Every installation is different and will have different results. Climate, energy costs, building design etc will affect the overall consumption, and hence there is no warranty given by these comparison

How we calculated the costs:

Industry standard comparison

The energy consumption figures are taken from the catalog [current 2009] of the main competitors in Australia. These energy consumption figures may not represent the maximum or minimum consumption from the competitors, but  represent those which are most widely sold at the time.

Cost of Electricity

We have calculated the cost of electricity at $0.12Kw/h AUD. Customers who buy energy at wholesale rates may pay less than this.

Hours of consumptions

Emergency Exit signs and emergency lighting products are powered 24 hours a day, 365 days a year. Therefore number of hours that these products are in operation is 24hours x 365

Air conditioning costs

In commercial buildings the heat generated by the products need to be extracted adding an extra cost in running the products. We have used the ratio 1:2.92(1 watt of electricity removes 2.92watts of heat). This ratio has been taken form http://www.realclimate.org/index.php/archives/2008/06/wired-magazines-incoherent-truths/

For the calculations we have made the assumption that only 25% of the time will require air conditioning, where as during the other times, it is either too cold or night time and unoccupied.

CO₂ savings/ emissions

The total energy savings calculated are converted into CO₂ savings based on an energy mix of 0.5 kg CO₂/kW. Countries that have higher reliance on coal will have higher savings.

The math

Power consumption (Watt hours) =      (Energy consumption of product per hour x 24hours per day x 365 days per year) + [{(Energy consumption of product per hour x 24hours per day x 365 days per year)  /2.92} x 0.25]

CO₂ Produced(kg) = Power consumption(kw) * 0.5

Energy Cost per year($AUD) =  (Power consumption/1000) x $0.12AUD