Cooling and heating appliances usually account for around 50% of all energy usage in the home. Air-con and electric heaters are energy hogs with small units using 1-3 KWs and larger units up to 10KWs! Also, as they are left running for long periods of the day the costs just keep racking up. For instance, water heaters are another culprit consuming large amounts of energy to maintain water temperature. Non-LED lighting can cost large sums per year and are well worth changing with more energy-efficient LED bulbs. Washers and Dryers are next up, costing a decent amount per year due to heavy usage. Also, older households, still use less energy-efficient devices.