Sunday, April 14, 2013

A Little Stuff Goes a Long Way

How much uranium is required to power an average home in the USA for a full year***?
According to Energy Efficient Homes for Dummies by Rik DeGunther, the average North American home consumes 8,400 kWh in a year.
Since 200 tons of natural uranium produce one GWe of electricity for a full year*, grinding the numbers we arrive at the following figure: 192 grams of uranium per year (less than 7 ounces). As a reference, the iPhone 5 weights 140 grams. Considering that uranium is 70% more dense than lead, this is indeed a very small amount (around 25% more volume than the one occupied by the current iPod Shuffle).
Now, let's compare this to the amount of coal that would be required for the same purpose**** (today, close to 40% of the world's electricity is produced with coal).
According to How Stuff Works, one kilogram of coal produces 2.70 kWh of electricity**.  Making the math we arrive at a total of 3,111 kilograms (6,800 lbs) to power the same typical North American home (PLUS more than eight tons of carbon dioxide emitted to the atmosphere).
We are talking of many orders of magnitude of material difference!
The mass of coal required is 16,200 times larger than the equivalent amount of uranium, but since the density of coal is only 1.1 to 1.5 grams per cubic centimeter (vs. 19.1 for uranium), the VOLUME of the needed coal would be at least 206,000 times as great as the equivalent uranium volume.
We are not saying that uranium is clean, but considering the amount of material that has to be mined, transported and finally "burned", uranium is cleaner (actually, much, much, much cleaner) than coal.
Oh! and did we mention uranium powered utilities produce almost no CO2 during operation?


*** In a nuclear power plant.

**** In a coal fired power plant.

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