CHENNAI: A comparison of power tariffs across the country shows that 18 states charge consumers higher than Tamil Nadu, even after the recent tariff increase.According to data accessed by TNIE, in Rajasthan, consumers have to pay Rs 935 for the first 100 units and Rs 1,583 for 200 units. But the first 100 units are free in TN and it is only Rs 225 for 200 units.