The gray energy is the quantity of energy necessary for the production and the manufacture of materials or the industrial products. In theory, an assessment of gray energy adds the energy spent at the time:

• of the Design of the product or the service

• of the Extraction and the Transport of the raw materials
• of the Transformation of the raw materials and the Manufacture of the product or during the preparation of the service
• of the Marketing of the product or the service
• of the Use or the implementation of the product or during the supply of the service
• of the Recycling of the product

Examples of assessment of gray energy

Metals are very greedy in gray energy, and the synthetic matters more than the natural matters.

The following materials were classified in the order at least greedy with greediest in gray energy:

• Concrete block: 0,7 MWh/m 3

• full Brick: 1,2 MWh/m 3
• Reinforced concrete: 1,85 MWh/m 3
• primary education Steel: 52 MWh/m 3
• Steel recycled: 24 MWh/m 3
• Copper 140 MWh/m 3
• Zinc - Titanium 180 MWh/m 3
• Aluminum 190 MWh/m 3

See too

• écobilan (or life cycle analyzes)

External bonds

• Which is what gray energy, by association Suisse ADER
• : definition on Ekopedia
• : Base ekoinventare on software Equer (downloadable version demonstration)
• ECO-BAT: Computational tool of the environmental impacts of the buildings