APPLICATION NOTE 013

AUTOMOTIVE ENVIRONMENTAL CONTROL SYSTEMS

Benjamin Bacon, Owner, Plane Space Design

Even though the current state of knowledge about the future of our changing environment contains uncertainties, it is difficult to deny that the weather has been reaching extremes of both hot and cold temperatures recently. If this trend continues and if it gets worse, as many believe it will, we may be facing problems in our familiar lifestyles that will force us to change how we do things. One of the most familiar of the activities that will change is the use of automobiles. Anyone who has had enough rides in cars will know that extreme temperatures will profoundly affect how we are able to interact with our vehicles. Cars are notorious for amplifying the problems of hot and cold days to, sometimes, dangerous levels. According to a web page by Jan Null, Adjunct Professor of Meteorology at San Francisco State University (http://ggweather.com/heat/), there have been an annual average of 37 child deaths by hyperthermia in hot cars since 1998. This means that in the future there is a danger that this will increase. This bleak future for automobile occupants does not have to occur however. The Power Integrating Module with pulsed driver is a system component that makes possible a wise and effective solution to this problem. Automobile environmental control systems that can operate even when the car is not running.

The reason that most people do not use their air conditioning or heaters when a car is not running is because that will almost certainly drain all of the charge from the car's battery and leave it unable to crank. Battery technology is not going to change in the near term to make a difference in this problem. However, there is nothing that prevents the car or truck owner from using an auxiliary battery to control the environment of the vehicle when the car is not running. If it is going to get really hot, as we believe it will, then cars may become unusable if some environmental control is not provided for parked cars that are exposed to the sun. Even shaded areas may be too hot for cars to park in under the most extreme conditions. The use of a deep-cycle rechargeable battery to power an environmental control system, the air conditioner, with the engine shut off is the solution to the problem. Cars currently have one type of air conditioning installed, but they do not have all of the ingredients necessary to use this system when the car is parked and shut off. They need a deep cycle battery, a renewable energy charging source, and a switching unit to turn the power responsibilities over to the auxiliary battery when the car is shut off. The Power Integrating Module with Pulsed Driver is exactly the type of switching unit that is required.

The connection strategy is to make the switching to environmental control automatic and mandatory in the automobiles. People can easily misjudge how hot the car will get or how long they will be away before they turn the car back on. The automatic switching eliminates the possibility of a judgment error and thus saves lives and property. Automobile manufacturers can make this protection standard. The Power Integrating Module with pulsed driver is already exactly suited to the task because it operates its switching behavior on car alternator and renewable battery voltages. It also has the connections ready for implementation. It is probably the easiest solution to integrate into existing automobile electronics.

Another heat related danger is heat stroke in people who are operating a vehicle at the time of the occurrence. A car that has heated up may not cool down fast enough even with the air on if the temperature outside is hot enough. According to the the Jan Null report (http://ggweather.com/heat/), if the driver's core temperature reaches 104 degrees Fahrenheit then heat stroke may occur. Air conditioners in cars that are extremely hot, first blow hot air and then they start to cool. A driver may become too hot in the presence of a constant flux of heat into the car before the air cools enough to lower the body's temperature. The same report contains graphs that show that with external temperatures between 72 degrees and 96 degrees F vehicles can heat to 104 degrees inside in 15 to 20 minutes. A vehicle that starts at a much higher temperature and continues to take in heat while the air conditioner is on may be dangerous. A person entering a car that has been sitting for an hour in the sun goes into a 135 degree environment.

By adding the POWIM-PD to the automobile's electronics system and a source of renewable energy, the detrimental and killing effects of extreme weather on automobiles and their passengers can be eliminated. Perpetual environmental control can be applied to a vehicle without draining the cranking battery of its charge. Because the occurrence of extreme weather is a highly probable event this course of development for automobile environmental control is strongly recommended.

More Statistics and Preventative information can be found at