Potential energy suppliers in IESO’s second long-term energy and capacity procurement said the ISO's auction rules favor natural gas generators by insulating them from most of the cost of gas transmission upgrades.

IESO will open some transmission projects to competition, although most will continue being awarded to incumbents.

IESO has 37.2 GW of installed capacity and 18,640 miles of transmission, both ranked seventh among the nine organized markets in the U.S. and Canada.