No. They are not unique at all.
In my opinion they still are pretty unique because their efficiency is higher than 100%. Which was what I thought the sentence would continue with when I started reading it. Cannot be stressed enough. It's like magic :] Sure your LED is more efficient than your incandescent light bulb, but it still produces heat which is not intended nor really wanted. In my book there's no comparing that to a heat pump. That being said, not really a fan of such sentences either.