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How much energy does it take (on average) to produce 1 kilogram of the following materials?

Wood, steel, aluminium, iron, glass, paper, plastics, copper, silicon, nickel, titanium, electronic grade silicon.

Image: Copper ore. Credit: S. Rae (CC BY-SA 2.0).

Image: Copper ore. Credit: S. Rae (CC BY-SA 2.0).

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How much energy does it take (on average) to produce 1 kilogram of the following materials?

  • Wood (from standing timber): 3-7MJ (830 to 1,950 watt-hours).

  • Steel (from recycled steel): 6-15MJ (1,665 to 4,170 watt-hours).

  • Aluminum (from 100 % recycled aluminum): 11.35-17MJ (3,150 to 4,750 watt-hours)

  • Iron (from iron ore): 20-25MJ (5,550 to 6,950 watt-hours)

  • Glass (from sand, etcetera): 18-35MJ (5,000 to 9,700 watt-hours)

  • Steel (from iron): 20-50MJ (5,550 to 13,900 watt-hours)

  • Paper (from standing timber): 25-50MJ (6,950 to 13,900 watt-hours)

  • Plastics (from crude oil): 62-108MJ (17,200 to 31,950 watt-hours)

  • Copper (from sulfide ore): 60-125MJ (16,600 to 34,700 watt-hours)

  • Aluminum (from a typical mix of 80% virgin and 20% recycled aluminum): 219 MJ (60,800 watt-hours)

  • Silicon (from silica): 230-235MJ (63,900 to 65,300 watt-hours)

  • Nickel (from ore concentrate): 230-270MJ (63,900 to 75,000 watt-hours)

  • Aluminum (from bauxite): 227-342MJ (63,000 to 95,000 watt-hours)

  • Titanium (from ore concentrate): 900-940MJ (250,000 to 261,000 watt-hours)

  • Electronic grade silicon (CVD process): 7,590-7,755MJ (2,108,700 to 2,154,900 watt-hours).

Note: 1 megajoule (MJ) = 277.77 watt-hour (Wh) Source: Environmentally benign manufacturing.

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Men you need to be a good mathematician to get that answer right

Random Person

Hey, an air table or embedded google sheet would provide a better view.


Hello everyone! Thanks for your article. I would ask if it is possible to have the energy consumption to produce 1 sqm of plywood. Would be perfect the follow details: birch fsc plywood 24 mm thick. Thanks


It has not been a trivial task for me to try to find these seemingly straightforward numbers! However I’d like to see the specific sources for the figures. At the moment the listed source is a website which links to over 70 papers. Would you have any time to be more specific with which papers were used for each figure?

I do love low tech magazine regardless, keep it up!

Cheers, Forty-two

Owen Thurgate

Amazing resource, really highlights the value of recycling aluminium and the high energy cost of plastic! Thank you!

kris de decker

@ forty-two

I made these calculations based on the data in those 70 papers…