Embodied Energy

Embodied energy in building materials has been studied for the past several decades by researchers interested in the relationship between building materials, construction processes, and their environmental impacts. There are two forms of embodied energy in buildings:

1. The initial embodied energy in buildings represents the non-renewable energy consumed in the acquisition of raw materials, their processing, manufacturing, transportation to site, and construction. This initial embodied energy has two components. Direct energy—the energy used to transport building products to the site, and then to construct the building; and indirect energy—the energy used to acquire, process, manufacture and transport the building materials.

2. The recurring embodied energy in buildings represents the non-renewable energy consumed to maintain, repair, restore, refurbish or replace materials, components or systems during the life of the building.

Operating energy is a significant measure of sustainability which enables straightforward comparisons between alternative building technologies. Buildings consume energy for heating, cooling, ventilation, lighting, equipment and appliances. Passive energy systems rely on the building enclosure to take advantage of natural energy sources. Active energy systems represent mechanical, electrical or chemical processes. Occupants of buildings can also contribute to the heating of buildings by virtue of the heat produced through metabolic processes.