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The climate change debate continues.


Phil Perry

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Of all the renewables, wave power has been hardest to perfect, but it shines because:

- it’s greater during stormy weather, when solar is impeded

- it’s available 24/7

- it will help protect coastal properties against increasing storm damage caused by climate change. Win/win.

(Instead of spending a motsa on dumb concrete breakwalls, why not turn the destructive energy of waves into cheap, reliable electricity?)

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The King Island design is ingenious deriving its concept from blowholes which concentrates the energy from the wave and unlike other designs sits on the sea floor. A lot of other designs have failed when they end up being damaged by rough seas.

 

Tidal energy has been around for a long time using water turbines where there is a large tidal flow. The first one in the world was the Rance tidal power plant opened in 1966 in Brittany, France and at its peak generates 240 megawatts with an average of 57 megawatts.

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  • 2 weeks later...

The Chinese are right onto it, and you can even buy them off eBay.

 

https://www.ebay.com.au/itm/234424695729

 

I've often wondered about the feasibility of adding a large flywheel to the bottom of a vertical wind turbine, to keep the generator going when the wind had fallen away.

A flywheel in a sealed casing holding a vacuum, running on low friction ceramic bearings would keep spinning for at least 24 hrs.

Of course, a fair bit of wind energy would be required to spin it up to a reasonable speed, but after that, it would operate at a pretty stable rate - unless the wind dropped for a couple of days, which is rare. The wind rarely drops off for more than half a day.

 

Edited by onetrack
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10 hours ago, willedoo said:

I wonder how the 44 gallon drum version rates for efficiency compared to the aerodynamic tulip turbines.

 

FP_44-Drum(1).png

I always liked this simple design, but there’s got to be a reason for the big money going into large propellers. I presume they have greater efficiency at the large scale.

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They are very low efficiency. But that doesn't matter much to the DIY-er. It still makes free electricity and is relatively simple to make. A friend made a 44gallon one and it ran a car alternator to boost his off grid solar system. Apart from low efficiency, they suffer from being restricted to being close to the ground due to requiring substantial support structire. They need guy wires from the top. They do have the advantage of being quiet as well as cheap.

However, my neighbour replaced his with a small conventional propellor type atop a 50' mast, and that gave much better power.

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There were quite a few of them around years ago, but they have dropped out of favour. No doubt due to lack of ability and reliability. The old water windmills ran for years with little attention, but they never got used for electricity generation in any numbers.

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The big mining companies are really excited about the expansion of mining needed for renewables. Estimates of 8 to 10 times more dirt moved to satisfy lithium, copper, nickel etc demand. This is in the order of billions of tonnes of ore and overburden, to be mined all over the world but especially in Australia. Too bad I am retired! 

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The mining industry's job is to supply the minerals modern society needs.   This changes with progress and innovation.   It is clear that electrification is where we are going.   Mobile phones, laptops, household and grid sized batteries as well as EVs require different minerals from the past.  If big mining companies are excited by opportunities in the new technologies.  Of course as some newer mineral mining comes on board I guess other areas may decrease.     

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Recycling is going to be the major new industry of the future. Aluminium has a global recycling rate of 76%, steel is 60%, lead-acid batteries have up to a 90% recycle rate in developed countries. Copper recycle rate is around 95%, as it's also a precious metal.

Recycling of plastics and tyres are industries that have massive potential in the future, and the major aim of the Li-ion battery manufacturers is to get a recycling arrangement in place as part of the "circular manufacturing" system.

Metals such as Cadmium are a problem, and I only just recently found out, that Europe banned new Ni-Cad batteries in 2016, thus the reason for Ni-Cad batteries becoming scarcer. Cadmium is very toxic, unlike Lithium and most other metals in current use.

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Cadmium plating is a thing of the past It's very toxic. It used to be used a lot in aircraft engines but is now replaced with Zinc - Nickel alloy plating to a great extent.. IF you have anything on an aeroplane plated look up "Hydrogen  Embrittlement" and cover it by a post plating heat treatment..

 Beryllium Copper  is also carcinogenic.    Don't let it contact your skin,   (used on some valve seat inserts). Nev

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