The load of equipments in a small shelter is about 1KWH and the atmosperic load in India can be assigned as 1KW. Fixing a 2KW Air-conditioner for a small BTS Shelter is adequate. ACs can be had from Siemens or any other reputed company. It is advisable to have a back-up cooling by PCM Energy P. Ltd. They give a passive cooling non-power system and it works wonder during power failures.