This report examines the feasibility of private investment in wind power in Colombia within the current regulatory framework. It focuses especially on the regulatory methodology for estimating the ‘firm energy’ that wind power plants are capable of providing in Colombia to back up hydro generation during extended periods of drought (El Niño weather events). The report concludes that the current methodology probably underestimates wind’s firm energy contribution by a substantial amount. This in turn means that wind power stations receive a lower firm energy payment than they should. The authors argue that this could be an important barrier to investment in wind power in Colombia and recommend that the Colombian government reconsiders its methodology for estimating the firm energy capacity of wind power and of other (non hydro) sources of renewable power.