To remind, the MeyGen project’s Phase 1A involved the installation of the AR1500 onto a gravity-based foundation, alongside three other AH1000 MK1 turbines, to form an array of 6MW.
From what I've found, the AR1500 has just had routine quarter-life maintenance[2], but I can't find anything concrete right now which of the four made the 6 year milestone. I do note that in the brochure[3] for the AR1500 they claim three service intervals every 6 1/4 years, rather than four service intervals as indicated by the article.
[1]: https://www.offshore-energy.biz/simec-atlantis-troubleshooti...
[2]: https://www.offshore-energy.biz/overhauled-meygen-turbines-t...
[3]: https://simecatlantis.com/wp-content/uploads/2016/08/AR1500-...
If 1/4 make it then you at least know it can be done and hopefully learned a couple key failure modes from it
From that link:
"The first of these turbines is scheduled for redeployment in May 2022, with the final turbine to be deployed in March 2023, complete with a retrofitted wet mate connection system, which more than halves the costs of future turbine recoveries and deployments."
"The company’s AR150 turbine was re-deployed last month, after being out of the water for upgrade and maintenance work."
The single long-running turbine can be compared to the upgraded turbines to measure the effect of the upgrades, and it provides the headlines this thread is about. The upgrades themselves are also clearly valuable R&D work.
> complete with a retrofitted wet mate connection system, which more than halves the costs of future turbine recoveries and deployments."
Why do they need recoveries if not for maintenance? Why did they need to cut the cost of maintenance if no costly maintenance were needed?
> after being out of the water for upgrade and maintenance work."
How is this not literally validating GPs comment?
Anyone can say "the new ones won't need maintenance and the only reason we took them out was to improve them", but they could've worked on better ones and deployed them without removing existing ones. Removing existing ones mean they broke. So until the new ones last as long, GPs analysis is the correct one.
Upgrades. Was already answered.
> Why did they need to cut the cost of maintenance if no costly maintenance were needed?
To improve the ROI. If maintenance is needed, it will be cheaper going forward. How often the average turbine will require maintenance is harder to determine based on the information available. We know it might be somewhere between a few years and ~6 years.
> How is this not literally validating GPs comment?
It does not say anything about maintenance being required or costly.
> Anyone can say "the new ones won't need maintenance and the only reason we took them out was to improve them", but they could've worked on better ones and deployed them without removing existing ones.
That requires more investment (the things ain't cheap), and it does not show whether successful maintenance is possible or how expensive/cumbersome that maintenance would be, which are very important pieces of information for determining ROI.
If you made 4 loaded dice and continuously rolled them for 6 years and 1 of them consistently rolled a 6 everytime then yes, it is entirely possible.
I'm hoping for a good renewable energy source as well but that doesn't mean I have to accept shoddy statistics.
1.5 MW is nothing to scoff at, so if it costs a bit in maintenance that's okay. But overall costs would be great to know.
Sure, there are many parameters to consider, but it's the kind of thing energy analysts do all the time.
The article likely double-dips on this by saying that 6MW could provide for 7k homes, which it obviously can’t at peak use.
Also I would say the expression "powering a home" usually implies average demand not peak demand.
Assuming these turbines are always at nameplate production, which they are not, they produce 6MW. Spread among 7k homes, that’s less than 1kW, which is not a lot.
Given the previously stated peak of 2.6kW per household, 6MW would cover about 2300 homes.
The only way you could get to this kind of number would be if you calculate the average use for a household over a year. But then you would have to compare it to the plant’s yearly production rather than its nameplate capacity.
Wikipedia quotes MeyGen at 10.2GWh in 2023, that means 1.14MW on average instead of 6MW. Assuming perfect storage, that would mean an average of 163W per house for 7000 houses. That is barely enough for a fridge.
> Also I would say the expression "powering a home" usually implies average demand not peak demand.
That's my issue. Comparing average demand to nameplate capacity is dishonest.
An efficient European fridge uses less than 250 kWh/a, or less than about 30W on average.
E.g. this uses 127 kWh/a: https://www.bosch-home.com/de/de/product/kuehlen-gefrieren/k...
[1] https://www.ofgem.gov.uk/information-consumers/energy-advice...
[2]: https://assets.publishing.service.gov.uk/media/67e3eae39c9de... - see background section
In many countries, 1kW is more than enough to cover electricity usage in a household. https://ec.europa.eu/eurostat/statistics-explained/index.php... says “Electricity consumption per capita in the household sector in the EU in 2022 was 1.6 MWh per capita (1 584 kWh)”.
That’s about 4.3kWh/day or 180W. https://ec.europa.eu/eurostat/statistics-explained/index.php... says there were 202 million households in the EU in 2024, on a population of about 450 million, or 450/202 ≈ 2.2 persons/household.
So, on average, a household in the EU uses less than 500W of electricity.
If you want to compare power use of a household averaged on a year to yearly production of these turbines:
- 1.6MWh * 2.2 people per house = 3.5MWh/household
- 10GWh produced in 2023 / 3.5MWh = ~2860 households supported.
> The actual statement is "producing" 1.5MW.
I have no doubt that the author could write that. My message points out that it simply is not true.
[1]: https://simecatlantis.com/wp-content/uploads/2016/08/AR1500-...
For instance, there's the https://www.esig.energy/wiki-main-page/general-electric-1-5-..., which has ~40m blades. The AR1500 (which is what these tidal generators are using) is smaller, with "only" 9m blades.
So it's significant in that these aren't toy devices, they fit in a very similar place in the engineering ecosystem as conventional wind. They should be a real competitor.
GE's 1.5MW models are 20 years old.
Private, entirely for profit companies, have recently answered large government tenders in the middle east to sell power at the equivalent of $0.05 USD per kWh. They are fairly confident that they can make a profit doing this, even with the cost to incur the long term debt to privately build a massive solar power plant.
The cumulative amount of solar power being produced within Germany right now is a good example of its practical use in a less sunny climate.
In terms of placing things in the ocean, hiring the sort of offshore work vessel with a built-in crane can go and place or remove multi ton apparatus is very costly. Maritime construction for things like laying coastal submarine cable, building piers and docks and marinas, setting and maintaining marker buoys isn't cheap.
Laying and maintaining HV AC or DC submarine cables in salt water is also particularly known to be expensive. Hiring a 36'-42' aluminum landing craft for coastal construction projects, with fuel and crew can be easily $500 an hour.
Labor and vehicle costs are greatly increased compared to doing things on dry land.
Having different types of power generation provides redundancy. The wind still blows at night, the tide still comes in and out when its cloudy, etc. Grid storage is nowhere near a solved problem, so something like tidal could prove less expensive than storage or overbuilding alternatives to overcome their variability problems. Even if it doesn’t end up being widely useful, it could still end up finding a use in more niche applications.
Finally, it can and will improve. 30 years ago, solar was not price competitive and decades of development and iterative improvements have changed that. We should keep developing alternatives to see their full potential.
Doesn't even need to be less-useful land (especially in western Europe, ground is becoming a scarce resource), put PV on flat rooves or add them over open car parks. Also helps alleviate pressure on the overstressed energy grid by generating and using power more locally.
But, local power is (overall) a lot more costly than major centralized power generation projects, like a wind farm or what have you.
Eg: https://www.next-kraftwerke.be/knowledge-hub/balancing-marke...
Not sure if this is prominent in the Irish market or not
all systems require maintenance, so "costly" is relative; would need more specifics to determine whether this is a cost effective solution or not
How do the maintenance costs (and intervals) of these compare to gas/steam turbines?
The resins used for carbon fibers are usually very bad at contact with water over long periods of time. Even those in aerospace applications require coating/paint if exposed moisture over time. It’s a plastic, even the best ones don’t do so well in water after a few months.
Furthermore, the damage that moisture does to the resin can be difficult to detect and even more difficult if not impossible to fix. It requires clean rooms, skilled labor and machinery that you don’t have in the middle of an ocean.
Then take iron corrosion: it is easy to spot by naked eye, it may not be easy to repair, but it is relatively simple to “halt” further damage by removing the rust and adding new paint.
Don’t get me wrong: carbon fibers are amazing, but sometimes the “boring” solution is best.
PS: steel alloys and coatings can be amazingly high tech too, it’s amazing what can be engineered.
https://www.popularmechanics.com/science/a60687211/titan-sub...
Also, I am thinking about all the ocean factors beyond salt corrosion. There's tons of crap in the water beyond salt and minerals. Like fine grit suspended in it. Plus the tidal forces etc.
While rust can be a problem it can be mitigated. Also steel is easier to repair than many other materials (welding).
BTW. Aluminium does suffer from corrosion as well. I used to have racing bike, the wheel nipples (these connect the spokes to the wheel rim) used to corrode to the point where they would fail, which meant I would end up with a buckle. I ended up having both wheel rebuilt with higher quality brass nipples.
Plastics under time also suffers from a different set of issues. Plastics can become brittle. Anyone working on old computers (especially macs) can attest to this.
As opposed to other forms of energy production which have free/zero maintenance?
It's a nice idea but costly compared to solar even in places like Scotland.