Despite being wound down, the Iraq war is also set to cost US taxpayers $51 billion (£32 billion) in 2011, while upwards of $1 billion (£620 million) has been spent by the US on the intervention in Libya. Brig. Gen. Anderson claims billions of dollars could be saved if the US military used simple energy-efficient techniques, such as spraying tents with common insulation foam used in domestic roofs.