[IshKebab]

Definitely seems more feasible than a lot of crazy energy ideas! E.g. I think this makes more sense than the air versions because you don't have problems launching/landing or when the wind stops.

Probably the biggest issues I could imagine are maintenance and wildlife. They might be minor issues though. Also in most of the world (maybe not the Faroe Islands) this has to compete with solar & batteries which are getting cheaper and cheaper. If this is more than £5-10m then I think solar and batteries would be a much better option in most of the world.

[Someone]

> Probably the biggest issues I could imagine are maintenance and wildlife. They might be minor issues though.

Might, yes, but I think it’s unlikely all problems will be minor. Salt water isn’t kind to metal, no matter how well painted. Also, I expect barnacles will start growing on it. If you’re a filter feeder, this may be even better than sitting on the sea bed or on a whale.

Question will be how much that effects their $/MWh calculation. The only real way to find out is to try, I guess.

[usrusr]

The good news is that we do have a bit of experience with metal machines that operate in sea water for decades. We (as in humanity, I don't) know exactly what to expect. You'd want to have a permanent service operation scaled exactly to how much overhauling capacity you need to put the tide kites in a round robin maintenance loop.

[hoseja]

And yet, every other tidal powerplant has been rendered hopelessly useless by barnacles.

[usrusr]

Have they? And how many of them can be ordered to surface under tide power, for easy maintenance access and towing into a maintenance dock without involving expensive divers?

I presume the tether on this would be built long enough for controlled surfacing, a longer tether means larger deadzone between inbound and outbound tide, but there won't be much energy in the flow close to the turning point anyways.

[Sammi]

We are perfectly capable of removing barnacles from ship hulls. What makes these kite hulls different?

These are just fancy boats you know.

[Brian_K_White]

Maybe we don't even care if barnacles grow on it since it's kind of a water catcher anyway.

Or if not this design, maybe one could be designed to either not care or even benefit from barnacles.

Remove the whole problem of fighting it.

[leoedin]

The huge difference between solar and tidal energy is the predictability. Tides can be predicted in advance - you always know exactly when and how much electricity you'll get. That's really valuable in a world of increasingly volatile electricity supply.

Solar will probably be far cheaper per installed MW (although capacity factor will be much lower), but batteries are still a long way from being cost effective. The cheapest batteries right now cost $100/kWh or $100k/MWh. Battery costs are still falling, but the curve is levelling off.

That price means that time-shifting 1 MWh of energy a day for 10 years would add $27 per MWh to the cost of electricity (ignoring ongoing maintenance costs, and assuming a 1MWh battery can do 4k cycles). The company behind this is forecasting $50/MWh of generation. Solar on its own right now sits at $30/MWh, although presumably that's for places with relatively high capacity factors.

The limitations are obvious - this is very geographically constrained. I suspect there will be a small place for this type of technology in the renewable mix - especially in remote and northern places. Then again, offshore wind is already sitting at below $50/MWh and doesn't have the same geographic constraints - so maybe it's a better bet.

[Tarq0n]

I wonder to what extent its output correlates with that of wind energy in the same region. Having a reasonably independent set of generating technologies might help with the intermittent generation of sun-based renewables.

[Super_Jambo]

I guess power output will basically be the derivative of this tidal height chart: https://www.tide-forecast.com/locations/Gamlagatt-Faroe-Isla...

The steeper the slope the higher the power output.

I think the real question on tidal generation is how costly is maintenance. The sea is just a very unforgiving environment. Salt water and marine life fouling everything are difficult engineering problems that just add more expense than I can imagine wind turbines having.

If they can make tidal work I guess we'll end up in a world where most of their profit comes from keeping the grid alive when it's a calm and there's no sun.

I guess this may mean these technologies aren't going to really take off until we stop using hydrocarbons to make up the shortfalls...

[justsomehnguy]

> maybe not the Faroe Islands

Capital and largest city:

Tórshavn, 62°00′N 06°47′W