Texas-based Stewart & Stevenson Power Products LLC, Atlantic Division has received an order for two MTU 16V4000 natural gas-fired gensets for a new 3 MW combined cooling, heat and power (CCHP) plant at a major trauma hospital in New York City.  

A technical power evaluation of the 448-bed facility was completed last year by New Jersey-based CHP developer Innovative Energy Strategies (IES) to determine the type of technology needed to provide additional reliable power and power quality enhancements to support an approved $70m hospital expansion.

In the wake of 2012’s Superstorm Sandy, many critical care facilities in the New York City metro area, and in particular on Staten Island, realized the need for increased power resiliency through an additional layer of energy security in the event of a grid outage. The chronic poor power quality before and after the storm event exposed many weaknesses in the hospital’s power architecture which was severely impacting the performance of critical and sensitive diagnostic equipment.

The proposed installation of two MTU 1534 kW continuous rated gas genset modules based on an N+1 redundant configuration was chosen based on cost per kW, electrical and thermal efficiency, critical uptime, ability to operate on low pressure natural gas (2.6-3.6 psi), guarantee of operation at one-half g of NOx per bhp/hour, performance under site ambient conditions, system controls capability and low cost of O&M. All of this provided the most competitive total cost of ownership over the expected plant lifetime.

The CCHP system will provide 1534 kW at 4160V all year long, and the two generators will be operated in a lead/lag sequence of operation so the availability of a single generator at any point in time will approach 100 per cent. A total installed capacity of 3068 kW will be available to support peak hospital loads, giving the hospital the ability to operate in a grid-isolated mode for extended periods of time.

The exhaust gas from the engines will supply two heat recovery steam generators (HRSGs) to augment the hospital’s steam demand while the jacket water will be utilized to supply two 750-tonne dual stage absorption chillers. The electrical power will re-feed the hospital campus electrical distribution system and will provide microgrid islanded operation if utility power is lost.

Stewart & Stevenson partnered with IES to provide a detailed technical specification in order to secure significant New York state funding grants that will significantly offset the cost of installation. The estimated annual operational savings to the hospital of $1,600,000 secured the investment and facilitated the financing of not only the entire CCHP project, but also the reorganization of the electrical delivery system of this 114-year-old facility.

Stewart & Stevenson Power Products LLC-Atlantic Division is the authorized distributor for MTU Onsite Energy, and a New York State Energy & Research Development (NYSERDA)-approved vendor of pre-engineered CHP systems.

Arthur LaBarbera is Director, Gas Power Systems Northeast at Stewart & Stevenson Power Products LLC