Ontario's Progressive Conservatives are promising to remove the 8-per-cent provincial portion of the HST from hydro and home-heating bills.
Leader Tim Hudak also says he would remove the debt-retirement charge from soaring hydro bills, which are slated to jump 46 per cent in the next five years.
The Tories say the changes would save a typical household $275 a year.
Last week, Mr. Hudak promised to scrap the Liberal government's $7-billion green-energy deal with South Korean giant Samsung and to stop offering huge premiums for wind and solar power.
Finance Minister Dwight Duncan says Mr. Hudak's HST cuts will cost the province thousands of jobs and force the Tories to close hospitals.
Mr. Hudak has already promised to let people opt out of time-of-use pricing for electricity if the Conservatives win the Oct. 6 election, calling so-called smart meters nothing but tax machines.