Scoping the potential of monitoring and control technologies to reduce energy use in homes

This scoping study takes a broad look at how Information Technology-enabled monitoring and control systems in residences could play a role in mitigating energy use. Managing the residential sector is an important priority for addressing energy use, as use in homes represents 21% of US total energy demand, up 16% from 1994. Much energy is apparently wasted in delivering energy services not actually used by residents. These include heating/cooling of unoccupied houses and rooms, overheating or overcooling to make up for temperature variations, leakage current due to appliances in standby or off mode, and purchase of needlessly energy intensive models of appliances. The results of our initial rough estimate is that around 40% residential energy use is used to deliver these types of "unused" energy services. IT-enabled monitoring and control technologies have played an important role in eliminating similar kinds of waste in other sectors, so it is natural to think that these systems could have an important role in the home as well. The technology level of energy control in homes is at least 20 years old, with simple programmable thermostats still in only about a quarter of US homes. Networked thermostats, power meters and switches, and zone heating are technologies that can provide information on energy use and allow energy use to be controlled for distribution only when needed. We estimate that monitoring and control systems could save from 3-26% of residential energy use. The lower end corresponds to use of a programmable thermostat and the upper to an integrated system including monitoring and control of appliances, plus zone heating/cooling. We propose that these results provide renewed motivation to investigate the promotion of smart home energy technologies.