Energy has become increasingly important in international trade relations. However, the World Trade Organization (WTO) does not deal specifically with this sector, and this creates several problems when it comes to regulating trade in energy goods and services. The situation is further complicated, on the one hand, by the need to foster the diffusion of renewable energy to address the current environmental concerns and, on the other, by the total and overwhelming control exercised by the Organization of Petroleum Exporting Countries (OPEC) over the oil market. It is true that, recently, the WTO has shown an increasingly open approach towards environmental issues. However, free trade is still the backbone of the Organization and trade liberalization its main goal. This explains why the WTO Panel and Appellate Body are still reluctant to justify measures adopted to support the renewable energy sector that may conflict with international trade law. Different might be the case with fossil fuels, the main competitor of renewable energy. OPEC exploits several strategies to control oil prices, which, at least in theory, clash with international trade rules. However, whatever the reason, such practices have never been challenged in front of the WTO. The way WTO provisions are interpreted and applied by the Panel and the Appellate Body when environmental concerns are involved can be used as a starting point to forecast a hypothetical judgment in case OPEC's practices were eventually challenged.