A proven and cost-effective method of recovering energy for a district or local heating grid is achieved by condensing the water in flue gases. The amount of energy recovered depends on the district heating water temperature, and can be improved by using a heat pump, which can increase recovery by approximately 5 percent.
Watch this short time-lapse video of B&W delivering a new flue gas condensation system to a waste-to-energy plant outside Copenhagen that delivers approximately 30 MW of energy to the district heating network. By cooling the flue gas to below its dew point, it is possible to recover large quantities of latent heat.