100 Percent LED Cambridge

Poster for 100% LED campaign, saying Go 100 Percent LED to save money and be part of a 100 percent LED Cambridge

Saving energy through home lighting has never been easier! LEDs use six times less energy than older lights, making them an easy way to save money and energy, and free of mercury. To save energy in your home, you can take advantage of Mass Save discounts and Cambridge's upcoming bulb swap events.

Free LED Bulb Swaps This Spring

The Cambridge Energy Alliance will host four events this spring where residents can exchange up to three incandescent or CFL lightbulbs for LED lightbulbs. The swaps are free and open to all Cambridge residents at the following events:

  • Cambridge Winter Farmers Market, Saturday, March 17, Cambridge Community Center Gymnasium, 5 Callendar St., 10:00a.m. – 1:00p.m.
  • Cambridge Science Festival, Friday, April 20, Cambridge City Hall, 795 Massachusetts Ave. 12:00p.m. – 3:00p.m.
  • Cambridge Public Library, Main Branch, Saturday, May 19, 449 Broadway, Beech Room (to left of entrance), 12:00p.m. – 2:00p.m.
  • Cambridge River Festival, Saturday, June 2, Lechmere Canal Park, 11:00am – 6:00pm
  • Central Square Soccer Night, Wednesday, June 27, Sennott Park, Broadway and Prospect St., 6:00-8:00pm (in partnership with Mothers Out Front)

The events will offer standard A19 LEDs, which fit most lamps and fixtures, and BR30 LEDs, typically used for recessed lighting. Exchanges are limited to 3 bulbs per household to ensure supply for all participants.

Discounts on LEDs

As part of the 100% LED campaign, we held an limited-time online promotion, a pop-up store, and a free bulb swap, helping Cambridge residents swap out thousands of bulbs in the process. While these promotions have wrapped up, you can still get discounts on LEDs (thanks to MassSave) at your local hardware store. You can also buy low-cost LEDs online at the MassSave store.

Selecting the Right Bulb: A Quick Guide

  1. Choose your bulb shape: The standard bulb for most lamps and fixtures is an “A19” bulb. Other common shapes in Cambridge homes include globe (G) and recessed ceiling lights (BR, R, or PAR).
  2. Choose your base: The standard base is a medium screw base. Chandeliers and smaller lamps may use a noticeably smaller, 'candle' base.
  3. Choose your brightness: Incandescent lights are measured in Watts, the power used by a light, but LEDs are measured in Lumens – the total amount of visible light emitted.
    • 60 W bulbs can be replaced with an LED of approximately 800 Lumens
    • 40 W bulbs can be swapped for an LED of around 450 Lumens
    • For other brightness levels, see this chart from MassSave; for halogens and floods, check the packaging or manufacturer's website to get information on the brightness.
  4. Choose your temperature: Light temperature (or color) is measured in Kelvin (K) along a spectrum. The lower the number, the warmer the light; the higher the number, the cooler the light. Though preferences are subjective, here is a quick reference guide:
Name of White: Similar To: Often Used In: Kelvin Color Temp: Additional Info:
Warm White
A typical incandescent bulb Living and dining areas 2700-3500K Softens the environment and creates relaxed feeling
Natural White
A typical retail space with fluorescent lights Kitchens, bathrooms 3500-4500K Cooler lighting is better for places where tasks occur
Daylight White A typical noon sun; often used for high color definitions Retail spaces, offices, and for reading 4500-6000K Older eyes are eased by cooler temps, particularly when reading

For Dimmable Lights

If you would like a bulb that can be dimmed, look for “dimmable” in the product name. Note that, if you want your LEDs to also appear warmer as they are dimmed (as incandescents do), make sure the bulb has a “warm dimming” label. In rare cases, when switching dimmed lights to LEDs, you may need to change your dimmer switches, with the help of a qualified electrician.

For More Information

For questions, please email us at eadvisor@cambridgeenergyalliance.org.