From Reddit:
Solar, wind, and wave - ok.. why the hell is no one talking about tidal energy?
There are loads of talks about how solar and wind energy alone aren't enough if we really want to move towards clean energy. Yet there's more and more chatter about building more solar and wind farms and investing in these renewable sources - while we all know we need a mix of different renewables to really make a difference. It's the same old story for everyone - the sun doesn't always shine, the wind doesn't always blow... yea yea... you can see it especially in the UK where wind energy drops off dramatically during the summer.
I have looked into this before because Inwas curious. One problem is that tidal doesnt have that big effect evenly on the globe.
But I have seen some pretty cool tidal power plants on Youtube and there are actually a few in use worldwide.
Off the top of my head, I would say a barrier is the distance between where the energy is created and where it is consumed is far. Unless we are dealing with something close to shore, then it is going to require the energy transported.
I havent looked but this could be done in big lakes because they have tides.
This one is cool on farose island.
I've been following CorPower Ocean's journey (https://corpowerocean.com/a-short-history-of-wave-energy/) for a while now, and I'm really chuffed about their recent big investment. While I'm glad there's more discussion about ocean energy, I really feel there's a lack of talks about tidal energy. Tidal energy is predictable and reliable, and I know some people say it's not always there, but as long as the moon and gravity exist, tides are pretty much always around - not like waves, solar, wind, etc., which depend on the weather.
There are already some great tidal energy technologies that can produce clean and, most importantly, reliable energy - like Orbital Marine Power, Nova, and my favourite one because of their shell design and technology that's completely 3D printed and, as I understand it, much cheaper than other technologies - Spiralis Energy (https://www.spiralis.energy). Yet, they all lack investment, and more importantly, tidal energy itself isn't getting the buzz it deserves, even though it could be a really big deal.
Just trying to understand the cons of tidal energy, and why the hell we don't hear more talks about it from climate change advocates, politicians, and "big leaders."?????
There's literally a section on the first website you linked that explains why wave power isn't bigger. In the past it's been too expensive, low energy production, prone to corrosion and failure, and difficult to maintain.
Storage is the solution to the sun not shining and the wind not blowing.
seriously. so many people have little idea how insanely corrosive salt water is, especially on moving parts. tidal output just doesn't produce enough to cover the cost to maintain it.
This is literally the answer.
Different attempts have been trying to convert tidal and wave motion into energy for decades and the issue has always been corrosion and maintenance, and the costs related to both. The closest I've seen to a simplified energy capture device are those wave motion devices that move back/forth from ocean currents similar to how sea weed or kelp move. Grid connection and storage are both still a pain, but at least it's not a turbine in salt water.
It's like mineral oil cooling for PCs. Yes, it's doable. No, it's not worth it except in those rare edge cases.
The conventional wisdom regarding the ocean is that if you put ANYTHING in the ocean, the ocean will eventually destroy it. This logic has, for the most part, remained true over time.
Ask anyone who owns or works on boats how destructive the sea is. The internet is wildly optimistic about wave/tidal power, far cheaper to put a turbine on the top of a pole 100m above the water than to put all the expensive moving parts in a corrosive liquid that's trying to rip it apart 24/7.
Wait, “for the most part”? What nameless horror of the abyssal depths has defied that?
There's at least 2 posts per day here about tidal energy....most of it gets removed because there's no new news...perhaps you should investigate your sources of information?
North of england theres an island group where alot of companies test out there tidal technology. Theve been there for years now
We've mastered the wind and sun. The ocean is still beyond us. The unfront resource commitment to install the tech then maintaining a moving piece of equipment submerged in salt water.
Even structures with little moving parts like sea labs are abandoned after a decade or so because it just doesn't become feasible to maintain anymore.
Just like solar we'll start taking it more seriously when there's a promising feasible piece of tech thats easy to install and requires no to minimal maintenance. Remember this stuff is under water. Not easy to get to.
Because salt water is extremely harsh on machinery?
I just insist on nuclear. Reliable output all year round, vastly more efficient in land usage than other forms, completely safe and with practically zero environmental impact. The technology has advanced a fair bit since the 60's. Thorium fluoride reactors have no risk of catastrophic failure, no nuclear proliferation, and once we start working with fusion we will have a few thousand years of practically free energy for the whole planet.
Putting structures in the sea, or windmill farms covering vast fields really makes me worry about the environmental damage that does. The expense and waste down the line are also annoying.
I second this sentiment. Also with the work that Idaho National Lab is doing with modular reactors, we could reasonably start mass production within a decade. The upfront costs are in the millions, not billions, and last 40 years. When it runs low, pop it out for a new one. Game changing. It's not an American invention. However, those cutting edge technologies are being heavily funded out in Idaho.
I also like the idea of capturing the steam excess from reactors and replacing industrial heating applications or city service heating. Nothing wasted. Use it all.
I think thermal energy is more promising and not environmentally impactful.
Because under the ocean is a much more difficult environment to place a turbine compared to up in the air and basin based tidal power is pretty environmentally impactful. Need to focus our efforts on the low hanging fruit first.
Literally everyone in renewables it talking about tidal energy.
My guess is maintenance and longevity. We don’t have electric ships yet, so any tidal requires ships (Fossil fuel) for repairs. And salt water is incredibly corrosive, not to mention all the sea life that up has evolved over millions of years to stick to any surface.
When “the smart people” compare the maintenance needs along and power generation with off shore wind, (where the moving parts are above the water) my hunch is there there’s no comparison.
Also, speaking of that sea life…off shore wind farms have shown to crest new safe environments for fish. I doubt this would be the case for something that moves in the water.
As it stands power generation isnt a huge issue. We could meet our total consumption with just solar, wind and hydro.
The reason these are "not enough" is because we have to balance loads which PV solar and wind arent good at alone. The grid is designed to operate at 60hz (which is directly relates to voltage and current) >60hz and everything on the grid is destroyed (power surge), <60hz and you get brown outs. Your options here are to either up useage or reduce production when >60hz, and to reduce useage or up production. Steam turbines are really good at this because you can turn them on/off easily, add fuel or apply a brake for controls. Between wind ans PV solar, you pretty much only have access to a brake.
The solution is energy storage. concentrated solar power (CSP) uses mirrors to heat salt which then transfers the heat to a steam turbine. Batteries are very effective (a fresh lithium battery is probably the most efficient option) Pumped hydro is ~80% efficient.
Do you live near the ocean? Storms are incredibly powerful the natural environment is incredibly corrosive. Marine life like barnacles are always growing on the surfaces. There are far more cost effective solutions than putting a complex machine in saltwater.
It is interesting that you have given Nova and Orbital as two examples. Both have brilliant teams, have had devices in the water for years, and staff with real world experience.
Anyone interested in the field should absolutely look into their devices. A large part of their success has been a willingness to understand the operational environment and work with it.
Canada is one of the few countries to have begun to harness tidal energy; the country's only tidal station is located in Nova Scotia, in the Bay of Fundy. Our oceans are a vast source of energy that can be harnessed to produce different forms of usable energy including tidal and wave energy.
The Annapolis tidal barrage has been operating from 1984 2019
and the other company has filed for bankruptcy
'It is very unfortunate': Tidal power developer files for bankruptcy | CBC News
here are some links
FORCE
energy.novascotia.ca/sites/default/files/Tidal Energy Brochure Final April 2013.pdf
I believe the best ocean generating system would be to harvest ocean currents
Note: salt water and electricity don't combine very well
Because a study by Stanford university came to the conclusion that tidal energy is neither renewable nor unproblematic. https://cs.stanford.edu/people/zjl/pdf/tide0.pdf
Be it with a huge Asterisk that we are growing tidal energy according to our energy needs. But 1% of our energy need would halt the rotation of the earth in 1000 years.
Ok, this is technically not wrong, but it's also completely insane. They key part of this calculation is that it assumes humanities energy consumption will keep on growing at 2% for the next thousand years. At that point (assuming it is ever reached), humanities yearly energy expenditure would be approx 10^28 Joules per year, which pretty close to the output of a small star (the sun outputs about 10^26 Joules per second (per google), and it is not that small). If we're all still living on earth at that point, slowing down the rotation of the earth would be the least of our problems.
That article is what is technically known as a load of bollocks. There's no basis for the assumption of a 2% annual increase in energy usage. Just because it might be roughly correct for the last 50 years doesn't mean it will continue to increase like that.
The author of that article is assuming that in 1031 years when he says tidal power would have stopped the Earth's rotation, we'd be using well over 700 million times more energy than we did in 2013.
It doesn't sound very plausible.
Unfortunately, in this house we obey the laws of thermodynamics... So unless we figure out a way to shed copious amounts of low quality heat out of our atmosphere into space, producing and using more energy will lead to the planet heating up and killing us long before we slow it down... We are parasites on the surface, the earth will carry on long after we're gone.
This is under the assumption that our energy usage keeps increasing geometrically. Which probably would make the Earth a heated ball of humanity.
Just for comparison: with a current energy consumption of about 1,80E+17Wh per year and the rotational energy of the earth being 2,14E+29J, it would take about 330 million years for the earth's rotation to stop.
So we still have a wide margin for out energy consumption to increase, even IF we only use only tidal energy.
Rich people don't buy beachfront property to see a tide machine.
not sure who said it but it was someone at one of the energy companies...said if we had tidal done around a big portion of the UK, that would give us enough power for the UK and more for life...yes it will be expensive and mixed with other forms on top, but the cost alone would be not even half the price of building a nuclear power plant, plus we could start building it today, its 100% reliable cuz if waves stop, then we're long gone already...i think they said the cost of one nuclear power plant could give us 1.5 the amount of power we need with tidal. Its a no brainer really, for nuclear you its 15yrs minimum till its built, Climate can't wait that long and for something that its only going to cover a small overall percentage of power for the UK, where its tidal can power the entire country.
I've heard similar things about tidal energy, not just in the UK, and that's what got me thinking. If tidal energy can be so beneficial, yeah, it has its downsides right now, but if more people talked about it and more investments were made, we'd see more testing of technologies, more studies on its impact on marine life, and better chances to reduce the drawbacks and improve the tech... we need more clean energy for sure.
In the 60's big oil promoted solar and wind because it knew we didn't have the tech to make it work so it was a strawman compared to the reliability of oil.
I think this is close to the same thing. We don't hear about it because it works, and would disrupt the system, and before long, people are shooting nails out of electro rail guns because power is cheaper than bullets. Or that's what the big guys use as reasoning to prevent cheaply available power.