Reduce excessive heating or cooling
Space heating in winter is a big power guzzler, and the same for summer cooling for those homes with cooling systems. Use localised equipment rather than central air conditioning or heating systems, and only heat or cool occupied rooms. The room temperature should not be more than 10 degrees (Celsius) more or less than the outside/ ambient temperature. Fan or oil heaters with thermostats are best, and avoid under floor heating. In summer use a fan rather than air conditioning. But rather than use equipment at all, the best no cost saving options are things like wearing warmer clothing and using blankets in winter or opening the windows in summer.