Our gas & electric company does free energy audits with a full sheet of recommendations. They actually came to us without me even calling this year, but I usually call for an appointment once every couple years.
In this case, our meters in our zip code were change to smart readers as a test for the entire county. They were out educating the community on the smart meters specifically and were using the same energy audit forms they use for anyone and then going over the specifics for the smart readers from other literature.
For us, the energy audit was done back in late Fall, but we still had nice weather and were still using our outside line to dry the bulky laundry and we had not turned on our furnace yet. Our furnace doesn't even come on very often since we live in a mild climate and our bill shot up $20, which is more than 20%! Obviously with our bill still under $100 a month, I am not complaining.

I am merely noting that those are the only two differences (gas furnace and drying in the gas dryer a little more). And I compare the current bill to the last month's bill (by gas usage and by electric usage) and last year's bill for the same time frame. (This info is right on our bills, but I have compared real bills, too, for more details.) The increase in our most recent bill was solely in natural gas usage, which supports my recollection of the furnace and dryer usage increase only.
I think 20+% is substantial, so that is where I would recommend focusing your efforts... heating and drying laundry.