Abstract
The goal of this paper is to determine why some Organization of Economic Cooperation and Development (OECD) countries allocate more public expenditure to research and development of renewable energy than others. This is attempted by offering a comparative analysis of the commitment to renewable energy by nineteen OECD governments from 1990-2000 using cross-sectional time series analysis. The main findings suggest that presidential democracies have higher levels of renewable energy R&D than parliamentary democracies and proportional legislative electoral systems have higher levels of renewable energy R&D than majoritarian electoral systems. However, these results should be interpreted cautiously as the impact of other political variables on renewable energy R&D, government composition and number of effective legislative parties, remains inconclusive.