You will be eligible to get tax deduction u/s 80CCG on 50% of the amount invested. Let us say, you invest Rs.50,000 under RGESS, the amount eligible for tax deduction will be Rs.25,000 from your taxable income. Let us say, you invest Rs.40,000 under RGESS, the amount eligible for tax deduction will be Rs.20,000 from your taxable income. This deduction is over and above Rs. 1 lakh limit specified under Section 80C.
In other words, for those who are in the 10% income tax bracket, savings from tax liability for investments upto Rs. 50, 000 under RGESS is Rs. 2500 (plus cess as applicable) and for those who are in the 20% income tax bracket, savings from tax liability is Rs. 5000/-(plus cess as applicable).