I'm in Quebec (Eastern Canada). Most of the electricity is produced from hydraulic power (dams) up north, while cities are in the southern part of the province. Most houses are electrically heated (especially those built after 1970). Production from water turbines is very efficient. Transmission losses are about 30%, because of the distance (> 1500km). Heating itself is 100% efficient, no moving parts, no maintenance. In this context, heating with a baseboard or CPU makes no difference.