An increasing number of researchers stress the importance of national planning institutions׳ role with respect to promoting an “effective” decision-making process in terms of bringing about sustainable energy. Impact Assessment (IA) procedures are seen as having strong potential in supporting environmentally conscious energy production. This article discusses criteria for sustainable wind power planning and compares the centralised planning systems for wind energy in two countries – Norway and Scotland – as illustrating cases. We ask the following: What key criteria should be present to secure sustainable wind energy planning, and what are the critical institutional conditions to fulfil these criteria? A review of relevant IA literature reveals four key criteria for promoting sustainable wind planning: (i) clear and integrated political priorities, (ii) stakeholder involvement, (iii) strategic environmental assessment (SEA) and (iv) stringent permission and assessment requirements. We also determined that critical institutional conditions exist that effectively promote sustainable energy production: (a) coordinated energy policy institutions, (b) legitimate planning procedures, (c) that SEAs are followed in the decision-making process and (d) statutory planning regulations.