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theone

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## Homework Statement

Using the above result, estimate the annual CO2 emission savings (in kg/yr) associated with replacing one 60W incandescent bulb with one 13W fluorescent bulb, in one typical Canadian household. Do this calculation from “first principles” using the following assumptions:

(The "above result" was the answer to "How many hours per day must the replacement and original light bulb be left switched on (on average over the year) to save a certain amount of money per house". The answer was found to be 4 hours)

- The GHG savings are entirely CO2 and result from the reduced combustion of fossil fuels in electric power plants.Canada’s electrical power generation mix is 23 % from fossil fuels. Assume electricity from other sources (hydro, nuclear and renewable) have approximately zero carbon emissions. The carbon intensity of this fossil fuel usage is 22 g/MJ

- Assume the overall efficiency for the fuel energy to electrical power conversion process is 35 %

- Most light bulbs are located indoors, in an occupied living space. So, the net carbon emissions savings will be approximately zero for six months of the year.

## Homework Equations

## The Attempt at a Solution

Is the answer:

so (60-13)= 47W worth of carbon emissions is saved by replacing the bulbs,

47W=47 j/s so

47 j/s * (4hours*3600)s * 22(g /MJ) * (1MJ/10^6J) =

14.9g

since carbon savings is zero for half the year, then 14.9/2

= 7.45g?

I'm not sure where to use the info of 35% or 23%?