Published August 2006 by the Renewable Energy Foundation

Wind turbines do not emit CO₂ at the point of generation but, in common with all generation modes, emit it during construction and, through damage to the site, over a much longer period.

The carbon debt varies widely from site to site and comprises emissions arising from fabrication, from construction (including transportation), from the indirect loss of fixation by plants lost to construction and, lastly, from the long-term release of CO₂ from carbon stored in peat as it dries out after construction.

Peat is a major carbon sink due to dead plant remains accumulated over millennia and held in perpetuity because the bog’s wet, acid conditions prevent the access of oxygen and inhibit the bacteria which would otherwise rot the vegetation.

Draining peat for construction reverses these long-term processes: the soil is exposed to the air, the carbon is converted to CO₂ and released slowly to atmosphere.

This paper was possibly the first to take all these factors into account in drawing up a carbon audit for wind power. SWAP collaborated with Dr Hall in producing a model for quickly calculating the effect of a range of hitherto unconsidered parameters on any site using information provided in its Environmental Impact Assessment. It also assisted with the above guide to using the model. (The model is in the form of a spreadsheet. Copies are available on application.)

► Back