but I can't see how it copes with the variation in sea level from the tides (no obvious explanation from their site: https://www.ecowavepower.com/ ). The pivot point looks fixed in the pictures. Anyone know what happens? Is it restricted to small-tide locations, or can the pivot move up and down somehow?

it looks like they can accommodate a quite wide range of water level. Enough to allow for tides, I dunno?

so what you have to accommodate can be quite different (as for the Bay of Fundy ... )

installing longer stroke cylinders pretty much any tidal height excursions could be accommodated. Or, ratchet the whole thing up and down.

It's an intriguing idea.

It seems to me that tidal variation could be built in on later models.

Just spitballing, but my experience as an engineer tells me that they are using this as a proof of concept model, and additional features will roll out in future installations.

Unfortunately, the only way to quit fossil fuels is to quit fossil fuels. Quitting fossil fuels is a lot like quitting smoking. Cutting a few cigarettes out of your two-pack-a -day habit by vaping or chewing a stick of nicotine gum doesn't make you a non-smoker.

Another problem with projects like this is that they can't produce electricity continuously or on demand thus they can't displace fossil fuels entirely, which is what we need to do. The amount of batteries of other energy storage required to make these kinds of "renewable energy" available as needed is completely ludicrous. These projects are not economically viable without fossil fuel backup. Usually this fuel is natural gas. Overall batteries waste energy but are useful because they allow fossil fuel plants time to fully power up when a renewable energy source drops out. (A certain number of gas power plants are kept running continuously to stabilize the grid even when renewable energy is at its maximum. An unstable grid results in massive power outages like Spain recently suffered.)

This is how the grid works in California -- we have lots of renewable energy, battery backup of around a hundred minutes, and gas picking up the load whenever the sun isn't shining, the wind isn't blowing, or in this case, the ocean is calm.

You can watch the California grid in action here:

https://www.caiso.com/todays-outlook/supply

and see its performance for the last 12 months here:

https://app.electricitymaps.com/zone/US-CAL-CISO/12mo/monthly

If California was willing to build nuclear power plants we could shut down our natural gas power plants entirely, reduce our greenhouse gas emissions substantially, stop trashing our wild places with wind turbines and solar panels, and not bother with Rube Goldberg energy projects such as this.