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Tidal power - sense at last!

PostPosted: 14 Jan 2013, 10:15
by Workingman
A report by the Royal Society indicates that the UK could get 20%, or more, of its electrical energy from small(er) scale tidal projects. It argues that they are more efficient than wind - no surprises there, then - and are less environmentally damaging than the proposed huge Severn barrage. Thank God for engineers!

An ample sufficiency of smaller scale alternative energy resources is what some of us have be arguing for for donkey's years. It appears that we are now being listened to. Small to medium sized barrages are known to work, as are tidal turbines, and we have plenty of sites available.

The snag? Finance. It's down to money, not, as one would suspect, energy security. The pay back is on time scales that capitalists cannot work to, but then so are those for nuclear, wind, coal and gas.... but those are proven technologies, aren't they?

Re: Tidal power - sense at last!

PostPosted: 14 Jan 2013, 11:32
by Aggers
Employing tidal energy certainly sounds a more sensible way of dealing with the matter.

I do, however, wonder whether tidal turbines would have a reasonable lifetime in such inhospitable environments.

The more sensible approach might be to curtail the enormous waste of elctrical power that currently takes place.

Re: Tidal power - sense at last!

PostPosted: 14 Jan 2013, 12:09
by cruiser2
When I was working,I went to visit a client in North Wales. He had a small hydro generator for his house which had been installed many years ago. He even got paid as he would generate more elecrticity than he could use. This was in the early 1970's well before renewable energy was all the rage.

Re: Tidal power - sense at last!

PostPosted: 14 Jan 2013, 12:25
by Workingman
Aggers wrote:I do, however, wonder whether tidal turbines would have a reasonable lifetime in such inhospitable environments.

Aggers, for a time I worked for a pump refurbishing company. We often serviced pumps installed in the 1920s and they were still operating. A couple of problems applied: Cavitation. It would create pits behind the leading edge causing erratic flows and decreased efficiency. Build up of deposits on the operating surfaces of the casings and the impellers, again, decreasing efficiency.

These are now largely overcome with better design and coatings. Remember we have ships of great age still operating in the same hostile conditions, but in a slightly different way.

Re: Tidal power - sense at last!

PostPosted: 14 Jan 2013, 12:45
by cromwell
The thing with the tide is - you know it's going to be there. There are problems witht the turbines in the Hoover dam getting crusted up with some kind of aquatic creature, but they deal with it.
We should have been using water driven turbines 40 years since. (Actually we were doing long ago but just seemed to stop!)

Re: Tidal power - sense at last!

PostPosted: 14 Jan 2013, 13:19
by Workingman
cromwell wrote:We should have been using water driven turbines 40 years since. (Actually we were doing long ago but just seemed to stop!)

A rather large Bumble in my particular bonnet, and as Cruiser points out, even at the very small scale you can get out a lot more than you put in.

Re: Tidal power - sense at last!

PostPosted: 14 Jan 2013, 20:22
by Suff
Aggers wrote:The more sensible approach might be to curtail the enormous waste of elctrical power that currently takes place.


One man's waste is another man's meat and potatoes....

It is simply not possible to maintain our level of society, technology and freedoms at the same time as trying to reduce our energy dependency. Also it's a vote loser. So don't expect anyone but the totally unrealistic greens to back that one.

Also remember that our "Energy budget" is not just power but also fuel. Fuel makes up way, way more of the "energy" than we generate, although fuel also is part of the energy generation infrastructure.

Also remember that if we are going to get rid of CO2 producing vehicles, then we will need MORE power, not less. Much, Much, Much MORE power. Probably 3 times what we generate today. Not just for electric vehicles but also for hydrogen and other hybrid fuels, all of which take energy to manufacture. Note, nobody has, to date, had the slightest wet dream about an electric powered truck. Well not one that runs on batteries that is.

So Hydrogen and Ethanol are both viable for trucks but we need to stop wasting that energy inside the engine. Note, the standard IC engine is 20% thermally efficient and about 300% mechanically IN-efficient. We also need to fix these things too.

So we need tidal, we need river, we need solar and we desparately need HDR geothermal. Currently on the table is Nuclear. Of which we'd need another 80 power plants around the UK at several billion per power plane and a decade or two to build. Plus that level of massive Nuclear power station increase would make Uranium about as scarce as Copper is becoming and the price of that energy would go through the roof.

The most important thing to watch for, in all of this, is not the words spoken. It is the actions taken.

Re: Tidal power - sense at last!

PostPosted: 15 Jan 2013, 11:11
by Workingman
Suff wrote:The most important thing to watch for, in all of this, is not the words spoken. It is the actions taken.


And those actions, so far, have been to tweak the edges, prevaricate, and then make the wrong decisions (wind power). Only a very few of those with influence have been prepared to look outside the box. They have bought in, hook,line and sinker, to the grand schemes, the visible schemes, and forgotten that if you look after the pennies.... Yes, there are still savings to be made in energy efficiency, but most of the work has already been done. Nobody should be fooled into thinking that it is the panacea.