The water vapor cloud from the cooling towers at St. Paul Cogeneration’s wood-fired combined heat and power (CHP) plant on Kellogg Boulevard is a prominent feature on the Saint Paul skyline during the winter. This new facility burns wood chips in a highly-efficient CHP process to produce renewable energy in the form of electricity and heat for downtown Saint Paul building owners. Electricity from the plant is delivered to Xcel Energy. Heat from the plant is delivered to District Energy St. Paul’s district heating customers. Over 80 percent of the heating for downtown Saint Paul is from green energy produced at the plant using a renewable energy source—clean wood waste. The facility consumes 280,000 tons of wood waste each year, helping to eliminate a significant urban disposal problem.

What is the cloud?
The cloud is water vapor that is being evaporated to condense the steam which is used to create electricity. Cold + warm water = steam.

Why is the cloud so large?
The size of the cloud from the cooling towers is influenced by the outdoor temperature and humidity and the production level at the plant. The cloud is more prominent on colder days because the cold air condenses the water vapor from the cooling towers, creating the white cloud.

For more information, please contact Mike Burns at 651.297.8955.