Aiming to increase energy capture by 5% compared with existing blades, Denmark's LM Glasfiber is developing new basic airfoil profiles for both the outer half the blade, where most of the work is done, as well as the root area, where it is important to keep aerodynamic losses to a minimum. The development work includes optimisation of passive aerodynamic devices to improve performance. These take the form of small fins, or vortex generators -- often seen on the upper surface of aircraft wings -- that improve the aerodynamic efficiency, possibly by around 2%. The aim is to improve efficiency overall, from root section, tip section and the use of vortex generators, by 5%. The company's new wind tunnel is proving its worth, giving LM designers unlimited access to test facilities.