DOE's Germantown acility Upgrades to Energy-Efficient Distribution Transformers

August 1, 2002

Operating 24 hours a day, 7 days per week, distribution transformers tend to be a building's "behind the scenes" electrical energy hog. Transformers provide electrical power (at the proper voltage) for all other electrical equipment and plug-in devices found in a building including lighting, office computers and peripherals, air conditioning, appliances, vending machines, and a wide range of specialized equipment. Transformers have no moving parts and typically last 35 years or more, rarely requiring any attention or maintenance. However, their performance does deteriorate with time so they eventually need to be replaced, as was recently the case at DOE's facility in Germantown, Maryland.

The original DOE Germantown building, completed in 1958, provides office space for approximately 2,000 DOE personnel. The facility includes a large auditorium, a cafeteria, and a computer center. DOE, the facility tenant, and the General Services Administration (GSA), the owner, have been upgrading the facility to improve operating conditions and energy efficiency. The original distribution transformers in the building were nearing the end of their useful lives so GSA initiated a project in the late-1990s to replace the facility's aging transformers. A total of 53 transformers were identified for replacement, at a cost of $360,000.

Following a suggestion from FEMP, DOE's Mike Shincovich, an engineer with the Engineering and Facilities Division, recognized transformer replacement as a possible energy-saving opportunity. Shincovich's preliminary analysis revealed that more efficient transformers would reduce DOE's electricity costs and would readily meet the Federal government's life-cycle cost effectiveness criteria set forth in Executive Order 13123 and CFR 48 Part 23. He requested that GSA specify high-efficiency units in the project's request for proposals. Shincovich requested that the efficiency levels for the distribution transformers meet those set forth in FEMP's series of product-efficiency recommendations, which provide efficiency criteria for products in the top 25th percentile of efficiency and/or ENERGY STAR® compliant products. These efficiency recommendations are based on the National Electrical Manufacturers Association Standard TP-1-1996 Guide for Determining Energy Efficiency for Distribution Transformers. This recommendation, along with FEMP's 40 other recommendations, can be downloaded from FEMP's Buying Energy Efficient Products web site.

Because TP-1-compliant transformers cost more than standard efficiency transformers, DOE contributed an additional $57,000 to GSA's base project funding of $360,000. The transformers were installed in spring 2001. Prior to this, DOE, in cooperation with the Environmental Protection Agency, studied the load profiles to quantify expected energy and cost savings for a set of the transformers being replaced at the facility.

The study estimated that DOE would save $10,000 annually in electricity costs if the models installed complied with FEMP's efficiency recommendations instead of standard efficiency levels. For the Germantown facility, GSA and DOE chose Cutler-Hammer's TP-1 models that met FEMP's criteria. Payback for the transformer project was 5.7 years at an electricity cost of $.062 per kilowatthour. Given that the life of a transformer is roughly 30 to 40 years, the annual savings will offset the higher initial costs of the more efficient transformers.

When transformers are due for replacement, energy-efficient models generally have payback periods well within Federal guidelines. However, when transformers still have a significant amount of useful life, these savings are not usually sufficient to justify early replacement. Nonetheless, with systematic replacement of aging transformers, the Federal government could save approximately 420 gigawatthours in annual energy consumption and $25 million in annual energy costs. Through its Federal procurement program and its efforts to incorporate energy-efficiency levels into construction guide specifications, FEMP's goal to help save Federal tax dollars and move the Federal government towards greater efficiency can be achieved.

For more information on the DOE Germantown facility project or FEMP's product efficiency recommendations, please contact Alison Thomas of FEMP at 202-586-2099 or