Tuesday, June 3, 2008


Since we moved to Hilo, Hawaii the high cost of our monthly electric bill has made us curious about how much electricity each appliance and device in our home is actually using. We wanted a gadget that we could plug our appliances into and view how much electricity it was actually using to identify the worst offenders.

We finally found a gadget called the Kill A Watt Electric Usage Monitor and ordered it online from Northern Tool & Equipment (northerntool.com)

Once we received the gadget we began plugging our various appliances, computers, and devices into it to see how much electricity they were using. We discovered appliances were using power even when not in use, just by being plugged in, like our coffee maker, exercise bike, and hand held vacuum cleaner. These devices draw power 24 hours a day as opposed to a light bulb which only draws power when it is turned on. We discovered that a fan speed setting at high drew almost double the power of a fan speed setting on low. Air Conditioners, on the other hand had a minimal difference due to the setting and the power draw of a small window AC is 28 times the power required for a ceiling fan.

I was telling someone from Puna about my findings and he laughed and said he had discovered that over 25 years ago when he installed his solar system. It is called a “ghost load” and is a top challenge for solar systems as it drains the power off the system without any benefit. He keeps all his appliances unplugged to reduce his power load.

The gadget has given us the ability to understand and control our power usage.

Here is our personal Electricity Conservation progress report based on our HELCO power bill:
In Feb 2008 – our average use per day was 28KW translating to $10.77/day

- We replaced our 60 watt light bulbs with 26 watt bulbs
In March – our average use per day was 21.4KW/day translating to $8.33/day

- We turned off appliances when not in use based on the Kil-a-watt gadget readings
In April – our average use per day was 17.7KW/day translating to $6.46/day

We have reduced our daily Kilowatt usage by 42%, which is a good start. We will continue to find ways to reduce our usage as the cost per KWH continues to rise each month.


Anonymous said...

Aloha, I too am an unrepetent energy hawk. I am sure I am a total pain in da okole to hubby.
I have lots of ways to save the kwh/day in Puna. I have reduced my bill to a mere $3.54 a day. Thats running two home biz' and two young pubescent boys. There are lots of ways to keep kalas for thou instead of almighty HELCO.

Anonymous said...

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