A direct air economizer is a type of economization strategy that allows for reduced compressor power or even complete shutdown of the compressors. It works by supplying outdoor air directly to the data center when the outdoor conditions are suitable. This is achieved by using dampers to redirect the outdoor air into the data center, bypassing the cooling coils. When the outdoor air is cool enough, it can be used to cool the data center, reducing the need for mechanical cooling and subsequently reducing compressor power.