Payback Calculator

Have you ever wondered if that new gadget or new light bulb is worth the cost? Today we are announcing the Power Payback Calculator to allow you to quickly determine how long it will take to recover money spent on a new product or upgrade to save power.

To put this into context, the simple example is changing a light bulb. Today you may have a 40 watt incandescent light bulb in your closet, and you are considering a pricey $15 LED light bulb that only uses 2.5 watts. You figure that the closet light is on for 30 minutes a day – how long will it take for the energy savings to offset the $15 spent?

In my case (12.5 cents per KwH), it would take around 17.5 years for that LED light bulb to pay off – probably not the best financial decision. Now, if you had been replacing a 60 watt bulb that ran for 2 hours per day, you’d be looking at a payback in under 3 years. And if your power cost is very high, such as in Hawaii or New York City, your payback may be under 2 years.

I like to use this tool for those exact scenarios. It helps you determine if a project makes sense for you, and it also helps give you an idea of how long a product may need to last before it pays for itself. 4.5 years for an LED bulb should be likely, for example. I’ve also used this for determining if a Smart Strip makes sense in a particular application.

Introducing the Power Savings Calculator

I've created a new tool to allow anyone to quickly determine how much money a planned purchase or behavioral change may save.

Have you ever wondered just how much leaving the light on all night costs you?  Or how much money you'll really save if you replace a lightbulb with a compact fluorescent (CFL) bulb?  Perhaps you are contemplating buying a Smart Strip and wonder if the amount of power it saves will be worthwhile?

In any of those cases, simply use the power savings calculator to find out.  All you need to know is how much power you will be saving (in watts), how many hours per day you will be saving that power, and what your electricity rate is (in the US, typically between 9 and 13 cents).

Use the Power Savings Calculator to calculate your money saved based on the amount of power you've saved.

1. Enter your local power price in cents.  This is typically measured in cents per KwH (kilowatt-hour).  Typical prices range from 9 to 13 cents.
2. Determine how many watts of power were saved.  For example, if you replace a 60 watt light bulb with a 12 watt CFL, you will have saved 48 w.
3. Enter how many hours per day you are saving that power.  For example, if that light runs for 4 hours per day, you'd enter 4 hours per day.

INPUT DATA
Cost Per KwH	cents
Watts Saved
Hours Used Per Day
RESULTS
Daily Savings	dollars
Monthly Savings	dollars
Yearly Savings	dollars

You may be wondering how to determine how much power is being saved. the lightbulb example above is easy, but how do you calculate 'vampire power' that electronics draw even when supposedly off? For that, you may need a Kill A Watt or some other power measuring device. I like the Kill-a-watt because of its easy of use.

Using the kill-a-watt, I determined that my stereo/TV center was using about 22 watts of power that I was able to reduce using the Smart Strip mentioned above. That saves me about $16 per year, and the beauty of the smart strip is that unlike regular power strips, the smart strip allows you to keep critical components powered on all the time. For example, if you have Direct TV and ever power off your DVR, you know it can take 5 minutes or more for it to boot up and re-sync with the satellites. The smart strip allows you to power off everything else, but leave that DVR connected.