Few Questions and an update

[Allan1971]

Hi there everyone.

Well farmwork has seriously put my hydro scheme on the back burner , but now its right at the front again .
Have been talking to my national park 'Community Renewable energy officer' who was great to talk too an mentioned something !!!
He has heard of acidic water destroying the turbines . Now the water that flows in the ditch where I'm planning to take the water from starts life in hills form redundant iron ore mine . Now its does have a Reading effect near too the collapsed entrance but 1/2 a mile away it runs clear . anybody with something similar ?

Now my flow , currently I've 18m of 110mm soil pipe in the ditch running full with around 7 -8 ltr excess running over the dam . Now with 200m pipe length and 22 meter of head height i am sure that I can run a 3kw but during the driest spells in summer !!!! flow dropped to around 5 -6 ltr a sec. Now it had hoped that i could turn of 1 of the jets at the turbine and still maintain 50% of the out put , am I in cuckoo land or is this possible .
It has been mentioned about fitting 2 turbines but the cost of this makes me very hesitant .

Any thoughts .

Allan

[billi]

Allan

I might be of no help    , but varying flow can be dealt with , but depends on your ideas ....

I hope others will correct me , but a 2 nozzle 230 Volt AC Turbine does not mean that you can turn one nozzle off in summer and still get  clean 230 volt AC at 50 HZ with lesser watt

My opinion is , that it will work if you gridtie a turbine with two nozzles to a DC gridtie inverter (that means changing to DC first) to allow  the full performance with lesser watt...

I might be wrong here , but my 230 Volt turbine would not produce anything good for me , if the flow and head isnot right ie if i reduce the flow it will just  reduce volt and Herz  ( sad enough that it is still producing power and i can runn a hairdryer on it , but my house would not accept that poor performance )

So i always think about how windturbines work with different speed (power available) and still i am searching for that answer for waterturbines   (somehow i think i know the answer  )


So ask for a DC Turbine or a 3 phase ("wild" dont know what that makes the difference ) AC with a separate rectifier  to feed a gridtie inverter

sorry for confusing

Billi

[Allan1971]

Must admit Billi i got lost there but i think I've made my mind up on fitting 2 turbines , got a 1.5kw and a 1.1kw in mind , i think that way i willl have enough flow to at least run one of them in the driest of weathers during the wet summers were getting used to . I listen to my dad talking about summers gone past with envy . haven't made hay in June for 3 years and i long for a year where its just the odd shower to keep things growing and a winter to kill all the bugs . anyway digressed there.

So a week this Friday got a man from environment agency coming to look at what i want to do and tell if a need an abstraction licence !! hmmm gona be interesting I'm sure
I'm sure i dint and all people locally agree , whats yer betting there i someone who disagrees

[billi]

Must admit Billi i got lost there

No worries  not your fault 

How do you want to use the power ? Export, use it direct yourself or store as well in Batteries ?

Good Luck

Billi

[Allan1971]

Well currently I'm using between 26 and 30kw of electric per day so first of its to reduce my bills but I'm definitely gonna connect to the grid so i can export , I know the are people out there that would say disconnect but I need a guaranteed supply to give 4-6kw of power at any time . When I'm grinding corn for my stock sometimes the energy meter i have connected reads 4.9kw .

Anyway so I'm thinking ahead here as you never now if there are gonna be some blades whizzing around on top of a building and there are possibility's of another hydro scheme , but that would need some  serious planning and capital outlay .

[dhaslam]

There shouldn't be any worries about the cost of the equipment versus payback.   Electricity isn't going to  fall in price anytime soon.   It is worth sizing the turbines carefully.  A ratio  of 1:2  can gives the best spread of options for two  turbines.  The size should maximise the overall output for the year  and not worry about losing a few weeks  output in summer. 

[billi]

Allan

that is why i asked earlier on , if you like to export into the grid you should plan ahead , with two turbines  you will need 2 gridtie inverter i asume and as far as i know one bigger 3 phase model will work better with a inverter and i think you get the model with more nozzles

Perhaps you havenot seen this http://www.navitron.org.uk/forum/index.php/topic,6589.0.html

Billi

[dhaslam]

I wondered about combining the two  but I think  that each uses a rectifier from the three phase output  into DC.  Then it needs a grid tie  inverter that can take two DC inputs  at different voltages.  The solar  ones  can take separate strings of PV panels but can a solar grid tie inverter be used for hydro?       

[SteveH]

The solar  ones  can take separate strings of PV panels but can a solar grid tie inverter be used for hydro?       

 I think the solar GTI's insist on same output strings... All the ones I looked at did, but don't take this as the definitive answer....

[Allan1971]

  Looks like things are getting a little technical and dare i say exspensive !! . May just be simpler to fit a single 3kw turbine .

I see in the thread Billi showed it was sugested a 6kw could be cut down to produce 3kw by closing one of the jets of , is this the same for the 3kw . I realy belive im just on the edge of powering one of these but its in the summer months when flow drops of to 6 - 8 ltr/sec . is this enough to get 1.5kw   

[billi]

Allan

the problem with these 230 Volt AC turbines is , that you need the correct flow and head .... to meet the requirements of your house/gear  and if  i reduce the flow from my 1.1 kw rated 230 Volt unit , it would still produce energy, but i can not use it , because the Volt drops for example to 140 volt  , ok i could still connect a hair dryer direct but would only work at half power or so

So it doesnot make sense to me to get  two 230 volt turbines to direct supply your house , if you think of exporting later

A windturbine works with varying RPM as well as a Car Alternator ( both are 3 phase wild AC (i think ) and rectrified into DC

Both would supply  power  that can be used , may it be Battery charging or inverting to export into the grid
Same i asume will happen to a waterturbine if you reduce the flow (close one nozzle off) Still produce power ( an AC 230 Volt wouldnot work this way )  

There are several waterturbines available  with upto 4 jets  to give you all the options  

I have my reserves to 230 volt AC turbines , if you want to grid tie them later , but i am off grid and not the expert

My preverence for a longtherm  setup would be a 3 phase turbine  rectrified into DC  connected to Gridtie inverter or a MPPT solar chargecontroller ( if you need to go off grid later ) = you can grid tie or/and be offgrid

Again i didnot mean to make it so complicated and hopefully others have more staight forward words then me  

And by the way   if there is not a good payback for grid tie  (should be good with hydro )

grinding corn for my stock sometimes the energy meter i have connected reads 4.9kw faint.

  would not worry me too much , if there is a constant source of power .....

for an off grid idea i can help straight away   , but will cost a bit   , not me ...
Billi

[camillitech]

Hi Billi, Allan,

"I hope others will correct me , but a 2 nozzle 230 Volt AC Turbine does not mean that you can turn one nozzle off in summer and still get  clean 230 volt AC at 50 HZ with lesser watt"

This statement is cobblers  there are several multinozzle turbines on the market designed to run at varying flows whilst producing clean AC and even the Navitron can have its single nozzle easily changed to produce 50hz from different flows/loads with the same head.

http://www.hipowerhydro.com/ for one and http://www.microhydropower.com/ is another and even http://lifeattheendoftheroad.wordpress.com/2008/02/07/the-harris-hydro-turbine/ have an AC one under developement.

Good Luck, Paul

[Allan1971]

Thanks everyone for leaving their comments .
feel like I'm but i think i can see a way forward .
Rung my electrician up and he's gonna come out to have a talk , if anyone can work out how to run 2 turbines side by side he will.

Hi Billi, Allan,

"I hope others will correct me , but a 2 nozzle 230 Volt AC Turbine does not mean that you can turn one nozzle off in summer and still get  clean 230 volt AC at 50 HZ with lesser watt"

This statement is cobblers  there are several multinozzle turbines on the market designed to run at varying flows whilst producing clean AC and even the Navitron can have its single nozzle easily changed to produce 50hz from different flows/loads with the same head.

http://www.hipowerhydro.com/ for one and http://www.microhydropower.com/ is another and even http://lifeattheendoftheroad.wordpress.com/2008/02/07/the-harris-hydro-turbine/ have an AC one under developement.

Good Luck, Paul

I  completely understand where you are coming from with respect to the reduced flow into a turbine .
I just think this needs serious head scratching

 

[guydewdney]

I tried to parrallel two PM 3 phase generators - both on the same layshaft, same spec, same belts etc etc.

Ever time I tried, one got very hot and the other was cold - indicating that one was doing all the work.

You will need to separate them completely imho - even though the maths says otehrwise...

[billi]

Rung my electrician up Grin and he's gonna come out to have a talk , if anyone can work out how to run 2 turbines side by side he will.

i would have no problem to run 2 or 20 water turbines in parallel  easy

what would bother me from the start is, if i would like to export the power from these turbines  at a later stage to find out i should have got  other gear    (like a 3 phase unit as an example)

Billi