That's assuming that you could get the power consumption down to zero, which is impossible. While a penny was an exaggeration, a 5W power savings over a month is about 50 cents savings on someone's power bill.

Yep, for me it would be $8.50.

For reference, this is an order of magnitude greater than the typical power consumption for existing satellite dishes / 4G modems, which typically operate at around 10W of power consumption.

For reference, most existing satellite dishes are receive only, and 4G modems only have to close link on a tower a few miles away, and at RFs where atmospheric attenuation is much lower.

Huh? You think existing satellite internet is receive only? How exactly would the web work in such a system?