Washing in a comfortable temperature for at least 25 seconds. Is more than enough.   I usually sing Twinkle Twinkle Little Star to time myself.

This can be a considerable savings as there is less hot water used and even less water as you’re not stuck waiting for the water to heat up.

We need to take individual responsibility and if we each do the little things they will add up.  Walking and biking,  changing light bulbs,  insulating, and turning down the thermostat not only help your bills but also the alleged impact of your existence on the planet.

Now most electronic devices have their power usage info on them. Light bulbs usually have them on the bulb. Computers on the back of the power supply. It’s usually written on the brick that you plug into the wall when you charge your phone.

Lets just jump right in.  Take this 60W, 120V bulb on my desk(I don’t like florescent lights for desk work)  If I wanted to convert to amps I would simply  divide watts by volts.
60W/120V =  .5A

YEAH it uses .5A of power but that’s NOT what you’re getting billed for.  You get billed in Kilowatt hours.  So you have to add some time period.  
60W * 1 Hour = 60 WattHours = .06KWh

Now if we know that our electric company charges $0.10 a KWh
.06KWh * $0.10 = $0.006 an hour (or 1 penny cause you KNOW they’ll round UP) to run this 60W bulb for one hour.

Ok now for the formulas in a bit more organized format;

• Convert Watts and Volts To Amps 
  W / V = A
• Convert Amps and Watts to Volts
  A * W = V 
• Convert Amps and Volts to Watts
  V / A = W
• Convert Watts to WattHours (Wh) (T is time in hours)
  W * T = Wh
• Convert Wh to KWh
  Wh * 1000 = KWh
• Get the cost of our electrical appliance over time (R is your utility Rate)
  (W * T / 1000) * R = Cost

From this we can figure out pretty much the electrical cost of almost anything in our hour from looking at the little numbers on the back or bottom of the device.

I have 2 kid who have rooms at the top of the stairs and one really likes night lights.  I also have a disabled wife who needs light when moving about the house.  The way our house is situated we don’t get a LOT of outside light and leaving lights on all the time is NOT a good idea.  So in addition to replacing bulbs I got a bunch of LED night lights with light sensors. My daughter had a nightlight she loves so and was able to find a replacement LED bulb.

I used LED bulbs instead of incandescent and florescent bulbs for energy savings.  While an LED bulb may cost about $2.00 more it lasts 10x as long and uses 1/10 the electricity.  By getting lights with light or motion sensors the lights are ONLY on when darkness prevails.  This is also helpful in some rooms where the compact florescent bulbs take a minute or two to warm up.  You still have a bit of light.  

So far things have been good.  We can still see and we are turning off  more lights but not losing the luxury of illumination.  A stubbed toe is NOT a good thing.

I think my next step with this is to see if  I can get some Solar cells and run some of these lights from solar cells that gather light from the sun and interior lights. Recycling some used light how cool would that be?

To give an idea of the savings I’ll describe what I WAS doing.    Starting awhile ago I was running 1 60W bulbs 12 hours a day in the bathroom ceiling fixture as a night light (this would be on when people would be in the bathroom and during sleeping hours this costs about $30 a year.  I replaced this with a 14W CF which saved about $23 yearly.  Finally I used a 2 watt LED nightlight with a light sensor so it’s ONLY on when its dark.  Running this way costs less than $1 a year TOTAL. 

Another example in the downstairs bathroom I placed another one of these night lights.  Before we would keep the 2 14W CF bulbs burning as they would take about 2 minutes to warm up in the winter and just kept the habit up throughout the year.  This cost almost $30 a year the 2W nightlight runs about $2 a year.  Granted we DO turn on the overhead lights still but now we are in the habit of turning them off during the day and at night when we are not in the bathroom.  The warmup period is also not that bad as we have the nightlight to compensate. 

I created a simple form in a word processor to record the readings and type them into a spreadsheet to do the calculations.

The meter reading form has 7 columns. (You could get away with 4 but I have 2 meters to read)

• Date and Time
• Meter 1 Current Reading
• Meter 2 Current Reading
• Meter 1 Elapsed Time
• Meter 1 Revolutions
• Meter 2 Elapsed Time
• Meter 2 Revolutions

I also have a spot to write down the Meter Constant (I’ll get to that later)

The first three columns are pretty easy fill in the date and then read the meters.  I have one of the ones that simply shows the numbers rather than the dials.   The next four record the number of times the little disk goes around and how long it took.

The only other data that I’m collecting is the Meter Constant which is a number that is on the front beside the letters Kh.  This can be different from meter to meter but once you’re recorded it you don’t have to have it again.

Once I’ve recorded the numbers I then plug them into my spreadsheet.

I record the current time, and reading and get a change or the amount of power used since I last read the meter and I make a running total.

From there I get a bit tricky.  I then use the time and revolutions an calculate the RPM of the little disk (I take the revolutions and divide by time in seconds and then multiply by 60.  To get the actual watt hours I then multiply the RPM by the Meter Constant and then by 60.

To get how much money I’m using at the time I take the watt hours, divide by 1000 (getting kilowatts) and then multiply by the rate I’m paying per kilowatt hour.

It all sounds a bit complicated so I’ve created a spreadsheet to do the work for me.   I’m still getting the kinks out but I’ll post a copy when I’m sure that it’s bug free.