Electric surfboards, the fastest-growing segment of yacht toys, make it possible to carve waves in even the flattest conditions.  Most foil-less e-boards don’t really look much like a surfboard, but still deliver a fast-running, hard-carving surfing experience, thanks to compact electric motors.  The explosion of e-foil designs, from oversized models with handlebars for beginners to sleek, low-volume boards for advanced riders, has been remarkable in just two years. “Hydrofoils need less power and lighter batteries, so they extend run times,” notes David Trewern, founder of Fliteboard, one of the original e-board manufacturers. “It’s hard to beat that feeling of riding above the water.” A dozen competitors are looking to carve up their own slice of the market with feature-rich models for beginners to elite riders alike. Here are six of the big kahunas.