In September at the annual Cannes Yachting Festival, Dominator Yachts introduced the D26 Ilumen, an 87-foot semicustom model that uses hybrid propulsion. Though it has not yet been built, the yacht—which took two years to develop—presents specifications that are indeed promising, both in terms of design and performance.

Its four power modes range from pure electric, which engages the electric engines and enables the yacht to travel silently at speeds up to 6 knots, to diesel and electric, which engages both…