TORONTO - If electricity bills are up for homeowners with smart meters it might be the old meter's fault -- at least that's what the Liberal government is saying.

Energy Minister Brad Duguid says the so-called smart meters, which allow people to take advantage of time-of-use pricing, are more accurate than the old meters.

Duguid says the opposition parties are misleading people when they report electricity bills have doubled since smart meters were installed in many homes.

He says bills went up because the hotter summer meant many homes used much more air conditioning than last year.

The energy minister says another less common reason bills are up is the old meters weren't billing as accurately as the new smart meters.

Duguid says preliminary numbers from people who have been on time-of-use pricing for a while now shows a slight decrease in bills.

However, NDP Leader Andrea Horwath says Duguid comes up with a new story every day to try and explain away soaring electricity bills.

Horwath says electricity bills are becoming unaffordable for many families, and calls the HST "salt in the wound" of hydro costs.