Minimise Leaks
Reference: Lewis et al, Design + Environment: A Global Guide to Designing Greener Goods, Greenleaf Publishing, 2001.
Energy is often consumed for no useful purpose because of leaks in the system. This is particularly applicable to heating and cooling systems, but also to others such as water and gas systems. Standby energy of energy consuming products may also be considered as leakage, and can consume more energy over the life of the product than is used in to operate the product. Large efficiency losses can result from apparently small leaks.