Scotland's government is planning to build large-scale wind farms to reduce carbon emissions from electricity production, some of which could be situated on peatlands. We contend that wind farms on peatlands will probably not reduce emissions, unlike those on mineral soils.

Wind farms are often located in upland areas because most of these are windy, distant from residential areas and of low agricultural value. Peatlands are prevalent in UK uplands and are richer in carbon than mineral soils because peats are formed from decomposing wet vegetable matter. Peatlands therefore have a higher net carbon loss when drained for construction.

The UK wind industry uses a method we and our colleagues developed to estimate carbon emissions (D. R. Nayak et al. Mires Peat 4, 9; 2010). On this basis, and assuming current emission factors for electricity generation, our previous work argued that most peatland sites could save on net emissions if peat is not drained and if sites are restored after construction.

However, emissions factors are likely to drop significantly in the future owing to reduced fossil-fuel use in electricity generation (see go.nature.com/lnowou). As a result, peatland sites would be less likely to generate a reduction in carbon emissions, even with careful management. Unless the volume of peat excavated can be significantly reduced relative to energy output, we suggest that construction of wind farms on non-degraded peats should always be avoided.