Hydrofoil Surfing be it waveriding, kitesurfing or windsurfing is not strictly human powered. But it definitly is an interessting aspect of the hydrofoil sport.
Foil surfing is an amazing new sports and many even call it the future of water sports. Foil surfing allows you access to new waves and also offshore breaks that have never been riden before. It redifines what is considered a rideable wave.
Riding a hydrofoil is more like flying as the lift solely comes from the wings under the surface. So compared to a surfboard or any kind of normal boa you won´t actually feel any "bumps" when the water hits the bottom of your surfboard. You just glide through it and have a much smoother ride. The reason why you can ride much smaller waaves is also because you hardly don´t case any drag and though need much less push from the wave.
One of the first big waterman to make use of this new technology of foil surfing was Laird Hamilton. He surfed some of the biggest waves with foil boards and proofed it could be used in any kind of condition.
Which spots are suitable for foil surfing?
As you have an knifelike and very stiff wing attached to your board you really should be rather carefull and generally avoid crowed spots. Especially if you are just beginning. And the good thing is you don´t need to go to crowded spots to foilsurf anyway as the foil board allows you a much wider variety of spots and waves to choose from anyway.
Which waves are good for foil surfing?
You can barely ride any wave. As soon as you get on the board and ride the foil the drag is so minimal that even the smallest waves can be riden. Heck actually sometimes you don´t even need any wave at all and you can pump the foil board similar like one of the human powered hydrofoils for some distance till you catch the next wave. Kai Lenny has riden like 5 or 6 waves in a row like that.