The Canadian working group on expanding clean energy R&D collaboration is currently reviewing existing Canada-U.S. partnerships in order to identify prospective areas for long-term clean energy R&D collaborative initiatives as part of the framework mandated by the Clean Energy Dialogue Action Plan. The present scientometric study represents one of the sources this working group will draw on to develop a more robust understanding of the scientific production and collaborative landscape in the field of clean energy R&D and in three subfields of interest: future generation biofuels, clean energy vehicles and green buildings. This scientometric study found that the scientific output in clean energy R&D and its three subfields increased dramatically during the 2005–2009 period, internationally, in the U.S. and in Canada. Both these countries are among the 15 leading countries in clean energy R&D, with the U.S. being the largest producer in the field overall and in the three subfields. Indicators of scientific impact, quality and specialization suggest that the strengths of leading countries vary across the subfields, but overall in clean energy R&D, Sweden and Turkey stand out as having levels of impact and specialization that are above the world level. Canada, Germany, the Netherlands, the U.S. and the U.K. all rank above the world average in impact but are not particularly specialized in this field. Note that the small number of publications in green buildings research limited the conclusions that could be drawn from the data for this subfield.