Funds plea to launch £500k ‘river turbine’ (From The Oxford Times)

It doesn't seem that long ago since the people in Osney were complaining about the noise from Hyrdro-electric plant in the river...

Oh wait, it was only in January...

http://www.oxfordmai
l.co.uk/news/yourtow
n/oxford/9455846.Sto
p_the_whining__hydro
electric_generator_i
s_too_noisy/

£500,000 to generate electricity for 50 homes. Most of the cost met from grants and loans - my taxes no doubt.

This is an expensive vanity project. No more, no less.

Oh, and Damian Fantato, telling us that it will produce 150 MWh of energy is meaningless unless you say over what period: a week? a month? a year? It's probably per year - in which case the 50 homes figure is fairly optimistic.

Doc,,, 150MWh, the h being hour: 1 Megawatt hour = 1000 Kilowatt Hours (Kwh)

Darkforbid wrote:
Doc,,, 150MWh, the h being hour: 1 Megawatt hour = 1000 Kilowatt Hours (Kwh)

It's supposed to be 150MWh per year according to this website - as doc says it's a pretty meaningless figure as reported.

http://www.energysha
re.com/west-oxford-c
ommunity-renewables

These sort of projects are not 'vanity projects'. It's only through community led projects like this that we get a chance to try out and develop sustainable energy generation. Once methods are proved then economies of scale bring prices crashing down - solar pv costs have halved over the last 3 years.

200 projects like this potentially providing power for 10,000 homes could be built for the money lost by the recent government rail operator tender ****-up.

Water turbines have been generating electricity for decades already, huge, large, small and domestic sizes. Well before wind turbines were thought of.
Small scale plants are rarely economic and its always possible to calculate the cost/benefits of construction before hand.

Andrew:Oxford wrote:
It doesn't seem that long ago since the people in Osney were complaining about the noise from Hyrdro-electric plant in the river...

Oh wait, it was only in January...

http://www.oxfordmai

l.co.uk/news/yourtow

n/oxford/9455846.Sto

p_the_whining__hydro

electric_generator_i

s_too_noisy/

To be fair it was a different bunch who complained about the noise at Osney Mill turbine. And with good reason. It was put in without consulting neighbours and made a racket.

museli wrote:

Darkforbid wrote:
Doc,,, 150MWh, the h being hour: 1 Megawatt hour = 1000 Kilowatt Hours (Kwh)

It's supposed to be 150MWh per year according to this website - as doc says it's a pretty meaningless figure as reported.

http://www.energysha

re.com/west-oxford-c

ommunity-renewables

These sort of projects are not 'vanity projects'. It's only through community led projects like this that we get a chance to try out and develop sustainable energy generation. Once methods are proved then economies of scale bring prices crashing down - solar pv costs have halved over the last 3 years.

200 projects like this potentially providing power for 10,000 homes could be built for the money lost by the recent government rail operator tender ****-up.

If 150Mwh is the annual output it makes it similar in size to the existing Osney Mill turbine . My rough calculations using feed in tariffs and export prices show returns of something like £44,000 per year - so good for somebody?

But how is this scalable? Are there many places you can put these things - you need drop in level - and 50 homes is nothing for a city like Oxford. Don't we need bigger thinking than this?

Darkforbid wrote:
Doc,,, 150MWh, the h being hour: 1 Megawatt hour = 1000 Kilowatt Hours (Kwh)

Yes. I'm not an idiot.

Multiply power by time, and you get energy. Quoting an electrical energy figure without saying the period over which it is generated tells us nothing.

And @museli, economies of scale help, but the general principle of turbines has been around a while, so there isn't that much technology to prove. You observe that 200 such projects would supply energy to 10,000 homes: that means that if Oxford had 200 suitable mill-races, they would still provide a fairly small fraction of the energy the city needs.

Sustainable energy is a good thing: but overblown claims and wildly optimistic assumptions really don't help.

"Yes. I'm not an idiot.

Multiply power by time, and you get energy. Quoting an electrical energy figure without saying the period over which it is generated tells us nothing."

OK maybe I explained badly, you know when your driving it's quoted as MPH, which is miles covered per hour, MWh is Megawatts per hour... The hour being the period of time,,, you somehow think is missing

Please object to the planning application. There is an hydro unit in the Osney Mill which, I understand, will take the majority of flow that is available as they had their licence first. These are very vain people. This would be 100 yards downstream from the lowest bridge on the Thames. I understand that the river levels have to be kept low because of the bridge so the chance of the unit working would be sporadic. One hydro unit is enough. This is a complete white elephant.

I don't see how this is sensible or viable. The proposed turbine will get what little water is left after Farmoor has taken enough for drinking water and the existing unit at the mill is running at full capacity. In summer it won't spin at all and in winter the river level in the weir pool comes up so high that there will hardly any difference in height and so it won't generate much electricity.

My friend has a boat and told me that he doesn't go near Osney anymore because the unit at the mill makes the river there dangerous. He has been boating in Oxford for 15 years and he said there are many others who feel the same. Surely another unit will make Oxford dangerous for boaters.

cowleycowconjurer wrote:
I don't see how this is sensible or viable. The proposed turbine will get what little water is left after Farmoor has taken enough for drinking water and the existing unit at the mill is running at full capacity. In summer it won't spin at all and in winter the river level in the weir pool comes up so high that there will hardly any difference in height and so it won't generate much electricity.

My friend has a boat and told me that he doesn't go near Osney anymore because the unit at the mill makes the river there dangerous. He has been boating in Oxford for 15 years and he said there are many others who feel the same. Surely another unit will make Oxford dangerous for boaters.

Spot on CCC. Arrogant sandal knitters.

How very lovely for the people who live in the 50 homes on Osney Island that will benefit from guilt free energy or is it? Has any one done the green equation on projects like this? How much carbon does it take to manufacture and install a unit like this versus how much is saved in the energy produced? Does anyone that is part of this project care or are they too busy polishing their trendy green halos?

Just been speaking to a friend of mine who worked for the Environment Agency. Apparently the original plans submitted were to have the cedar cut down! Very green. Maybe this has more to do with somebody making some cash than a "model community" making a difference.

Darkforbid wrote:
"Yes. I'm not an idiot.

Multiply power by time, and you get energy. Quoting an electrical energy figure without saying the period over which it is generated tells us nothing."

OK maybe I explained badly, you know when your driving it's quoted as MPH, which is miles covered per hour, MWh is Megawatts per hour... The hour being the period of time,,, you somehow think is missing

I can see why you're confused, but kWh is a unit of energy, it's confusing because the units have time in it. But the figure is meaningless unless we know over what period of time that amount of energy is produced in.

For example the average UK house (according to the Department of Energy and Climate Change) uses about 4.8kWh (of energy) per year. Your electricity bill will be in kWh over the last month or quarter.

Or to use your car analysis properly, it's a bit like saying "My car does 30miles". Yes 30miles, but when? Per hour? Per day?

NinjaBiscuits wrote:

Darkforbid wrote:
"Yes. I'm not an idiot.

Multiply power by time, and you get energy. Quoting an electrical energy figure without saying the period over which it is generated tells us nothing."

OK maybe I explained badly, you know when your driving it's quoted as MPH, which is miles covered per hour, MWh is Megawatts per hour... The hour being the period of time,,, you somehow think is missing

I can see why you're confused, but kWh is a unit of energy, it's confusing because the units have time in it. But the figure is meaningless unless we know over what period of time that amount of energy is produced in.

For example the average UK house (according to the Department of Energy and Climate Change) uses about 4.8kWh (of energy) per year. Your electricity bill will be in kWh over the last month or quarter.

Or to use your car analysis properly, it's a bit like saying "My car does 30miles". Yes 30miles, but when? Per hour? Per day?

*Correction, 4.8MWh per year.

OMG! This is the way it works, they'll buy a hydro unit, they're sold n various sizes, like 50MWh, 150MWh, 300MWh and various other outputs.

I can't see where the confusion is, Hydro isn't like wind or solar... when its in the water flow its kicking out it's full MWh,,, constant, the only thing that's going to stop it is stopping the water,,,

*(what part of per h, don't you people understand)

Darkforbid wrote:
OMG! This is the way it works, they'll buy a hydro unit, they're sold n various sizes, like 50MWh, 150MWh, 300MWh and various other outputs.

I can't see where the confusion is, Hydro isn't like wind or solar... when its in the water flow its kicking out it's full MWh,,, constant, the only thing that's going to stop it is stopping the water,,,

*(what part of per h, don't you people understand)

The turbine manufacturer will specify a max power output which will be 45kW if it's same as existing Osney Mill turbine

The article says it estimates the turbine would produce around 150 MWh of electricity. This is almost certainly annual figure though it doesn't say.

Power output of the Osney Mill turbine certainly isn't constant and is currently around 24 kW from live log.

A Scroat wrote:
Please object to the planning application. There is an hydro unit in the Osney Mill which, I understand, will take the majority of flow that is available as they had their licence first. These are very vain people. This would be 100 yards downstream from the lowest bridge on the Thames. I understand that the river levels have to be kept low because of the bridge so the chance of the unit working would be sporadic. One hydro unit is enough. This is a complete white elephant.

Water doesn't stop flowing after it's passed through a turbine, it just keeps on going - although it can lose "head". That's why the turbines at Whitchurch can still generate power even after it's generated power at Osney Mill.

Isn't the Queen Elizabeth II Bridge at Dartford the the lowest crossing on the Thames?

Andrew:Oxford wrote:

A Scroat wrote:
Please object to the planning application. There is an hydro unit in the Osney Mill which, I understand, will take the majority of flow that is available as they had their licence first. These are very vain people. This would be 100 yards downstream from the lowest bridge on the Thames. I understand that the river levels have to be kept low because of the bridge so the chance of the unit working would be sporadic. One hydro unit is enough. This is a complete white elephant.

Water doesn't stop flowing after it's passed through a turbine, it just keeps on going - although it can lose "head". That's why the turbines at Whitchurch can still generate power even after it's generated power at Osney Mill.

Isn't the Queen Elizabeth II Bridge at Dartford the the lowest crossing on the Thames?

No it isn't. The Botley Road bridge is the lowest not the last. By the way, these precious people probably don't realise that when the river rises the hydro unit cannot pass the water quick enough through it as the water below it has risen and acts as a wall. Ask the people at Osney Mill. The higher the water below it the less efficient it is.

The QEII bridge at Dartford compared to the Botley Road bridge! Have you ever actually been to Osney before Andrew? Of course water doesn't stop flowing. The point is that these projects require licences so that they don't run the river dry when there is not enough flow for the other activities on the river. For the majority of a normal year on the Thames, the flow rate is only just enough for the existing hydro unit to run because the river level has to be preserved for farmoor to obtain drinking water and enough water for boats navigating. The proposed scheme is not downstream of the existing so water will not flow through one and then get used by the other. They are in fact parallel and therefore are in direct competition for water. In other words as others have said already; there is not enough flow for it to be worthwhile. I'm all for green energy but this just seems to be a vanity project aimed at getting a few people some cash. Forget everybody who uses the river, we're too busy being "green"

cowleycowconjurer wrote:
The QEII bridge at Dartford compared to the Botley Road bridge! Have you ever actually been to Osney before Andrew? Of course water doesn't stop flowing. The point is that these projects require licences so that they don't run the river dry when there is not enough flow for the other activities on the river. For the majority of a normal year on the Thames, the flow rate is only just enough for the existing hydro unit to run because the river level has to be preserved for farmoor to obtain drinking water and enough water for boats navigating. The proposed scheme is not downstream of the existing so water will not flow through one and then get used by the other. They are in fact parallel and therefore are in direct competition for water. In other words as others have said already; there is not enough flow for it to be worthwhile. I'm all for green energy but this just seems to be a vanity project aimed at getting a few people some cash. Forget everybody who uses the river, we're too busy being "green"

This potential to 'run the river dry' and the idea these projects are in competition with each other sound like nonsense to me. I understand the Thames flow through Oxford is over 1 million litres per minute. Where does all this water get stored that screw turbines might run the river dry? There's no dam or reservoir! Osney Mill turbine uses a flow of less than 200,000 litre per minute, so you could put 5 of these across the Thames and, with proper design, the worse that would happen to the flow is it would back-up and bypass them (though I doubt this would really be possible because of the effect on navigation).

Yes there seem to be obvious problems with the way Osney Mill turbine has been implemented allowing the outflow to cause problems for boaters, I'm quite sure this could have been avoided with proper planning.

Archimedes screw turbines are a relatively new technology and have only been in use in the UK for about a decade, installing lots of them aroung the country seems a good way of proving their capability and long term reliability. They have the potential to be reversed and used as pumps and may turn out to be very useful as a component of small scale, local pumped storage with sounds to me like a good way to provide much needed combined local water storage and intermittent renewable power storage.

My point was not that having a new turbine would run the river dry. If you notice i mention that a licence is required. Such a licence prevents projects using excessive water to the detriment of navigation and ecology in a stretch of the river. In summer conditions when the weirs are fully closed the impact of the two turbines running at full tilt would be enough to run the river into a muddy bog. If you remember in the summer of 2011 Osney lock had to be closed for a day because somebody left the sluices half open causing the river to drop a foot. Port Meadow doesn't look pretty when the river is down a foot and two turbines woud lower it further than half a set of lock sluices. So it is not nonsense to suggest that they could run the river dry. They 'could' run the river dry. However my point was that because the licence would protect this from happening; for the majority of the year there would not be enough flow for both to run. Therefore making the second turbine unsustainable. The flow rates you mention vary considerably but you might want to find out how long the Osney mill turbine was turning for during the summer of 2011. This was a slightly dry summer but not an unusual one. I'll tell you to save you the trouble. Two days. So where is the leftover for another turbine?

I tried to comment on the planning application but it's not clear if comments are still being accepted as we are near or at the cut off. So I will put my comments here ...

The flood risk assessment covers surface drainage and flood risk to the site, but does not examine in detail the impact that it may have on downstream areas from changes in flow. From the Environment Agency website, "hydropower schemes can have serious impacts on the environment, including changing river flows, which in turn can affect fish migration. Downstream habitats can also be adversely affected and flood risk increased."

Will more water have to be diverted from other streams or reservoirs to drive the turbine?

Why no mention of the existing Archimedean screw turbine at Osney Mill, which is very close to and roughly in parallel with the proposed screw? There could be lessons to learn, e.g. from the ongoing investigation and attempts to reduce noise. Will there be a competing demand at times of low water?

The figures quoted in press article show a high cost. As this is largely funded from grant money it would be good to see some analysis of why this scheme is proposed over other carbon cutting measures.

Wanchai wrote:
I tried to comment on the planning application but it's not clear if comments are still being accepted as we are near or at the cut off. So I will put my comments here ... The flood risk assessment covers surface drainage and flood risk to the site, but does not examine in detail the impact that it may have on downstream areas from changes in flow. From the Environment Agency website, "hydropower schemes can have serious impacts on the environment, including changing river flows, which in turn can affect fish migration. Downstream habitats can also be adversely affected and flood risk increased." Will more water have to be diverted from other streams or reservoirs to drive the turbine? Why no mention of the existing Archimedean screw turbine at Osney Mill, which is very close to and roughly in parallel with the proposed screw? There could be lessons to learn, e.g. from the ongoing investigation and attempts to reduce noise. Will there be a competing demand at times of low water? The figures quoted in press article show a high cost. As this is largely funded from grant money it would be good to see some analysis of why this scheme is proposed over other carbon cutting measures.

I have spoken to the E.A. and it seems that Farmoor have priority over everyone. If there is enough water after they have been pumping then the Osney Mill turbine will get 65 % and this white elephant will get the rest but that is certainly not every day. The water level has to be kept to a low level because of the NAVIGATION of boats under the lowest bridge on the Thames. The boaters pay a licence to be able to do this, a point that will go over the heads of the sandel knitters.