Yes, the 24 kWh per day is for the prototype at St. Catherine's and if that's what's in the photo the head appears to be a lot more than 20 cm. And how do they get "at least 24 kilowatt hours of sustainable green energy in a day" from something that "produces one to two kilowatts of power." The invisible perpetual motion booster, presumably.
I noticed that too, and it's bollo. Average consumption, where electricity is not used for extensive space heating is around 3,300 kWh per year, i.e. about 9 units a day.
Lancaster University's renewable energy research group also seem to be interested in low-head hydro and
the wheel rotates, but the Beck Mickle Hydro generator contains the water for the full drop of the device, converting around 70 per cent of the energy into electricity.
The picture in the link shows that the drop is fully utilised by converting the drop from a radius of a curve to the full 9 yards with a caterpillar type conveyor."
There has to be a system loss as the engineering principle is lost energy in a vehicle. Is that not so?
|Dave Liquorice wrote: | |> Read the articles carefully. With 20cm head you get a "useful amont of |> power" not the 24kWHr's/day that they also mention. | |Yes, the 24 kWh per day is for the prototype at St. Catherine's and if |that's what's in the photo the head appears to be a lot more than 20 cm. | And how do they get "at least 24 kilowatt hours of sustainable green |energy in a day" from something that "produces one to two kilowatts of |power." The invisible perpetual motion booster, presumably. | |> What I do question is the demand of a "household" 28kWHr's/day? | |I noticed that too, and it's bollo. Average consumption, where |electricity is not used for extensive space heating is around 3,300 kWh |per year, i.e. about 9 units a day. | |Lancaster University's renewable energy research group also seem to be |interested in low-head hydro and |
formatting link
|is quite interesting.
Howsham Mill which won the North of England heats of BBCs Restoration, but failed to win the National Competition is installing a reversed Archimedean Screw for electricity generation. This also looks for low head high volume, fish friendly, applications.
Mains water has a minimum pressure of about 4 or 5 Bar IIRC, or approx
130 to 160 feet. But sheer pressure is not the whole story with a water turbine. You can get the same power with high flow/low pressure or low flow/high pressure.
er, 1kW for 24hrs is 24kWHr... 2kW for 24hrs is 48kWHr. So provided the average output is > 1kW you get the "at least" 24kWHrs.
hum, 375W average base load. We generally have 200W of lighting (no tungsten) for 18hrs day... I'd love to get ours down to that level but I can't see it happening. No space heating via electric included in our
21/22 units/day, space heat comes from oil.
Trouble is with a low head you need a hefty flow, fine if you have a reasonable sized river and weir though.
I got one from you. I rather believe low rates of replies to my posts are more likely due to my lack of empathy for idiots. And an inability to refrain from showing contempt where a more mature nature would tolerate other people who mean nothing to me.
As it happens I couldn't think of the right terminology since the concept of reciprocating engines as direct road thingummy is not my forte. Perhaps you would be so good as to explain if I ask you to translate:
In an ellipse the roll over takes a varying time depending on the part of the circumference in play on the road? So that as the paddles or whatever they are called go around the small parts of the arc they are consuming the most power and when falling down the straight bit or rising up the other side they are neutral.
I really can't get my head around this so maybe it is gibberish.
Let's start again.
The concept is like a tank track.
The troughs on the track have to wait to fill to get the full impact of the design. Then at the bottom as each full trough gets there it sheds. Which means that it is getting all the travel to that point as free play.
Then it goes around the smallest radius at the bottom and sheds the wter.
Czjd!
No I have lost it.
There was something about traction in all that, that escapes me; besides I have just taken twice as many painkillers as I should have and am not quite with it.
Feels good though (between twinges that is.)
Bloody hell ....oh for the chance to go back a few decades and eat properly!!!.
A f*ck! I forgot what I came in here for now and am well past my bedtime. What I need is another week off work to make up fo the damage I did not needing a fortnight off instead. That makes perfect sense to me at the moment but I know I am going to wonder what the f*ck I am/was playing at tomorrow.
Oh yes, the importance of being green is on again next Wednesday. I'd love to see him convert the wheel he's got into one of those.
Ah that's what I meant...
The idea is that the wheel is like an ellipse which means it is only able to work at maximum efficiency if the thing is going slow enough to fill but the more it gets filled the faster it goes until it bottoms out. Sending it through a tube and past a screw would give it the best overall performance wouldn't it?
With a slow feed and not a lot of drop... arrrrggghhh! fegit!
how it worked was anything other than obvious from the picture imho, the possibilities were various.
It doesnt take any power to go round the end curves on a linear belt, other than friction losses, which should be minimal.
Full fill gives max power, but efficiency of the belt changes little with fill level, as long as friction power use is much less than power out. If friction were very high you'd be right.
bottoms out?
which is why this is always done in large scale generation
...you get not much times not much out. And thats the problem. I'd love to see rivers being tapped for power all along their length, but how realistic are the claims on this one?
The message from "Dave Liquorice" contains these words:
Unfortunately not. I lifted the following quote off a site selling booster pumps as the water supply website I also checked didn't quote the statutory minimum.
"The recognised minimum water pressure that a water company must supply water to the consumers stop tap is approximately 1bar, (that is enough pressure to supply water up to 10 metres height from the stop tap in the street, The minimum flow rate is 10 litres per minute.
Water companies have their own targets, this is usually in the region
1.5 to 2 bar or 15 to 20 metres of head or higher. This provides customers with a water pressure that enables such as combi boilers and other devices that require a certain water pressure to function. As the water pressure drops below 1 bar many pressurised devices will not work."
It appears that you're not well. So, your bad manner towards myself (I don't care how you treat others) is understandable, but not necessarely excusable. However, you're forgiven. And that will be reflected in my (if any) future posts to you.
Bzzzt, quite right. Can I blame that on axcesses of festive incahol?
Yours seems very high. 3,300 kWh/yr is the figure usually quoted by suppliers for a "medium user" for their pricing and "savings" estimates. Mine's about 9,500 kWh/yr, but ~70% of that is for the storage heaters in the workshop.
Indeed, and some way of making it work - which ain't easy.
We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember snipped-for-privacy@care2.com saying something like:
There is... what do they say about pictures?
Still strikes me as hopelessly optimistic on the stated power output. "Up to" 1kW, yes, but mostly way, way below that.
Actually, if one were to take the caterpillar trough idea and lengthen it, turn it on its face and steep it in a running stream... it might knock out more power.
The OFWAT site refers to 10m head *and* 9l/min flow at the street stop c*ck. The pedantic could interpret your quote as meaning a 10m static head but substantially less when water is flowing... B-)
So as P = Head(m) * Flow(l/s) * g we have:
P = 10 * (9/60) * 9.81 = 14.715W but you can only get about 70% of that out as electrical power resulting in 10W... note that 9l/min is a very low flow for a half decent stream or brook.
Figures from a commercialy available ultra low head turbine: 1.8 to 2m head, 40l/s flow, gives 300W electrical. So useful amounts of power are available from low heads *provided* you have the flow.
We cook by 'lectric but I shouldn't imagine that uses 10+ units/day. I suspect most goes in the small always on stuff like 2 computers then the stuff that is on for waking hours another computer or two and monitors. And I guess a fridge, fridge freezer and freezer don't help much either...
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.