From other forum (originally Kim Talus, OGELFORUM) I noticed interesting ongoing WTO case (WTO DISPUTE SETTLEMENT: DISPUTE DS412).
In this case Japan claimed that the measures are inconsistent with Canada’s obligations under Article III:4 and III:5 of the GATT 1994 because they appear to be laws, regulations or requirements affecting the internal sale, offering for sale, purchase, transportation, distribution, or use of equipment for renewable energy generation facilities that accord less favorable treatment to imported equipment than that accorded to like products originating in Ontario.
Interesting case in many ways. In brief e.g.: electricity as good/WTO and XX-article. Accoring to WTO web-pages the panel expects to complete its work by the end of November 2012.