Humanity has never faced a more monumental challenge. After two centuries of burning fossil carbon, trashing the atmosphere, pushing Earth systems to the edge of collapse, industrial societies need to develop other sources of energy that are renewable and clean.

The prospects are frightening, but climate angst has an antidote.

Wind and solar, for sure.

There’s another vast storehouse of energy on half the world’s doorstep — Earth’s oceans.

Covering three quarters of the planet’s surface, they store colossal volumes of heat, that can be tapped.

So can the kinetic energy from ocean waves and tides.

This past spring, in the Dutch capital of Den Haag, several hundred entrepreneurs and engineers came together to showcase innovative devices for doing just that, at the annual gathering of Ocean Energy Europe.

Listen to some voices the GPM gathered. Click on the play button above, or go here.

Alejandro Marques de Magallanes Crespo, founder of Magallanes Renovables

Talking about the energy of ocean tides — rising and falling like clockwork, under the influence of the moon — no better place to tap this colossal energy resource than the Shetland Islands, on the northern tip of Scotland, and in the Bay of Fundy, between Nova Scotia and New Brunswick, in eastern Canada, home to the highest tides in the world.

That’s what a company called Nova Innovation is doing. Simon Forrest is founder and CEO. In a quiet spot on the margins of last spring’s Ocean Energy Europe conference, in The Hague, the GPM sat down for a chat with Simon.

Petit Passage, on the Bay of Fundy, where a Nova turbine will soon generate tidal energy

Conferences are fun. Lots of interesting people to meet and sessions to attend.

Better still, heading out into the field. Especially if it’s North Holland. That’s where the GPM went, last spring, on a bus trip organized by the Dutch Energy From Water Association, together with forty ocean energy innovators from around the world.

Our first stop: Den Helder, at the manufacturing facility of Symphony Wave Power, to see their wave energy demonstrator. Fred Gardner is Symphony’s founder.

Listen to our conversation in today’s podcast. Click on the play button above, or go here.

Rik Siebers, Director of REDstack, showing small-scale model of reverse electrodialysis

Of all the forms of energy readily available to coastal communities around the world, none is more intriguing than salt.

To be more precise, salt gradients. Wherever fresh river water flows into salty ocean, that freshwater gets infused with sodium, calcium, chloride and sulfate ions, and salt gradients form. Make this happen across a plastic membrane, under controlled conditions, you generate electricity.

Reverse electrodialysis, it’s called. No better place to see this in action – indeed, the only place – than the Afsluitdijk. Check it out on a map. It’s that long highway, built on a dike between the Dutch provinces of North Holland and Friesland, separating the freshwater Ijsselmeer from the salty Waddenzee.

Afsluitdijk

Right in the middle of the Afsluitdijk, a company called REDstack is bringing fresh and saltwater together, and putting electricity into the Dutch grid. RED stands for Reverse Electrodialysis.

The first voice you’ll hear is Peter Scheijgrond, Chairman of the Dutch Energy From Water Association, our tour leader last spring. Then Rik Siebers, REDstack’s Managing Director and Michael van Oostrom, Head of Market Development.