Advantages of swamp coolers:
• Swamp coolers use as little as a quarter of the energy of a standard central air conditioning system. The Sacramento Municipal Utility District estimates city residents can save about $150 per year on electric bills by switching to a swamp cooler. Savings can be far higher in hotter and drier climates.
• Some utilities and municipalities offer rebates for swamp coolers.
• Swamp coolers typically run on 120-volt power, so they can use standard outlets, rather than the separate and dedicated circuit that many air conditioners require.
• Swamp coolers should cost less to install than central air conditioners, and may require simpler ductwork.
• Swamp coolers do not use refrigerants that could be environmentally harmful. Many air conditioning refrigerant chemicals deplete the ozone layer and may contribute to global climate change.
• Swamp coolers draw more fresh outside air into the home.
• Swamp coolers are most effective at the peak heat of the day, when the air is typically driest.