of the windshield and thus contribute to improved driving safety by ensuring clear visibility at all times.

Applications

The Climate Control Sensor makes different applications possible:

Efficiency
The Climate Control Sensor automatically provides fresh air as soon as the concentration of CO₂ becomes too high. Maximum utilization of the already climatized air can reduce the energy consumption of the vehicle?s air-conditioning unit, which results in fuel savings. Simulations have shown that in Frankfurt, for instance, up to 19 litres of fuel can be saved per 10,000 kilometres. In Tokyo the saving amounts to as much as 48 litres per 10,000 kilometres.

Comfort
This application has to be able to recognize very small CO₂ concentrations of less than 0.2 volume percent, equivalent to the level produced by human breathing. The sensor is thus suitable for monitoring the air quality in conjunction with all types of air conditioner, ensuring a clear increase in driving safety and comfort. The sensor can, in addition, also be used to detect the presence of individuals inside the vehicle.

Safety
2011 will see the introduction throughout Europe of CO₂ air conditioners. The colourless gas CO₂ is not noticed by the occupants of the vehicle. Monitoring with the Climate Control Sensor ensures that occupants are protected against excessive CO₂ concentrations in the event of leakage. If the CO₂ concentration becomes excessive, measures such as a warning signal, automatic fresh-air input or coolant drainage are triggered.

Air Condition
The measuring of temperature and humidity provides extended regulation of the air conditioning. On the basis of information on the air temperature and humidity inside the passenger compartment, these two parameters can be adapted to provide a further improvement in comfort and safety.

Contact: climatesensors@de.bosch.com