Power monitoring using wireless sensor nodes as an effective contribution to power saving in convenience stores

We installed around 17,000 sensor nodes in 2,000 convenience stores, and conducted power monitoring for a duration of between 3 months to 2 years in order to achieve 10% electric power reduction in convenience stores. From these activities, difficulties and pitfalls that lay behind “power saving measures” were discussed in general. Even when we know the value or profile of power consumption, we can't usually determine whether it is high or low because we don't have the reference value i.e., a standard level of power consumption of equipment in ever day life and work. This reference value is strongly required in order to decide whether individual power consumption is wasteful. The large scale experiments also revealed the effectiveness of a “wireless” system on electric power saving in society. Benefits and issues regarding wireless sensor node systems were investigated.