Like the author says, Megawatt is a measurement of energy wasted per second.
If we take his claim that 10 MW is being wasted, then the energy wasted at 10 MJs⁻¹ over a year is the energy of 5 small atomic bombs.
If we take his claim that 10 MW is being wasted, then the energy wasted at 10 MJs⁻¹ over a year is the energy of 5 small atomic bombs.
http://www.wolframalpha.com/input/?i=10MW+times+a+year+divid...
Ratios matter, large numbers without a relevant basis for comparison on the other hand are just misleading. There are roughly 116 million households in the US, saving the energy of 7,500 is not a big change.
You're solving roughly 1 - 15,466 th of the problem. And that's assuming that all the savings could even be applied to the US, which they most certainly couldn't.
That's not a big impact. Chances are no-one - even if they were looking - could notice the figurative needle move on a change that small at all the power-stations serving the aggregated demand.
Scary numbers though even if they are ballpark figures.