RicodJour said something like:

....[snip]...

This is another example of bad advice. A larger tank is less
efficient and has a lower efficiency factor. Smaller tanks have an EF
of ~.63 so you're ****ing away a third of your dollars. A larger
tank's EF can be in the neighborhood of .50 Oversizing a system so
you can waste more money is the exact opposite of good advice.

I'm not sure I understand this. Efficiencey in engery loss per gallon
should be lower (at least in physics, larger volumes have less surface area
per unit volume). Unless efficiency in EPA terms is different (is it?)

....[snip]...