My husband and I live in a 1920's small brick farmhouse (1000 sq ft). Our utility bills for the previous year have been moderate from $80 - $140, then suddenly our bills jumped to 180 for two consective months. I assumed that it was the amount of A/C we were running so we turned the thermostat up to 72 from 68. We cut back on the A/C and various other things (making sure lights were turned off ect.), however even with the temp at almost 75 outside all the time and the A/C themostat set on 72 our bill was still $170. Our bill same month last year was only $80. Any ideas what could have caused this sudden surge in electric?