U.S. Department of Energy - Energy Efficiency and Renewable Energy
Building Technologies Office
Better Buildings Alliance Distribution Transformer Specification
BBA has developed specifications for multiple technologies:
The Better Buildings Alliance (BBA) has released a specification for low-voltage, dry-type distribution transformers that outlines energy-related product requirements. Purchasers can utilize the specification today to ensure they are procuring a high-efficiency, high-quality product from manufacturers.
Distribution transformers built to the BBA specification can reduce energy losses by over 15%, compared to typical transformers, and if widely adopted could save U.S. businesses 3.2 TWh of energy, or about $310 million in energy costs, per year*. In addition, the BBA specification is unique in that it provides a no-load core loss recommendation. Transformer efficiency varies according to load. In instances where a transformer is oversized, it typically operates at sub-optimal efficiencies. This energy loss can be addressed through proper sizing, or by limiting the no-load core losses.
If you are interested in saving energy and saving on your business's utility bills consider using this specification when procuring a new distribution transformer.
* Assumes a 75kVA Dry-LVDT under constant loading at 35% of nameplate capacity for 8,760 hours at $0.098/kWh compared to proposed DOE standards. Actual savings depend on transformer capacity, the specific building load profile, and baseline transformer efficiency. Please consult the Energy Savings Calculator to determine the financial savings for your building.
How to Use the Specification
STEP 1: Answer the following set of questions to determine if a high efficiency distribution transformer is right for your building. If you answer "yes" to the first two questions and at least one other question, replacing your old transformer is likely to be a value-generating option for your building.
- Does your distribution transformer have input and output voltages less than or equal to 600 V?
- Do you own your facilities or are you responsible for the electrical system within?
- Are you constructing a new facility or performing major renovations that involve changes to the electrical system?
- Is your current distribution transformer more than 10 years old?
- Does your electrical demand profile change significantly throughout the day, week or year?
- Are your local electricity costs high, or are you concerned they will rise in the near future?
- Are you seeking an ENERGY STAR label or a green building certification?
STEP 2: Find financial incentives you may qualify for on the Database of State Incentives for Renewables & Efficiency website. Then calculate the financial savings you could achieve by switching to a high efficiency distribution transformer.
STEP 3: Download the BBA distribution transformer specification template, and develop a customized specification to reflect your specific site's needs.
STEP 4: Send your customized specification to one or more manufacturers to get quotes.
STEP 5: Purchase and install a high efficiency distribution transformer and start saving money and energy!
Below are links to additional resources as well as case studies demonstrating building energy savings and annual operating cost savings from buildings using highly efficient distribution transformers.
For any questions on this, or other, BBA specifications please contact BBA@ee.doe.gov.