Onshore wind farm subsidies to end.

[Suff]

Even more powerful is a reasonable river running off a weir and through a 10m tube at much greater volume with a larger screw, to fall 3m. So long as the water flows, it will provide the pressure needed. Also you can do this over and over again down the river without having to dam it.

There are weirs all down the river we live on and at every one there is a disused watermill. With modern technology, it's possible to have multiple Archimedes screw turbines at each weir.

The problem is we are revisiting the old mills with modern technology. So we've started on the windmills. How long will it take us to get to watermills again???

Talking about Hinckley Point C at a cost of £24bn for 3.2gw with a running cost of £92.50 per MWh does not really add up in the long run. Also it will take many years with no viable return whereas smaller high density clean energy projects could be up and running and generating revenue in as little as two years....

No wonder we get annoyed about it.

Even more annoying is that the government says that the cost at which electricity would have to be sold, for hydro, is £100 per mwh.

So let's take WM's model above and let's assume it runs 300 days a year at 16 hours a day at 4.5mwh each hour it runs.

That's 21,600 mwh per year or 2.16 gwh.

At £100 per mwh, the revenue in the first year is £2,16m Less the £600,000 it took to build and that's £1.56m revenue in the first year followed by £2.16m revenue in each following year without any running costs. Assuming we put them where the water flow is constant each year.

Food for thought.

[TheOstrich]

The earthmover manufacturer JCB have, at their Rocester (Staffs) training centre, an Archimedes screw turbine powering the complex. I've seen it in action (it's next to the car park they share with the soccer club) and it's quite hypnotic to watch!

http://news.bbc.co.uk/local/stoke/hi/pe ... 618475.stm

There was also something on the BBC local news tonight about using the River Severn flow through Shrewsbury to generate electricity

http://shrewsburyhydro.co.uk/

[Workingman]

Weir tables provide a quick and accurate means to determine water flow by measuring water depth flowing through a calibrated notch. The following table shows depth in inches and flow in cubic feet per second and in litres per second through a 90 degree, sharp edged V notch.

90 Degree V notch weir table.

Depth / inch 4 5 6 7 8 9 10 11 12 13 14 15 16
Flow / cfs 0.16 0.28 0.44 0.65 0.91 1.22 1.58 2.01 2.50 3.05 3.67 4.37 5.13
Flow / l/s 4.53 7.93 12.4 18.4 25.8 34.5 44.7 56.9 70.8 86.3 104 124 145

Notice the increase in flow versus depth. Make the weir depth 24 inch and the flow in l/s increases to 647l/s.

24" weirs exist all over the place and they produce quite a force.

If we only use them with a Reverse Archimedes Screw (RAS) that is a lot of electricity generated.
There are hundreds of weirs all over the UK doing the square root of sod all. Bring them back into operation.

[Suff]

There are hundreds of weirs all over the UK doing the square root of sod all. Bring them back into operation.

I wanted to get a measure of what this really meant in potential for electricity generation. So I tried to find out how many weirs there were in the UK. Did anyone have a register?

It was not easy, nobody seems to have a comprehensive list.

So, eventually, I found this document. The UK Hydrometric Register.

As far as I can work out, the vast majority of the surface water gauging stations are at weirs because they give flow and discharge values. I did the boring work of copying the tables into excel and stripping out the junk. What I got was not a surprise but was pretty large. The number was 2,629. Clearly they don't all flow with enough volume all year long. But the information is there, for someone who doesn't have enough to do in their life, to calculate out the best potential sites and their potential energy generation capacity.

Honestly it's got to be pretty large.

What's more, this kind of work uses local construction firms, local labour and "spreads the wealth" around in terms of clean energy.

Long gone is the time that we had to have the factory connected to the wheel that was turned by the water. Today, power generated by hydro in the north of Scotland can be used at Land's end.

Government, head up anus thinking. Or, more likely. Government lobbied to go for centralised single power solutions which lock the people into high energy prices...

There is even a Good Practice guide for working on, removing or creating Weirs...

[Workingman]

Thanks for the links, Suff, I will include them in my e-mail to my local MP. For me our waterways are our most underused resource.

Take the river Wharfe. Its head is ~300m and its average depth between high and low levels is ~1m. Near here there a three weirs and two goits over a distance of about 6km. In their heyday they were used to power two woollen mills, one paper mill and numerous other works such as forges. Think of the power needed to work hundreds of cast iron and hardwood looms given the inherent inefficiency of 19thC waterwheels. Think how much power modern technology could take out.

Weirs, goits, sluices and small hydro, useful for generating electricity, are also necessary for river management.... we could probably do with more of them.