This academic approach has meant that the energy use of complex operations has been accurately mapped.
Rarer still – if at all – do companies report the energy use of homeworkers.
"Even if you know the energy use of your building, you don't have any context," she said.
"Ideally, the energy use of a building can become a factor in the decision-making process," Ms. Holzner said.
This US Department of Energy webpage has a handy formula for estimating the energy use of various household appliances, including the iron.
Last month, Google announced that it had signed a contract to purchase enough local wind energy to offset the energy use of the company's entire headquarters.
The energy use of the Palm mill is one of the highest across our supply base, even though it is one of the newest mills in Europe.
With over 1.5 billion people online around the world, scientists estimate that the energy use of the internet is growing by more than 10% each year.
The 95 Eiggers cut the energy use of their homes and businesses by 47% by improving home energy efficiency and - quite simply - learning to use less energy.
His system is designed not for the relatively high energy use of a typical American home, but for homes with much more modest needs.
And in offices, a one-degree increase in the temperature can cut the energy use of air conditioners by 3-4%.
