Chilled Water Optimization, LED Upgrades Save Big at Big Pharma

By Tom Pagliuco, Executive Director, Global Energy Engineering, Allergan

There are currently two types of projects that typically have attractive economics for pharmaceutical facilities and we have been focusing our attention on: LED lighting upgrades and chilled water optimization projects.

Lighting is a low risk, easy to implement energy savings opportunity. There are typically good incentives/rebates for LED upgrades which make the economics work even in locations with low electric rates. LED upgrades projects have become a standard across our global facility portfolio. If a site doesn’t have an LED upgrade in their energy reduction plan, then management has started to ask the question, “Why aren’t you doing an LED upgrade?”

Chilled water optimization is a large percentage of a pharmaceutical facility’s energy usage, so it is an obvious area to focus on, especially if the facility is in a hot, humid environment. Finding projects that can be replicated at multiple facilities can also apply a little “peer pressure” to the plants that are slow to implement. I have branded the chilled water optimization project to make it easy to market and get sites to understand the technology and savings potential. We are calling it Project CHIL-E (Chiller & Hydronic Improved Lifecycle Efficiency).

Project CHIL-E (Chiller & Hydronic Improved Lifecycle Efficiency) – a holistic approach

HVAC represents approximately 65% of a pharmaceutical facility’s total energy usage and the chilled water generation and distribution system is a prime area of focus when looking for energy and GHG emissions reductions. Most chilled water systems are operated as traditional constant primary loop, variable secondary loop hydronic systems. Low operating delta T is a common symptom of most chilled water distribution systems, resulting in over pumping water in the primary and secondary loops, decreased chiller efficiencies and a (perceived) lack of chilled water capacity.

This project was completed at our largest site and energy user. The site is an R&D campus consisting of laboratory, office and commercial manufacturing space. Chilled water generation consists of 5 VFD controlled, water cooled centrifugal chillers with a total installed capacity of 6,300 tons. The system is operated as a constant primary, variable secondary system; VFDs are installed on most of the condenser, primary and secondary pumps and cooling tower fans. The chilled water loop is well designed and operated but low delta T was a sign that the system was a candidate for optimization. Project CHIL-E uses advanced process control (APC) technology to control the operation of the chilled water plant and optimize the total system energy efficiency (measured in kilowatts per ton of refrigeration). The control and energy optimization system architecture is based on the integration of the APC system into the existing BMS.

Annual energy usage and cost savings are forecasted at >4,700 MWh and $542,000. This project will reduce the site’s total electric power usage by just under 10%. Additionally, the local utility provides rebates for chilled water optimization projects that are estimated to reduce the cost of the project by $250,000, yielding a simple payback for the project of just over 6 months. The project was validated using a rigorous M&V protocol as required and administered by the utility.

Project CHIL-E has been adopted as a best practice methodology to optimize chilled water systems and will serve as a template for other sites in our facility portfolio to follow. Similar chilled water optimization projects are in development for at several other Allergan plants.