Not sure how feasible it is to roll this out large scale. There aren't that many stretches of water as lively as the pentland firth.
this post was submitted on 10 Jul 2025
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This is true, but I think the big thing is that this lasted as long as it did. Material science is important, and if we want Io scale these up for more general use we need to make sure they can at least survive.
Thanks to the power of two, a larger diameter blade could capture a lot more energy, and might be put in places with lesser tidal bores.
The problem is not that there isn't enough tidal power. The problem is that the pentland firth is both fast enough and deep enough. Orkney alone probably has enough tidal power to serve all of Scotland's needs, but most of the tide races are no more than 5 meters deep. The meygen turbine has a 18 m diameter so it's hard to find places that can support it in a way that doesn't pose a danger for surface vessels but also has a current fast enough to generate a meaningful amount of electricity.
If we’re going to get to 100m diameter tidal power systems in hundreds of meters of water we’ve got to start somewhere.
100 percent accurate because building benthic structures is incredibly hard. Having one with moving parts is even more crazy.
benthic
New word day for me!
Does ist matter? Even if its only a few places worldwide it makes sense ti develop them. Every bit of regenerative energy is important.
You could say the same about pumped storage hydroelectricity. There aren't that many places where you can store water on top of a mountain. Humanity still build a lot of pumped storage.
Not sure on the numbers, but in videos I've seen dozens of places where -all- the local power cud be tidally-generated, and I suspect there'd be hundreds of places around the world. Largely depends on the geology around the local tides.
For sure, but meygen is way too big for most fast moving tide races. And most places that are deep enough don't have a fast enough current. The pentland firth is unusual in that it is both deep enough and has a current in the order of around 10 - 15 knots in places. It flows like a relatively fast moving river. It's not a normal stretch of water.
One of the more badass sources of power. You've got uranium from supernovas, some form of captured solar energy, tapping the heat from the planet's core, or, in this case, directly slowing down the very rotation of the earth while pushing the moon away.
That planetary core thing will probably be quite a way off, tho it last for millions of years. But the whole planet is swathed in tides, in-and-out.
Yeah and any friction from tides(instead of free movement) slows the rotation and pushes the moon away. It's using the leverage of the gravity to perform work against the planet itself. Devices like underwater turbines, by extracting energy from the tidal currents, effectively increase this friction, which in turn amplifies the effect. The amount of energy naturally pulled out of this system is entirely dependent on the size of the tidal bulge and the shape of the seafloor/coast.
As for geothermal, we do use it, but only in hot spots.
Sit down sometime, make a realistic model of tidal power usage, and then figure out how long it'd before before 'the moon being pushed away' becomes visible. Once you can do that, then come back here and tell us about your calculations.
Of course the tides 'rubbing against' the Earth's surface have been 'pushing the moon away' at a far, far greater rate for billions of years. Big deal.
I also don't think that geothermal power installations stand to solidify the earths core and remove our magnetosphere. I just think it's cool that it's literally where the power is coming from.
Let's get it to 25 hours per day, I could do with a bit more time in bed.
Someone please calculate how much years of world energy consumtion is needed to move moon even 1 meter away. Or alternatively, how much Himalaya ranges in gravitational difference.
Tides go in, tides go out, never a miscommunication.
I wonder what the EROEI over projected lifetime is. Hopefully, comparable to generic hydro.