The roll-out of smart meters in developed nations is being met with resistance from many quarters – those suspicious of health consequences, reluctant to embrace digital technology, unconvinced by the supposed benefits, or simply obstinate in the face of pressure from energy providers. There are also many who question what outsiders could learn from looking at their family’s consumption data.

Last month, a US Court of Appeal in Naperville Smart Meter Awareness v. City of Naperville affirmed an earlier decision to protect such data under the 4th Amendment, holding that individuals have a reasonable expectation of privacy in regard to energy data, and that the government would be effecting a ‘search’ if it looked at any smart meter data.

This news comes as IoT devices are being introduced into a majority of Western homes, meaning that smart meter data can increasingly reveal not only when specific devices are being switched on and off, but how a particular device might be being used, and even by whom. Meanwhile, advanced software is able to make increasingly accurate and diverse deductions about a person’s lifestyle from their long-term energy usage. It all adds up to a valuable data harvest that commercial interests would readily buy up.

Privacy International wrote:

Aggregate smart meter data collected from someone’s home in 15-minute intervals could be used to infer, for example, whether they tend to cook meals in the microwave or on the stove; whether they make breakfast; whether and how often they use exercise equipment, such as a treadmill; whether they have an in-home alarm system; when they typically take a shower; if they have a washer and dryer, and how often they use them; and whether they  switch on the lights at odd hours, such as in the middle of the night. And these inferences, in turn, can permit intimate deductions about a person’s lifestyle, including their occupation, health, religion, sexuality, and financial circumstances.

In the most recent Naperville decision, the Court said that smart meter data “reveals information about the happenings inside a home” and that the “ever-accelerating pace of technological development carries serious privacy implications,” with smart meters being “no exception”.