I’ve always been fascinated by boats which seem to defy the laws of physics, and naval architect Nigel Irens has been responsible for more than his fair share of them. Long before fast displacement vessels became a thing, he was busy designing slippery low-displacement motor boats that only needed unfashionably small engines to spirit them along much faster than their theoretical hull speed should allow (1.34 x the square root of the hull length in feet). His 39ft Range Boat, for example, has a theoretical displacement speed of just 8.4 knots yet it can sustain a 14-knot cruise from an 80hp engine while burning just 17 litres per hour.
Now he’s at it again, only this time on a smaller and even more sustainable platform. His latest Clara series of boats are 26ft open launches made of marine ply that can cruise at 12-14 knots using a 20hp outboard, as he demonstrated by driving one from Dartmouth to Southampton in 9 hours for the recent South Coast Boat Show. This also makes them ideally suited to electric power but one rather well-known owner, the writer and television presenter Richard Stilgoe, has gone one step further and fitted his with solar panels as well.
To test how well it worked, he arranged a shakedown cruise on the River Avon from Tewkesbury to Stratford and invited his grandchildren along for the ride. I won’t tell you how it went because you can read his much more entertaining account of it on
