On January 1, 1996, CFCs will be virtually phased out of production. While this presents certain challenges to managers of refrigeration and air conditioning equipment, it also provides an ideal opportunity to upgrade equipment and increase the energy efficiency of buildings. Aside from substantial lifetime energy and dollar savings, chiller plant upgrades will improve occupant comfort, system reliability, and operation and maintenance.
The Energy Star Buildings program is a voluntary, profit-based program that strives to reduce energy costs and energy-related pollution in participating buildings. The program strategy involves a series of building upgrades to reduce total energy loads while maximizing savings at the lowest initial cost. Load-reducing efficiency upgrades in the early stages of the program allow for chiller downsizing at the end. Installing a more efficient and smaller chiller lowers the initial cost and increases annual energy savings. The overall goal of the program is to reduce a facility's energy consumption by 25-50% with investments yielding an internal rate of return (IRR) of 20% or more. Green Lights Partners can join the program by signing an addendum to the Green Lights agreement. For more information, call or fax the EPA at the numbers listed below.
The chart below show the energy consumption (kWh/ft2) in typical office buildings (3, 7 & 20 floors) for four CFC-chiller conversion options.
Chiller upgrades have been successfully implemented in Energy Star Showcase Buildings. Each case used load reducing measures to allow for chiller downsizing and a smooth transition to non-CFC refrigerants. Two such examples are J.C. Penney in Cumberland, GA and Resource Conservation Center in Washington, DC.
A 160,000 sq. ft. J.C. Penney retail store located in Cumberland, GA, used 280-ton twin centrifugal chillers for cooling. The chillers contained R-11, a CFC refrigerant that will be phased out at the end of the year. After reducing the cooling load by completing stages 1 through 4 of the Energy Star Buildings strategy, J.C. Penney was able to downsize to a sign 250-ton gas-engine chiller using R-22, with variable speed drives and energy-efficient motors on the pumps. They also qualified for a $35,000 rebate on the chiller from Atlanta Gas LightCompany.
ESB Program Savings:
Initial Investment: $384,000
Annual Savings: 723,600 kWh (25%)
$66,500 per year.
RCC is a 244,000 sq. ft. facility consisting of two office buildings in Washington, D.C. A single cooling plant services both buildings and consists of a 388-ton main chiller and a 280-ton backup chiller. After reducing the cooling load by implementing stages 1 through 4 of the Energy Star Buildings strategy, RCC replaced the 280-ton chiller with a 260-ton screw chiller using R-222, which became the main chiller. In addition, energy-efficient motors and variable speed drives were installed. RCC also qualified for a $95,000 rebate on the chiller from PEPCO.
ESB Program Savings:
Initial Investment: $422,000
Annual Savings: 1,141,400 kWh (30%)
$96,150 per year
The installed cost of an energy-efficient chiller increases with improved efficiency yet decreases with reduced capacity. The chart below shows estimated costs versus capacity for a new chiller rated at .55 kW/ton and one rated at .60 kW/ton. As is shown in the case studies, utilities often provide financial incentives for installing energy-efficient chillers. In addition, contact your state energy office about grants to public sector facilities that initiate energy-saving measures.
