Dehumidifiers are devices that act, either alone or in concert, with an air conditioning system to remove humidity from the air. Humidity is the measure of water vapour in the air and can greatly affect perceived temperatures. High humidity conditions can make a warm room feel hot and a hot room feel unbearable. If a dehumidifier is out of your budget, either outright or due to its high energy costs, you have a few alternatives to consider.
Central Air Conditioning
Many newer central air conditioning systems have built-in dehumidifiers that help keep energy costs down. The system requires less energy to remove moisture from the air than it does to cool the air using freon and a compressor as in an air conditioner. As such, central air conditioning units make use of a dehumidifier to reduce the humidity in the air in the house, thereby reducing the perceived temperature and increasing the highest temperature at which inhabitants will feel comfortable. Central air conditioning is a good choice if you are intending to dehumidify a large area, such as several rooms or an entire house.
Window Air Conditioning
If you are hoping to dehumidify a single room or small space, a more cost-effective option may be to run a small window air conditioner on its energy-saving option. Most newer models ship with a mode wherein the compressor runs intermittently, but a dehumidifier works to keep the moisture in the air down and increases comfort levels.
A well-insulated building can function quite well in high humidity climates simply by sealing the humidity outside the building. Increasing your insulation in the walls and attic can help reduce overall humidity in your home and thereby reduce the need for a dehumidifier. Care should be taken and an expert should be consulted, however, as improperly installed insulation can actually trap water vapour between your walls and lead to mould and mildew growth.
Many commercial desiccant options are on the market. A chemical desiccant is a small container that contains a chemical that causes water in the air to stick to its surface, usually silica. This water is then trapped in the container and can be dumped when full. In a small area with a humidity problem, such as a small unfinished basement, this may be a viable and cost-effective option.