CIPK can be considered the prime number of energy, and it is especially important with electricity. Our ability to adjust the proportion of clean versus polluting fuels and technologies when generating electricity makes electricity unique as an energy source. To make electrcity cleaner on an energy-unit basis, that is, to make electricity CIPK as low as possible, we simply need to increase the proportion of clean to polluting generation.

It is not possible to do this with other sources of energy, such as fossil fuels. For example, when we burn natural gas for heat we cannot avoid producing at least roughly 200 grams of carbon pollution for each kilowatt-hour of heat energy from combustion. In the case of gasoline, we produce at least roughly 250 grams of carbon pollution for each kilowatt-hour. This is simply unavoidable.

The chart in this section shows the carbon pollution per kilowatt hour of energy from various fuels as well as from the New York, Ontario, and Alberta electricity grids. You will note that the CIPK for each of the three electricity grids fluctuates hour by hour—this is because the fuel mix for each grid itself fluctuates hour by hour (see previous section). However, CIPKs for the other fuels (coloured in darker gray) do not fluctuate; they remain fixed where they are today. This reflects the physical and chemical realities associated with burning them in a nitrogen-oxygen atmosphere such as ours.