In Germany consumers who wish to contract with independent smart meter providers are able to have one installed in their home via a similar style of subscription you might agree to for a free cellular handset from a mobile phone company.

These smart meters were monitoring their power usage in two-second intervals. They were curious what type of information they could determine about someone with such fine grained measurements.

They tested different appliances to demonstrate the unique signatures their power consumption show on the two second interval graphs. This data could identify when the refrigerator was running, when you may be home or away or even sleeping.

They then looked at electrical usage of plasma, LCD and CRT televisions and could see differences in power consumption based on the brightness levels displayed for different scenes in TV shows and movies.

You can clearly see a discernible pattern of power usage that uniquely fingerprints this film. The researchers conclude that two seconds is a bit intrusive to privacy and unnecessary for the stated goals of the smart meter companies.