Over the past few months I’ve been changing over the most frequently used lights in my house with new energy efficient LED light bulbs.  Many of the new bulbs have highly accurate color temperatures (important for consistent lighting over time…especially when illuminating photographs!) and have dramatically come down in price over the past few months.

Before I started this conversion process, I ran some lighting OpEx calculations to see how long it would take me to recover the higher cost of the LED lights.  To my surprise, and thanks to my higher California cost of electricity, these new bulbs don’t take very long to pay for themselves. I recently shared the Excel spreadsheet I create to calculate the OpEx savings with a photographer who is opening up a gallery and invested in LED lights.  I figured if he found it valuable others might as well, so I’m sharing it publicly here.

To use the calculator:

1. Download the Lighting Opex Calc document
2. Change the Average cost per Kilowatt Hour (yellow field) to your cost for electricity (industry calculations typically use $.11/KWH, I suspect most people’s are slightly higher like mine)
3. Update the rows for each similar wattage light on each room’s switch (add more rows and fill down the OpEx Costs fields as needed)
4. See how many Months/Years it will take to break even on the cost of the new light bulbs.

If you find this calculator valuable, drop me a line and let me know.

Some leasons learned to date:

• Try LED bulbs purchased locally from stores with good return policies; when paying $30-$60 per bulb, you want to make sure it is exactly what you need now and for the next 10+ years, if it’s not perfect, take it back. These bulbs cost too much for them not to be exactly what you want. LED bulb manufacturers should also learn to package their bulbs in resealable packages for this specific reason…
• I’ve had good luck with bulbs from Home Depot and Lowes…
• If you have dimmer switches, your LED bulbs will be brighter than you expect at the lowest setting, something you have to get used to. And I’ve heard rumors of dimmer switches with more than 4-5 bulbs sometimes having problems where the bulbs flicker.
• If you have digital dimmers designed for halogen lights (to not produce a hum), they won’t work with LED bulbs.