State-of-the-art review of NIALM

NIALM (Non-Intrusive Appliance Load Monitoring) is a method for gathering appliance-specific load data without individual recording meters on each appliance. The NIALM approach allows for disaggregation of total site load from measurements taken at the level of household revenue meter. Typically NIALM system determines energy consumption of individual appliances based on detailed analyses of changes in whole-house real and reactive power and voltage. These changes are called power signatures.

The state of the art of NIALM is described. First commercial product of this technology was developed in the USA at the end of last century. Development work of this technology is going on in many countries. In Finland the company MX Electrix Oy has integrated power signature recording in their power quality meter based on the specifications developed together with VTT. This new meter is called Intelligent Metering Unit (IMU).