Smart Boards, like any other computer component, use energy. With the cost of electricity soaring and resources like oil dwindling, energy consumption has become a major concern for many people. Power usage can be calculated using a couple of simple formulas, depending on the information available.
Things You'll Need
 Calculator or pen and paper

Determine the wattage used by the Smart Board. This is usually located either on the back of the device or in the manual. Refer to the Tips section if the wattage is not listed.

Multiply the wattage by the number of hours per day the device is used. (Watts x Hours per day)

Multiply the product of wattage and hours per day by the number of days the device is used per year. (Watts x Hours per day x Days used per year)

Divide the result of (Watts x Hours per day x Days used per year) by 1000. This gives you the total power consumption per year in kWh. The formula used is: (Watts x Hours per day x Days per year) ÷ 1000 = kWh

Use the wattage provided in the Smart Board spec sheet, an average of four hours usage per day, and a speculated 100 days of usage, and the equation plays out thus:
([1.5 Watts x 4 hours] x 100 days) ÷ 1000 = kWh per year
([1.5 Watts x 4 hours]) = 6 Watt hours per day
(6 Wh x 100 days) = 600 Watt hours per year
600 Watt hours ÷ 1000 = 0.6 kWh per year
Tips & Warnings
 The wattage listed in the specifications for the 680 is 1.5, and this number seems to be the same across the line of Smart Boards.
 If the wattage is not listed, you can determine it using the voltage and current draw, listed in amperes. The formula is (Amps x Voltage).
 If the current draw is not listed, you will need to use an ammeter to find it. Ammeters can be bought in most electronics stores.
 If your device is plugged in, it is likely still drawing power. Use a power strip's switch or unplug the device to stop this drain.
References
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