A feasibility study to make carbon free based load power from the tides in enclosed waters (harbours, estuaries, etc)

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A Feasibility Study To MakeCarbon Free Base Load PowerFrom The Tides In Enclosed Waters(Harbours, Estuaries, etc)executive summary

1. We appear to have invested untold millions of dollars on solar and wind, yet the total amount of electricity generated, while helpful, is insignificant when looked at from a national point of view. We need to think bigger.

2. We need a way to make huge amounts of power from one or two plants that more than meets our needs now and way into the future.

3. After Chernobyl and what happened in Japan plus the accident at Four Mile Island in USA we probably don’t want nuclear at any price.

4. The only way to make carbon free electricity in huge quantities is harnessing the tides and I believe I know a way to do it.

5. Here in the north of Australia we have the most incredible opportunity to do just that because we are blessed with huge tides.

6. There is increasing urgency to solve the climate change crisis and the youth of today are leading that charge.

7. I believe we need to think BIG, invest the billions and start making real power in sufficient quantities to cater for our every need and even export some as well. Read on to see how.

Article

Let me introduce myself. My name is J. Duncan McNeill and I live in Darwin. I am well known as an inventor with a way of thinking that allows me to clear my mind of all existing thinking and start again with a ‘clean slate’. Thus I can bring refreshing new ideas to the table.

I call myself a product design engineer though I have no formal training in that field but all my product designs are innovative and unique and all work extremely well. Check me out at www.beat-the-vandals.com where you can see my latest product ready for someone to take up.

For 20 years now I have been advocating using the power of the tides to generate carbon free electricity in our harbour. A few years ago I visited Homer on the south west coast of Alaska. On a wall in the museum there was a map of the local area with points of interest noted, but the thing that got me really excited was a fiord just south of Homer and the note there said ‘If we could harness all the power of the tides flowing in and out, there would be enough power for 10,000,000 homes’. Of course I have no means of checking how accurate that is, but even if the real figure is half that, it is still a very large amount of power. My immediate thought was, ‘We probably don’t have that many homes in all of Australia’.

We need to ask the question:

Why Tidal?

There are several reasons. Solar doesn’t make any power at night or when it is cloudy (and what do we do with millions of dead solar panels when their 20 year life span is up?). Wind doesn’t make any power when there is no wind (and wind turbines kill birds). Wave power doesn’t make power when the sea is calm. Not only does that mean there are periods of no electricity production, but all three are totally unpredictable and unreliable. Also, we have invested millions of dollars on those and we still have huge power stations spewing millions of tons of carbon into the environment. We must find a way to do it better.

Sure, tidal doesn’t make power between tides, but at least it is 100% reliable and totally predictable. We can know in advance exactly how much power will be made on August 27th 2053 or any other future date you care to name.

Another reason is that water is 832 times denser than air, so an 8 knot current has the same energy as a 380 kilometre per hour wind (source: Google/ Wikipedia). It is easy to harness an 8 knot current but difficult or impossible to harness a 380 KPH wind – not to mention that an 8 knot current is a daily event while a 380 k wind is very rare.

South Korea has dappled in solar, wind, tidal one way and tidal two ways and done a costing on the four ways. Power production costs per 1KW is 400 Won for solar, 200 Won for wind, 90 Won for tidal one way and 45 Won for tidal two way.

Tidal one way is when the tide is allowed unrestricted entry to an estuary or harbour with electricity generation only when the water flows out, or power is made on entry but the water flows out freely. Two way is when power is made both ways. My thoughts for this project is two way.

South Korea has the worlds largest tidal power station producing 5.5 billion kilowatt/hours annually. This is a one way station making power when the tide comes in only.

We are blessed with huge tides here in Darwin, with a huge harbour which is what got me thinking about this amazing resource. Upon doing further research, I have found that the further west you go from Darwin the tides get bigger; indeed, Derby has tidal differences of over ten metres (spring) to a low of seven metres (neap). The tides subside as you go further around the coast from there.

After Darwin, the next obvious site is Cambridge Gulf where the tidal flows vary from 7 metres to 9 metres. The port of Wyndham in that gulf (population 900 in 2018) services the cattle and mining industries.

As near as I can tell, (looking at a map in an atlas) the estuary appears to be between two and three times the size of Darwin and there is approximately a seven kilometre entrance, then Lacrosse Island (right in the middle of the overall opening) and then another seven kilometres that would need to be dammed.

A huge advantage with Cambridge Gulf is the low population in that area combined with the fact that the power plant would be “out of sight, out of mind” from the town means there would hopefully be minimum opposition, objections, etc.

The amount of electricity that could be generated if we harnessed all that power boggles the imagination – not only supplying all of our needs (including transport) but we could export to much of south east Asia as well.

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How To Make Base Load Power From Tidal Generation

By now you are thinking that’s fine but you mentioned base power – how can you do that when there is no power through the tide changes?

Easy:

When you are making lots of power, you use some of it to perform electrolysis on water to separate it into hydrogen and oxygen. You release the oxygen (or bottle it) and keep the hydrogen.

Hydrogen can be converted back to electricity in two ways: directly through a fuel cell; or you can burn it pollution free where the only product of combustion is clean pure water. This burning can take place in existing power stations that currently run on gas or coal which I imagine would only take minor modifications.

Further to this, hydrogen being the lightest gas of all, a huge quantity of it can be moved through a relatively small pipe. Indeed, our existing gas pipelines could be used to send hydrogen down south. What’s more, there are no losses in sending it long distances as there is now transmitting electricity overland. A hundred units of power leaving the north coast will still be 100 units in Sydney or Melbourne.

(I believe California now have hydrogen available by bowser and Honda have made a car that can travel 370 miles on one fill).

How Much Power Can We Make?

Unfortunately I am not the right sort of engineer to calculate that and I have been unable to find someone who can, but quite clearly the potential to make enormous amounts of electricity is there. If we had the will, it could be done but we need to THINK BIG and be bold and just do it! Dare to be different and show the world.

Are Turbines The Best Option?

Short answer – no.

I am not convinced that turbines are the way to go. Below you can see images of two different types of turbines, (one in a tunnel, one in open water) which they claim to be ‘fish friendly’, but I don’t really believe that. While smaller fish might slip through unharmed, a large fish (shark? whale?) may well get stuck and drown.

But I have another major reservation about turbines. You can clearly see that if you were to lock the turbine in its tunnel so it couldn’t revolve, the water can still get past it quite easily. Sure, the water would have to do a little chicane to get past but there really would be very little restriction or resistance. Therefore it is obvious that a turbine can only harness a very small amount of the power – maybe less than 10%? (That is a guess on my part, but probably pretty close).

As an inventor, I have a better idea. What I can see is a row of paddle wheels side by side that stretch from shore to shore; they would be very similar to that of a stern wheeler river boat. They would need to be at least twice the diameter of the expected tide with the axle above the high tide mark to cope with the biggest tides where the water was shallow, but for maximum efficiency the engineers who do the final design may make them much larger in deeper water. They would sit in channels exactly the same width as the paddles and the bottom of the channels would have the same curve as the circumference of the wheel.

Now it can be clearly seen that if the wheel was locked unable to turn, no water could get past it. This now means that every little bit of energy that is available can be harvested, whereas a turbine could only gather that tiny little bit mentioned earlier. This is very similar in principle to the undershot water wheel of two centuries ago.

Below is a side view of how my paddle wheels might look.

It is plainly obvious that this arrangement would be a sure fire fish killer. Where the tip of the blades first touches the curve on the floor of the channel would cut a fish in half if it happened to be in the wrong spot, so we need a fish strainer. You can’t just have a net of the right mesh across the opening as a fish could get caught against it and the pressure of the current may hold it so it can’t escape until it dies. Also a net would restrict water flow too much. No, we need a design that will allow free entry of water but fish can just turn and swim away.

My suggested design is a tapered cone, though it could just as easily be three or four sided, with thousands of small holes (maybe 10 to 15 mls?) and if a fish comes too close it can swim with the current and escape at the thick end of the cone.

Fish Strainer

These could be painted in anti-foul paint and would need to be cleaned regularly. It would also be very feasible to lift them out of the water at all times except when actually needed. Thus they would spend more time out of the water than in it, which would reduce maintenance. Ditto the paddle wheels.

There is another possibility. There could be a row of fingers in front of the paddle wheels set permanently into the concrete. When a fish came past the fingers would lift it above the danger spot and it could swim on through unharmed.

I imagine the cost to make a dam containing turbines would be about the same as a dam containing paddle wheels. So to me it would be a disaster to use turbines which will only make a pathetic amount of power compared to what the paddle wheels could and would do.

Summary of paddle wheel advantages

1. Paddle wheels will never hurt a fish.

2. Wheels and strainers can be lifted out of the water between tides to allow free access for fish and boats.

3. All electrics and electronics are on dry land for easy servicing and repair.

4. Wheels and strainers can be cleaned/ serviced while out of the water between tides.

5. Paddle wheels can make as much power as we want - enough for all our needs including transport as well as export opportunities.

6. Turbines could never do that unless we had a million of them, plus they are hard to service being underwater and I am not satisfied they won’t hurt fish.

7. If a turbine ingested a fishing net just imagine the mess!

With my long association in product design, I just know this will work. I only hope that I have convinced you.

Every product I have developed I have gone right away from tradition and tried to produce things that are unique and innovative, and they have all worked. I mention this to encourage you to accept that a new way is better, and this way of harnessing the tides is no different.

I am sure you can now see that the potential is simply staggering, but now the big question: Do we want to do it? Do we have the will to do it? Do we dare? I say yes, we can’t afford not to.

This is a real way of making huge amounts of base load electricity carbon free at minimum cost and is a major step towards helping to save the planet.

If we could make this work, it would show the world and the idea could be copied everywhere!

Can we at least have a qualified engineer do a feasibility study and a costing on this?

Idea by J. Duncan McNeill, PO Box 1255, Darwin NT 0801. duncinvent@gmail.com0437 383 070.

Footnote: If we did proceed with this and it is all proven, why not do it in King Sound as well? That is more than huge! Instead of ships leaving our shores carrying gas as now, they could carry frozen hydrogen. Think of the export dollars from that?