Steinway's Solar-Driven System for Industrial Dehumidification and Steam Generation
Over the past several years, Steinway & Sons has been aggressively addressing productivity and energy issues at their 150-year-old manufacturing facility in New York City. As part of this effort, ERS worked with Steinway to install rooftop tracking parabolic trough solar collectors in conjunction with a dual-fuel (solar input or natural gas) absorption chiller for cooling/dehumidification and a steam generator for process heating purposes. To date, this project is the largest solar-sourced industrial heating/cooling system in the world. In the summer months, this solar fluid drives a 100-ton double-effect absorption chiller enabling humidity management in the Action Department where the intricate keyboard mechanism of the piano is manufactured. If dehumidification is not needed and the collectors can generate hot water above 275°F, a steam generator is used to develop 15-psig steam to offset a portion of the plant's continuous steam load. Simultaneous dehumidification and steam generation is also supported by this system. The system became operational and was partially commissioned in the late summer/fall of 2010 and will be fully commissioned during the early cooling season of 2011.
Thirty-eight Abengoa Model PT-1 solar collectors mounted on the roof concentrate heat onto evacuated glass tubes, heating a pressurized (115 psig) water and glycol mixture from nominally
320°F to 340°F. The actual temperature varies with solar availability but is limited to 350°F maximum.When cooling is needed, the diverting valve directs this hot water to a 100-ton double-effect absorption chiller. The dual-fuel chiller uses natural gas when cooling is needed and solar is not available. It can run entirely on gas or use gas to supplement solar-sourced energy. When dehumidification is not needed and the collectors can generate hot water above 275°F, the hot water circulates through a vertical helical tube and shell steam generator heat exchanger and produces 15 psig process steam to offset a portion of the plant's constant 1,200 kBtu/h load. Key components of the system can be seen in the figure on the left.
The system, which was partially funded by the New York State Energy Research & Development Authority (NYSERDA), became operable late in the cooling season of 2010 and data is now being captured to evaluate its full performance. The project recently won “Renewable Project of the Year” for the region from the Association of Energy Engineers.
For more project details, see Mark D'Antonio's 2011 ACEEE paper Post-Installation Performance Characteristics of a Solar-Driven System for Industrial Dehumidification and Steam Generation.