Over 70% of the energy used in the United States is consumed in the operation of buildings, whether residential, commercial or industrial. Energy efficiency measures can meaningfully reduce the energy consumed by buildings. These energy efficiency measures can even be retrofit to existing buildings, which is important since the vast bulk of energy is consumed in buildings which have already been built.
Focusing on just a small portion of the energy efficiency opportunity, several companies retrofit energy management systems (EMS) into existing smaller commercial buildings, especially free-standing restaurants and convenience stores. Current Energy is one of those companies, and our experience demonstrates that it is possible to make a substantial reduction in the energy consumption in these stores just by installing an energy management system. That reduction has averaged 10% to 20% off the average annual energy consumption before the EMS was installed. At the electricity rates that prevail in most of the country, that savings on the energy bill pays for the system in 1-1/2 to 3 years. Installing energy management systems in other types of buildings has also made meaningful reductions in energy consumption.
Retrofitting an EMS into a building is only one means of improving the energy efficiency of that building. There are a wide range of measures available to building owners, operators and occupants that can further reduce energy consumption. These additional measures frequently include changing to a more energy efficient lighting technology, repairing and reconfiguring the HVAC system (especially the ductwork), changing out to more energy efficient equipment, improving the insulation around the building shell and the HVAC system, and adding reflective coatings to windows. Beyond these are a myriad of other options that can be used in buildings to reduce their energy consumption.
Unfortunately, the Pareto Principle does not apply to energy efficiency. There is not a small set of obvious measures to add to a building that will achieve 80% of the possible energy savings. As a general rule, implementing a single energy efficiency measure creates an incremental savings. Investing in the single energy efficiency measure often creates a positive return on that investment through reduction in future energy costs, but isn’t usually enough on its own to change the economics of the building. For most existing buildings, making substantial reductions in energy consumption usually requires a broad, multi-step attack on the many causes of energy inefficiency. Improving the efficiency of existing buildings can produce dramatic reductions in energy consumption, but several measures need to be implemented to accomplish that result.
This fact was particularly true for Current Energy’s experience just with energy management systems. These systems achieve their savings by providing automated control over energy consuming equipment, usually replacing manual operation or inefficient controls. As with energy efficiency in general, no small set of new control strategies generates most of the energy savings. Rather, dramatic reductions in energy consumption can only be achieved by implementing a large number of control strategies that touch most of the energy consuming equipment in a building.
As an example of the comprehensive approach to reducing energy consumption in a fast food restaurant, Current Energy implements at least eight separate control strategies to reduce the energy consumption of the store’s lighting -- and usually more. Current Energy applies this same comprehensive approach by using a large number of distinct control strategies in managing the HVAC systems, refrigeration, hot water heater, cooking appliances and other equipment. More simplistic energy management systems do save energy with a less aggressive approach, but they can not achieve the 20%+ savings that a more comprehensive system can achieve. As one indicator of its scope of control, a Current Energy EMS typically has 4 to 10 times the number of sensor and switch connections of simpler energy management systems in equivalent stores. Current Energy continually proves that the more things you monitor and control in a building, the greater the energy savings you achieve.
There is no silver bullet for reducing energy consumption. Energy efficiency is a game of inches. Meaningful reduction can only be achieved by implementing a large number of individual measures, each of which has an incremental effect on reducing energy use, but which in total generate significant savings.
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