Potential for tidal power generation? Sailors thoughts.

[NormanS]

They are only "economic" because of the subsidy given to build them and the higher price paid for their output - all courtesy of our inflated energy bills. Doing the calculations that way shows a "profit" for the operator. Also of course, no charge for the impact on the environment nor of the disposal cost when policy or technological changes in the future require them to be removed.

I might live long enough for wind energy to be shown as one of the worst policy decisions of all time. Not that I am biased of course!

If you're going to mention end of use disposal costs, what about nuclear?

 

[chrishscorp]

If you're going to mention end of use disposal costs, what about nuclear?

Latest cost estimate for cleaning up the Fukishima site ( ok worst case clean up ) 8 Trillion Yen

Not a fan of nuclear, clean up costs are unknown for our sites in the UK and frankly who the h#ll wants the Chinese building a new nuke power station over here ?

 

[Tranona]

If you're going to mention end of use disposal costs, what about nuclear?

Was not making a comparison. Nuclear is also heavily subsidised, although we avoid most of it by importing electricity from French nuclear generators.

On a straight current cost of production basis only fossil fuels deliver electricity at less than the price we are charged. Everything else is distorted by subsidies and exclusion of disposal costs. As those, and environmental costs are largely unknown it is impossible to make any direct comparison of overall cost, hence the widely different figures bandied around depending on who produces them and what conclusion they want to promote.

 

[A1Sailor]

On a straight current cost

AC or DC?

 

[NormanS]

Was not making a comparison. Nuclear is also heavily subsidised, although we avoid most of it by importing electricity from French nuclear generators.

On a straight current cost of production basis only fossil fuels deliver electricity at less than the price we are charged. Everything else is distorted by subsidies and exclusion of disposal costs. As those, and environmental costs are largely unknown it is impossible to make any direct comparison of overall cost, hence the widely different figures bandied around depending on who produces them and what conclusion they want to promote.

I do know that Scottish hydro power is only a small producer in the Scottish market, and tiny in the UK, but since most of the construction costs were written off decades ago, and there is no fuel cost, it must produce the cheapest power here.

 

[A1Sailor]

I do know that Scottish hydro power is only a small producer in the Scottish market, and tiny in the UK, but since most of the construction costs were written off decades ago, and there is no fuel cost, it must produce the cheapest power here.

A small producer that generates nearly 20% of Scotland's electricity...
http://www.ybw.com/forums/showthread.php?492417-Scotland-s-lecky

 

[NormanS]

A small producer that generates nearly 20% of Scotland's electricity...
http://www.ybw.com/forums/showthread.php?492417-Scotland-s-lecky

Yes, and 20% still qualifies in my book as small. However, I'm sure that hydro production is now increasing, with more and more small scale schemes being built, which can only be a good thing. (Unless the rain stops, which would also be a good thing).

 

[zoidberg]

More than 50 years ago, one of my mates was employed designing/installing small hydro schemes around the Scottish regions, for a UK Major company large in power infrastructure. I'm willing to believe that efficiencies have improved this past half-century.

He told me then that every village, hamlet and small town could be self-sufficient for electricity, if they invested in the kit.

I suspect there's our problem...

 

[Quandary]

In my former life I had a few commissions for projects where there had been century old hydro schemes, to look green communities and charities always wanted to restore them so we did quite a few, rebuilding weirs and clearing laydes.
Interesting thing was that most of the old turbines, some with hardwood bearings, still ran and were very nearly as efficient as new French or Danish ones when paired with a modern generator, the limiting thing was simply the head and volume of water. We did a thing where the overflow spillway outfall was meticulously levelled so that the falling water looked like a shining sheet of glass.
Great fun, cheap to do, but an entertaining loss leader for our Practice, particularly when you got hands on and were wading about in rivers.

 

[johnalison]

Being ignorant of what laydes are, I did a bit of googling. On the whole it was unproductive, though the Urban Dictionary gives an interesting definition, so I am none the wiser. I presume that they are water channels of some kind?

 

[penberth3]

Being ignorant of what laydes are, I did a bit of googling. On the whole it was unproductive, though the Urban Dictionary gives an interesting definition, so I am none the wiser. I presume that they are water channels of some kind?

It's the Scottish version of Leat. Inlet channel to a mill, water wheel, turbine etc.

 

[NormanS]

Being ignorant of what laydes are, I did a bit of googling. On the whole it was unproductive, though the Urban Dictionary gives an interesting definition, so I am none the wiser. I presume that they are water channels of some kind?

I think they are more often referred to as "lades".

 

[A1Sailor]

Being ignorant of what laydes are, I did a bit of googling. On the whole it was unproductive, though the Urban Dictionary gives an interesting definition, so I am none the wiser. I presume that they are water channels of some kind?

Also spelt "Lade"

Scottish
A channel constructed to carry the swift current of water that drives a mill wheel.
‘a lade from off the Tarland Burn’
https://en.oxforddictionaries.com/definition/lade

Edit:
I used to live in Ladeside Close. It is quite a common name - Ladeside Primary School, for example. www.ladeside.falkirk.sch.uk

 

[Sybarite]

These are both cheaper and more effective that the static Strangford Lough type generator :

https://www.theguardian.com/environm...turbine-scheme

Read more at http://www.ybw.com/forums/showthread.php?476925-Tidal-power-moves-forward#qDExvoZ6lOxvmvx3.99

 

[interloper]

Regarding tidal power generation, one disconcerting aspect is that the energy is being extracted from the rotational kinetic energy of the earth-moon system. Yeah, I know it's an infinitesimal amount, but idea of deliberately slowing the earth's rotation is a bit unsettling.

Regarding energy storage, how many know that the world's largest battery is located in Virginia? It's the Bath County Pumped Storage Facility.

 

[guernseyman]

I seem to recall, but may be mistaken, that there was once a small tide mill of the latter kind on the Rance itself.

There were several on the Rance, and many others in North and South Brittany. Two of the most obvious are in Ploumanac'h, one of which is open as museum on the subject. There was also a failed large one at L'Aberwrac'h.

 

[Hydrozoan]

There were several on the Rance, and many others in North and South Brittany. Two of the most obvious are in Ploumanac'h, one of which is open as museum on the subject. There was also a failed large one at L'Aberwrac'h.

Yes thanks, a quick search showed at least 3 on the Rance (see #24). What I wonder was the cause of failure at L'Aberwrac'h?

 

[sgr143]

For some basic physics and data on tidal power for the UK, I can recommend chapters 14 and G in David MacKay's excellent book "Sustainable Energy – without the hot air". Actually, I recommend the whole book, which does a detailed but very readable quantitative analysis, based on real data and proper science, of what energy the UK uses (and for what) and where is does and could come from. MacKay knows his stuff - he was a Professor of Engineering at Cambridge, and was Chief Scientific Adviser to DECC. He was a firm promoter of energy conservation and sustainable "green" energy, but insisted on doing the maths properly, rather than just hand-waving.
https://en.wikipedia.org/wiki/David_J._C._MacKay

You can get the style of the man and the way he works here;
https://www.ted.com/talks/david_mackay_a_reality_check_on_renewables#t-1095796
Things have moved on a bit since he gave this talk, in the directions he was pointing, too, but the overall conclusions still stand.

The conclusion is that tidal power could make a significant, but not game-changing, contribution to the UK energy supply: "Totting everything up, the barrage, the lagoons, and the tidal stream farms could deliver something like 11 kWh/d per person" - out of a total likely energy need of 195 kWh per day per person.

You can buy the book, but the whole thing is also free to read and download:
http://www.withouthotair.com/Contents.html

 

[Biggles Wader]

For some basic physics and data on tidal power for the UK, I can recommend chapters 12 and F in David MacKay's excellent book "Sustainable Energy – without the hot air". Actually, I recommend the whole book, which does a detailed but very readable quantitative analysis, based on real data and proper science, of what energy the UK uses (and for what) and where is does and could come from. MacKay knows his stuff - he was a Professor of Engineering at Cambridge, and was Chief Scientific Adviser to DECC. He was a firm promoter of energy conservation and sustainable "green" energy, but insisted on doing the maths properly, rather than just hand-waving.
https://en.wikipedia.org/wiki/David_J._C._MacKay

The conclusion is that tidal power could make a significant, but not game-changing, contribution to the UK energy supply: "Totting everything up, the barrage, the lagoons, and the tidal stream farms could deliver something like 11 kWh/d per person" - out of a total likely energy need of 195 kWh per day per person.

You can buy the book, but the whole thing is also free to read and download:
http://www.withouthotair.com/Contents.html

See #12
Rule 1----Read the thread before posting

 

[sgr143]

Apologies - I did try to check the thread through before writing my post, but must have skipped a block of posts.... mea culpa.

On the other hand, the message is worth repeating! (Especially since post #12 seems to have been completely ignored by the continuing thread...)

S