It is estimated that buildings contribute 20-30% of energy use in the United States at an annual cost of over $100B. Buildings also contribute an estimated 35-40% of all US CO2 emissions resulting from building energy consumption. Any effort to decrease building energy consumption can thus have a substantial economic and environmental impact. Much of the effort invested in building energy efficiency and conservation is focused on analyzing or simulating individual physical systems within a building, to help designers understand, e.g., what savings could result by replacing standard lights with high-efficiency fluorescents, or by using light-colored paint on a building’s roof. Typical approaches combine simulating the actual physical properties of building systems, and statistical data based on historical usage. However, the complex interactions between building systems and the environment make accurate estimations difficult. The complexity of this problem increases dramatically when occupant behavior is included.
The Complexity of Building Energy Consumption