ENERGY SAVINGS THROUGH TREATING BUILDINGS AS SYSTEMS

Much of the analysis of the potential to save energy and reduce emissions of greenhouse gases in the buildings sector has focused on the energy savings that can be achieved through incremental improvements in the efficiency of individual energy-using devices (motors, fans, pumps, boilers, chillers) but without changing the way in which they are put together as systems. However, much larger savings are possible through changes in building systems, and further, these savings can be achieved at much smaller incremental investment cost and sometimes at lower first cost. This paper will focus on the savings that can be achieved through a systems approach to buildings. The systems approach begins with a consideration of building shape and form and the specification of a high-performance envelope so as to minimize heating and cooling loads. This leads to a number of synergies that further reduce energy requirements, such as permitting cooler temperatures for distributing heat and warmer temperatures for distributing coldness (which leads to greater efficiency in the operation of heating and cooling equipment), the use of displacement ventilation (which reduces ventilation energy requirements), and chilled-ceiling cooling (which improves the efficiency of chillers). Use of warmer temperatures for cooling also permits greater use of ambient air or direct use of coolin