We describe a system to provide feedback to a user of an appliance for energy saving, the system comprising: means for monitoring an energy consumption of the appliance; means for inferring a mode of use of the appliance from said power consumption; and means for providing feedback to said user responsive to said inferred mode of use to indicate how an amount of energy used by said appliance may be reduced. In some embodiments the means for monitoring power consumption comprises means for identifying one or more periods of operation of the appliance from data representing aggregate power consumption of a plurality of devices including the appliance. In embodiments the means for monitoring the power consumption comprises means for monitoring mains electricity power consumption of the plurality of devices. Alternatively the means for monitoring the power consumption may comprise, for example, a plug- through power sensing device.