Carbon Confusion January 16, 2009

At the risk of resuscitating the age-old carbon emissions factor discussion already exhaustively debated by the whole industry, the news that the Advertising Standards Authority is requiring turbine suppliers to use the 0.43 kgCO₂/kWh for avoided emissions has just muddled things up a bit more.

At least for design teams, the figure used to be constant throughout the project stages, but now the pre-planning process for renewables projects may be using this lower figure. When that project is building-related, architects may start by using the 0.43 figure they get from the suppliers, then 0.422 for grid-supplied and 0.568 for grid-displaced electricity for planning submissions, Part L and Code, 0.55 for the Display Energy Certificate if the building is public, and finally 0.523 when the building owner is calculating its ISO 14064 emissions, per DEFRA guidance. That’s five different emission factors for the same project!

Granted, some of these figures aim at measuring emissions during different timeframes for different purposes, but, without getting into the merit of which figure is the right one, a bit of consistency from the various government agencies wouldn’t hurt…