When we work on energy efficiency projects, it is fairly common to talk about the “low-hanging fruit.” Often we are able to delight clients by finding energy conservation measures that are relatively low-risk and provide quick paybacks. Our experience is not unique; in fact, an entire industry has grown up providing assistance in achieving energy efficiency. The end result has been a success as shown by the most recent government forecasts for electrical energy usage show flat to slow growth anticipated through 2040.
The challenge with achieving efficiency, however, is that as we pick the easier to gather fruit, the cost and complexity of the getting the rest off of the tree is both more expensive and riskier. One case in point is lighting efficiency. The movement from low efficient T12 lighting with magnetic ballasts to T8 with electronic ballasts reduced office lighting energy usage by over 30%. Moving from conventional T8 to high-performance T8 (or to LED) offers some additional benefit but not nearly the same impact as moving from the older technology.