What changed

Every correction made to an article on EnergyWise after it was published, newest first. The same note is printed under the article it changed.

  1. ENERGY STAR Label Reveals Appliance Efficiency, Not Costs

    Sources added: the ENERGY STAR certified-product lists and the EIA price table these figures were computed from; no figure changed.

  2. A median heat pump now edges a typical gas boiler this winter

    Headline corrected: at this winter's price cap the median heat pump is cheaper than a typical (84%) gas boiler by 0.09p per kWh of heat, and a 90% boiler still edges it; the old headline said heat pumps are cheaper outright.

    Headline was Heat pumps are cheaper to run than gas boilers this winter

  3. Does 1 °C lower on the thermostat save 10%? Six cities checked

    Toronto's average heating-day temperature is 3.3 °C, not 3.4; and a comparison with a published 1985–2004 degree-day total is removed, because the page it cited gives no such figure.

  4. A median heat pump now edges a typical gas boiler this winter

    At this winter's cap a heat pump needs a seasonal efficiency of about 2.97, not 2.8, to beat a 90% condensing boiler; the median heat pump (2.80) edges a typical 84% boiler by under 0.1p per kWh of heat, so 'most heat pumps' is now 'the median'. A gas standing charge you pay anyway counts for neither side; the figures are our calculation, not test data.