–noun, plural - houses
1.Electricity. a generating station.
2.a person, group, team, or the like, having great energy, strength, or potential for success.
In Basenotes terms? Loud fragrances, with lots of sillage and longevity, but here on Basenotes is often reserved for strong mens fragrances from a time before the aquatics boom of the '90s.
So, it can be as much a style than a matter of strength. A*Men is certainly strong, yet rarely do people call it a powerhouse, for some reason.
The fragrances typically referred to as "powerhouses" here are fragrances from the late 70s all through the 80s that are very strong and often feature prominent notes of pine, patchouli, musk, and oakmoss. Some examples of the style that are widely available for testing are Korous, Paco Rabanne Pour Homme, Bijan for Men, Aramis, Grey Flannel, Quorum, and Versace L'Homme, all of which could probably be found at a mall Perfumania if you want to make yourself familiar with the style.
Some people just use the term "powerhouse" to describe a very strong scent in general though. It's usually used to describe the former definition though.
Powerhouses could exist in any era of perfumery, but most commonly refer to those in the 70s and 80s-- 1970s and 80s that is (not dandified Victorians now). They usually are considered "classics" and display a lot of sillage like Givenchy Gentleman for example.
You know your cologne is a powerhouse when you walk by somebody at the office and thay say, "Whoa! Dude." And then they say, "Hey, that smells pretty good. Wait, my dad wears that. Cool."
Creed's Bois du Portugal is the essence of a power house fragrance.
Long lasting power and great sillage fragrances.
Sometimes I hear it used to refer to really strong fragrances that were made in the late 70s/80s. Other times people use it just to describe a strong fragrance in general.
Smell the Original Polo, Quorum, Kouros, or Azzaro Pour Homme and you will know what people are talking about when they say 70s or 80s "powerhouse". That stuff will make you grow chest hair.