any exemption on supply of goods to govt. ?

hello.. we are manufactures of furniture steel and wooden. we only supply furniture to military engineering service (MES) and won't sale products on private market.. is there any exemption in gst or gst rate change if goods were supplied to govt. department? tenders are
maturing and retender is going for every tenders because now rates are above TS. we are not getting work for 5-6 months because of GST. please suggest