The solar air dehumidification system permits dehydration of air inside buildings using thermal energy. With thermal energy storage it is possible to organize the continuous process of air dehumidification even in the night time. Recently we have developed low cost solar concentrators that can be used for air dehumidification. The concentrators of this type contain a large number of flat triangle mirrors. The support frame for these mirrors has a shape of a parabolic dish. The experiments with two prototypes of flat mirror solar concentrators show that a stagnation temperature of more than 300ºC can be obtained. This temperature is sufficient to regenerate almost all desiccants that are used for air dehumidification. We estimate the cost of flat mirror concentrators in mass production as 20-30 USD per square meter. This cost permits creation of dehumidification systems for residential and district applications.