Others here have mentioned Russian gas as being a strategic weakness for Europeans and those within the Russian "sphere". America has laws against exporting oil extracted from the USA in order to protect its supply.
Similarly, India has announce that it is planning a (country-wide) GPS system so it's not subject to the whims of a foreign power. Europe is building the Galileo system and independence may be one of the reasons (though you can never tell with Brussels-originated schemes what the hell they are for).
The reason that Brazil (a Portuguese-speaking country) would want its own direct connection to another part of the Portuguese speaking world (viz. Portugal) doesn't have to be about cost - countries spend a great deal of money on "soft power" and building ties with their allies and $180Mil would just about buy you one shiny new fighter aircraft.
So it's not an unreasonable thing to do. It strengthens bonds, adds some self-reliance, gives a powerful northern neighbour something to think about and might even reduce ping-times to Portugal and the rest of Europe. If you're doing financial deals that alone could be worth the cost (there was a new cable laid across the Atlantic a few years ago that paid for itself by cutting 6mSec off traders latency).