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Inspirational Maths


How much coal do you throw on the fire?
Would you be comfortable throwing another bag of coal on the fire and living amongst your smoke. Are the 'real costs' being hidden from you? How much coal does it take to do those little tasks?

Lets do some maths on a real world object and work it out. How about a 60 Watt light bulb staying on for a year.

60 Watts is 0.06 kW
1 year is 8760 Hours
That's 525.6kWh to keep the light on for a year(0.06 * 8760)
Thermal Energy of coal 6780 kwh/1000kgs
But normally only about 40% of that can be converted into electricity, thermodynamics being what it is.
That means 2712kWh takes 1000kgs (0.4 x 6780 kwh/1000kgs)
If 1000Kgs generates 2712kWh then 194kgs generates 525.6kWh.
194kgs for just one low wattage light bulb.


so 1 kg generates 0.368kW for a year (you could turn you 60W bulb on for a bit over 6 hours)
1 kW takes 2.712 kgs

That's without getting into Sulfur dioxide, Nitrogen Oxides, Carbon Dioxide and radiation.
And this is if the power plant is next door to you. Power is lost for every extra cm to your door.

Lets look at some common appliances and some time estimates to give you a better idea of you choices.



Making some informed choices when purchasing can make some big differences.
 

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