Central Plant Design

The performance of a central utility plant in a healthcare facility is critical to the delivery of safe patient care. There are many important aspects to consider when replacing equipment, upgrading components, or building a new central utility plant. An unplanned outage or equipment failure can result in the loss of ability to treat patients which can have significant safety and cost ramifications. Sound central plant design and planning is the first step in creating a reliable, economical, and maintainable system.

Designing for the Future

When designing a new central utility plant, or significantly expanding an existing plant, future expansions may not seem like a priority. However, making provisions now is going to make your future expansion projects easier and more economical.

  • The first step is to assess possible future buildings, additions, and other mechanical, electrical, and plumbing (MEP) loads. Coordinating a MEP master plan with an overall facility master plan is an efficient means of assessment.
  • Space should be designated within the building or for a building expansion to accommodate future central equipment. A good layout should also consider ingress paths of future equipment and cost effective egress paths for old equipment.
  • Strategic sizing of equipment today could help meet regulatory redundancy requirements in your current plant as well as your future projects.

Interrelation of Services

A central utility plant includes multiple services that rely on each other. A redundant boiler may not be available when you need it if the emergency generator was not sized to accommodate the load or a control panel was not connected to emergency power.

  • Each critical component of a system should be evaluated for its emergency power requirements.
  • Central fuel oil tank sizing should be coordinated with required boiler runtime as well as emergency generator operation requirements in accordance with the facility’s emergency preparedness plans.

Operation & Maintenance Considerations

Coordination of space for equipment and utilities during design occurs once, but working within inadequate service clearances can be a long term problem.

  • Central plants should be designed with adequate horizontal and vertical clearances for lifting centrifugal compressors, cleaning or replacing boiler and chiller tubes, and working safely around electrical equipment.
  • Uninterruptible services are paramount in healthcare settings. Multiple boilers and chillers should be connected to headers with adequate isolation valves. Consideration should be given to items such as duplex fuel oil filters that can be switched over during operation.
  • Emergency connections to domestic water systems, boiler systems, and chiller systems are recommended. A relatively small investment in these temporary connections can make future equipment replacements much easier.

Energy Diversity & Efficiency

Both new and existing central plants can be evaluated for source energy diversity and efficiency improvements.

  • Waterside economizers are commonly used to provide chilled water capacity in winter months and typically prove to have short payback periods in healthcare facilities.
  • Most hospitals utilize boilers that can take advantage of flue stack economizers or blowdown heat exchangers to recover energy that is literally going out the roof or down the drain.
  • Prime mover generators can be evaluated for demand limiting and cogeneration of electricity and hot water.
  • Code and industry standards for energy conservation are continually being updated. Existing facilities should be regularly evaluated for opportunities to increase energy savings and reduce operational costs.

Central utility plants are the workhorses of healthcare facility MEP systems. Their design requires a coordinated effort from design engineers, maintenance staff, and facility decision makers. If you need assistance in understanding more about your existing campus infrastructure or have questions for your next project, please do not hesitate to contact Jon Slagel, PE at (717) 845-7654 or jbs@ba-inc.com.

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