http://news.bbc.co.uk/1/hi/business/8387449.stm

Very interesting Do you think if this is a growing trend it may have an effect on caving? Or maybe land access issues?

Daz :-\

good stuff 

Cant see there being a problem with caving. The E.A. are very hot on run of river schemes and depleted stretches of river. All sites will have to have had an abstraction license agreed with the EA in the first place.

If anyone wants me to come and do a feasibility on their location  . 

Hmm - wonder if speedwell have thought about a turbine on the bung, or the bottom of those pipes in JH :-\

Reminds me of "I Bought a Mountain" by Thomas Firbank. It tells the story of a Canadian who bought the farm down the road from Plas y Brenin in Capel Curig in North Wales in the 1930's.

He created leats to divert water to a small hydro-electric scheme he had set up, among other things.

And he didn't have the incentive of selling excess electric power to the National Grid at premium rates which is certailnly an incentive for many recent similar "eco" schemes.

You would get a good bit of power from fell beck. 9 bar pressure and a sizeable stream. Diccan could be good also. Thinking about it there are dozens of good potential cave sites in terms of generating capacity. Can imagine the outrage caused if any plans are submitted for them. Out of interest, anyone know the average flow rate of fell beck or long churns?

We only play at interfering with caves in the name of hydroelectricity here in Blighty. Go and have a look at the EDF Tunnel leading into the Salle Verna in the PSM.

As far as Fell Beck is concerned the lowest flow is probably something like 3 litres per second (this being an estimate from seeing it many many times in ultra drought - it's not an actual measurement). In absolute mega flood it wouldn't surprise me if it was approaching a cumec.

Anyway, you don't need a stream. You can do it with just a pool. If you have a series of hydraulic ram pumps ("hydrams") conveying water up to a tank on a hill you can then release the water down a big pipe with a generator at the bottom and you can have free sparks.

Hydraulic ram pumps ("hydrams") use 6 gallons of water to pump up one gallon of water.  Not very efficient

If you look properly at the economics and engineering of this exercise, you discover that (1) Welsh hill farmers live the dark and don't boil their kettles very often; (2) for it to be viable at all there needs to be a grid connection very nearby; (3) the economics only stack up as an alternative to sticking the money in the bank or building society at current interest rates for saving and borrowing, they certainly don't stack up as a viable long term business proposition; and (4) you need a bloody big stream to make it work at all.

Nick.

Funnily enough I've just been to Dinorwig. They manage to do this, buty they have to pump all teh water back to the top of the hill every night.

One assumes that Graham knows about 'peak lopping' i.e. matching demand spikes on the Grid which is were Dinorwig comes into its own (and the fact that you cant just turn a normal powerstation off at night, hence the 'spare' electricity on the grid at night which is when they pump it back up to the top.
"Synchronised and spinning-in-air emergency load pick-up rate from standby  0 to 1,320 MW in 12 seconds"


As for nicks assumption that you need a 'bloody big stream' to make it all work, that is not the case at all. Head is where its at.

"he economics only stack up as an alternative to sticking the money in the bank or building society at current interest rates for saving and borrowing, they certainly don't stack up as a viable long term business proposition"
Thats bollocks too, if you have a reasonable site, then payback can be relatively quick (5 to 8 years) after than - its just money in the bank with the Renewable Obligation Certificates you'll be earning, you can make a tidy sum selling them to the energy companies. They can have a very long lifespan too. Many of the Major hydro schemes where built over a 100 years ago (OK - so most have had a recent refit of new turbines/valves)
The 'Feed In Tariffs' that the Gov will probably introduce soon will help things along too.

He's right about grid connection though. It costs thousands to put lines in (think 3000 up front then an additional 1000 per pole as a rule of thumb).

It can still stack up though. There are tones of micro hydro schemes cropping up all over, especially in Wales at the moment.

Sam,

Head equals pressure. How does that turn into power without volume?

Nick.

A combination of head and flow rate is what determines the power obtained. Turn the thing on its head, and think about the power required to raise water to a higher level at a particular rate.

This is something I am heavily involved in here in the Black Mountains. We have identified many good sites but are only really looking at 3.5 KW max due to limitations placed on us by the electricity infrastructure (single phase) To generate 3.5 KW reliably you need about 10 l/sec flow with a 300 foot head which is not that difficult to achieve on many of the streams round here for more than 6 months of the year. With own labour and machinery for trenching and building it should be feasible to install such a scheme for around the 10K mark or less. With next years feed-in tariffs this represents a pay-back of around 3-4 years so makes very good economic sense. 

Hope to have a go at my own scheme this coming spring.

How optimistic are your figures? What happens if (for instance) you have to pay someone else to do the installation and maintenance work, you only get 4 months of viable rain and and the tariff/tax breaks evaporate?

I'm not trying to pick holes, I'm genuinely interested to know. Unfortunately, my farmland is flat so it's never going to work for me!

Nick.

I'm hearing of loads of projects on farm land here in south Wales, there is a particular one running in Llangatock that is being developed as a comunity project. I also hear that you will get paid for the powder you consume yourself and not just for the powder you sell back to the grid. Could be a nice way of finacing your club cottage. This is all about our government meeting European targets, it'll be cheaper to pay people for the power they use if they generate it themselves, than to pay the fines imposed by the European energy police!

Dan y ogof show caves have been using hydo for many years, they stand to make a few quid I'd say.

nickwilliams said:

How optimistic are your figures? What happens if (for instance) you have to pay someone else to do the installation and maintenance work, you only get 4 months of viable rain and and the tariff/tax breaks evaporate?

I'm not trying to pick holes, I'm genuinely interested to know. Unfortunately, my farmland is flat so it's never going to work for me!

Nick.

Click to expand...

Figures are over pessimistic. Paying for full install would probably double the costs though (so halving the payback time). Chosen with care your stream should produce electricity all year round but at a reduced rate in summer. Figures thus based on yearly average.

There are 2 elements to the payment received. Frst is the feed in tariff, which is less than you pay for buying electric from the big providers. Therefore it is sensible to use all your own produced electric to meet your own needs as far as possible and only buy in what is needed to cover peak periods. At night and when consumption is low you sell excess electric to the grid. The second element of payment is in the form of ROCS Renewable Obligation Certificates) which the government pay as you are helping to meet their CO2 targets. This is paid on all energy produced regardless of whether you use it or sell it ot the grid. The amount paid varies according to the type of renewable energy. Wind pays better than hydro and I think Solar PV pys better again. Apropo Solar PV. This is supposed to be going to be pushed (subsidised) for all in the near future so everyone should be able to get on the renewable energy bandwagon, not just those with streams

I hear that thanks to better than expected longevity, solar panels have now reached the point, in southern Europe at least, where they are generating sufficient power to cover the cost of the installation, that is, they cost no more, possibly even less, than the cost of buying the same power from a large generating company. The guess was that longevity and improvements in efficiency would mean that the same state could be reached in more northern latitudes (i.e. round Nick's way) in the next 10-15 years.

I'm sorry I cannot find the link, but the significant point was that the figures were calculated without using any subsidies.

One thing that could effect caving areas is that of stream diversion, if this is going to pay well, then who wouldn't be tempted to divert a few small streams into one large stream. This could intern lead to upland drainage being altered, with hydro plant owners pulling water off upland areas to their own land. Water wars!! we'll soon see land owners filling in their neighbour's drainage ditches and claiming the water as theirs. Water management groups would need to be set up to keep everyone in check, sound familiar?

graham said:

I hear that thanks to better than expected longevity, solar panels have now reached the point, in southern Europe at least, where they are generating sufficient power to cover the cost of the installation, that is, they cost no more, possibly even less, than the cost of buying the same power from a large generating company. The guess was that longevity and improvements in efficiency would mean that the same state could be reached in more northern latitudes (i.e. round Nick's way) in the next 10-15 years.

I'm sorry I cannot find the link, but the significant point was that the figures were calculated without using any subsidies.

Click to expand...

Can you recall, is this solar panels to provide electricity, rather than solar panel to heat  water (which are very common in tourist areas of the Med)

kay said:

graham said:

I hear that thanks to better than expected longevity, solar panels have now reached the point, in southern Europe at least, where they are generating sufficient power to cover the cost of the installation, that is, they cost no more, possibly even less, than the cost of buying the same power from a large generating company. The guess was that longevity and improvements in efficiency would mean that the same state could be reached in more northern latitudes (i.e. round Nick's way) in the next 10-15 years.

I'm sorry I cannot find the link, but the significant point was that the figures were calculated without using any subsidies.

Click to expand...

Can you recall, is this solar panels to provide electricity, rather than solar panel to heat  water (which are very common in tourist areas of the Med)

Click to expand...

Bloody annoying that I can't find the link. it was talking specifically about the economics of running Pv panels. So generating electrickery, yes.

nickwilliams said:

Sam,

Head equals pressure. How does that turn into power without volume?

Nick.

Click to expand...

well of course you do need some flow -

P = Qgh

power = Mass flow rate * gravity * dynamic head (i.e. after friction losses etc).

so a high head negates the need for a large flow. Obviously high head & high flow means you laughing.

There are little pelton wheels that will run on a very low flow, so long as the pressure (i.e. head) is great enough.