DENVER — When a massive event center was being developed in Denver, planners had to contend with two existing 6-foot-wide sewer pipes that emptied into the river, creating an unsightly dilemma.

Denver is testing whether sewer heat, geothermal wells and district thermal infrastructure can retrofit dense downtowns without requiring major electrical-system expansion.

Consistent performance, easy installation and simple climate control—Electric radiant heat warms the home from the floor up. New England mornings can tempt some of the toughest to roll over, turn off ...

When a massive event center was being developed in Denver, planners had to contend with two existing 6-foot (1.8 meters) wide sewer pipes that emptied into the river, creating an unsightly dilemma.