Rough Crossing: Britain’s Tidal Powerhouse


At the other end of Britain to wild and wonderful Cornwall is one of my favorite places in the world – Orkney, a windblown, wind-sculpted scatter of islands off the brink of Scotland. Orkney is a beautiful and welcoming place to live and work in…but first you have to get there. The last hurdle in the formidable land journey up from England is the Pentland Firth.

“The Pentland Firth is well-known by seamen as one of the worst stretches of water in the world.”

– James Lake, quoted in Scapa Flow (1968)

It’s 1995, and I’m visiting Scotland with my uncle. I’ve only vaguely heard of Orkney (is that in Norway?) so we grab sandwiches and a flask of disgustingly stewed coffee and drive the hundred miles to John O’Groats. In late February it’s the perfect departure point, because you instantly want to leave it – nothing but a bleak collection of buildings huddled as close to the ground as modern architecture will allow, and beyond, a gunmetal-grey sea churning angrily against the harbor walls.

I’m having second thoughts. It’s the way the approaching ferry is rolling, lurching and occasionally disappearing altogether. I manage to convince myself that it’ll be fine once we’re out there. I’m wrong – it will be one of the most terrifying experiences of my life.


The Firth is the point where the North Sea and Atlantic, foiled by the length of the U.K., finally manage to vent their fury upon each other. Every day, two tidal surges of astonishing power race up and down this sea lane at speeds of up to 16 knots (30 kph), creating currents and whirlpools with delightful names (“The Swelkie”, “The Merry Men of Mey”) that belie the fact that this waterway still claims lives, even today.

The potential for renewable energy is obvious, leading to the strait being dubbed the “Saudi Arabia of tidal power” – it’s been estimated that it could generate 25% of the tidal energy potential for the whole of Europe. There are already proposals for how that might happen, such as this one by TidalStream.

We’re halfway to St. Margaret’s Hope, and I’m suspecting that her hope was to get there without losing her mind. The boat is riding up one wave, poising at the top, then smacking down into the water like it’s been dropped from a crane. My uncle’s loving it, which he shouts to me with sadistic glee. Mentally I’m in a whole different place, possibly writing my will. There’s only one photo of me from that journey, and my face is an improbable shade of lurid green.

If all this roiling power can effectively be harnessed, the Pentland Firth could supply a significant percentage of the UK’s future energy needs. But taming it? I’m sure we can’t – just as I’m sure I’ll never again try crossing it in February.

Images: Hamed Saber, foxypar4

Mike Sowden

Mike Sowden is a freelance writer based in the north of England, obsessed with travel, storytelling and terrifyingly strong coffee. He has written for online & offline publications including Mashable, Matador Network and the San Francisco Chronicle, and his work has been linked to by Lonely Planet, World Hum and Lifehacker. If all the world is a stage, he keeps tripping over scenery & getting tangled in the curtain - but he's just fine with that.