At least I’m not alone in my concern that the “smart grid” craze opens up new horizons of privacy infringement:

Smart grid technology — including new “smart meters” being attached to businesses and homes — is designed in part to provide consumers with real-time feedback on power consumption patterns and levels. But as these systems begin to come online, it remains unclear how utilities and partner companies will mine, share and use that new wealth of information, experts warn.
“Instead of measuring energy use at the end of each billing period, smart meters will provide this information at much shorter intervals,” the report notes. “Even if electricity use is not recorded minute by minute, or at the appliance level, information may be gleaned from ongoing monitoring of electricity consumption such as the approximate number of occupants, when they are present, as well as when they are awake or asleep. For many, this will resonate as a ‘sanctity of the home’ issue, where such intimate details of daily life should not be accessible.”
According to the study, examples of information that utilities and partner companies might be able to glean from more granular power consumption data include whether and how often exercise equipment is used; whether a house has an alarm system and how often it is activated; when occupants usually shower, and how often they wash their clothes.

It’s far too easy to imagine such information tempting government officials to find ways of “checking on” peculiar energy usages. Maybe that consistently high energy consumption in the basement zone of residential lot 57 is related to an elaborate toy train track setup, but maybe it’s an illegal marijuana nursery. Best to check.
And even apart from government, it mightn’t be long before targeted direct-mail campaigns begin filling mailboxes based on information learned via energy usage. No doubt detergent companies and out-of-the-home laundry services would be interested in the frequency of families clothes washing. For example.