An air cooler improves the quality of air in your space due to the way it works. So much so that persons with asthma or dust allergies prefer the air circulated by an air cooler. When it comes to value for money, an air cooler clearly outperforms an air conditioner. An air conditioner uses a refrigerant called "CFC" or chlorofluorocarbons. These chemicals have been linked to global warming. They also deplete ozone pollution levels. Air conditioners are very expensive to run and emit harmful gases like carbon dioxide and water vapor. Electric powered air conditioners are more environmentally friendly but they are also more expensive to buy and operate. An air cooler does not use a chemical refrigerant and therefore has less environmental impact. It is also cheaper to run (because it doesn't need to be recharged as often) and produces less carbon dioxide. However, it does still use electricity and some models require changing of the filter regularly. This is because contaminants such as pollen or bacteria build up in the filter over time and need replacing. It's difficult to compare the values of air coolers and air conditioners directly because they work differently. An air cooler spreads out warmth from people's bodies and reduces the temperature of the room. This makes it better for people who are allergic to heat or want to keep their room at a comfortable temperature even when they aren't home.