New York City steam system
The New York City steam system is a district heating system which takes steam produced by steam generating stations and carries it under the streets of Manhattan to heat and cool high rise buildings and businesses. Some New York businesses and facilities also use the steam for cleaning and disinfection.
The New York Steam Company began providing service in lower Manhattan on March 3, 1882. Today, Consolidated Edison operates the largest commercial steam system in the world. The organization within Con Edison that is responsible for the system's operation is known as Steam Operations, providing steam service to over 1,700 customers and serving commercial and residential establishments in Manhattan from Battery Park to 96th Street uptown on the West side and 89th Street on the East side of Manhattan. Roughly 24 billion pounds (11,000,000 t) of steam flow through the system every year.
Steam for heating is inherently fuel efficient; boiler efficiencies approach 90%. Approximately 30% of the ConEd steam system’s installed capacity and 50% of the annual steam generated comes from cogeneration.Cogeneration and Heat Recovery Steam Generation (HRSG) significantly increase the fuel efficiency of cogenerated electricity and thereby reduces the emission of pollutants, such as NOx, sulfur dioxide, carbon dioxide, and particulate matter, and reduce the city's carbon footprint. Con Edison is promoting the use of steam for cooling in the summer months, something that can be accomplished with the installation of absorption chillers. Such trigeneration systems result in additional energy and pollution savings, while reducing peak electrical loads.
Clouds of condensation can sometimes be seen rising from manholes in Manhattan through orange and white "chimneys". This can be caused by external water being boiled by contact with the steam pipes or by leaks in the steam system itself.
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