navitron
 
Renewable Energy and Sustainability Forum
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Anyone wishing to register as a new member on the forum is strongly recommended to use a "proper" email address - following recent spam/hack attempts on the forum, all security is set to "high", and "disposable" email addresses like Gmail, Yahoo and Hotmail tend to be viewed with suspicion, and the application rejected if there is any doubt whatsoever
 
Recent Articles: Navitron Partners With Solax to Help Create A More Sustainable Future | Navitron Calls for Increased Carbon Footprint Reduction In Light of Earth Overshoot Day | A plea from The David School - Issue 18
   Home   Help Search Login Register  
Pages: [1] 2   Go Down
  Print  
Author Topic: AC coupled direct heating thoughts  (Read 2834 times)
camillitech
Hero Member
*****
Offline Offline

Posts: 5401



WWW
« on: March 31, 2016, 06:47:26 PM »

Thanks to Heinz, CharlieB, Raasay Primary School and Bob the fire eater, over the last three years I've managed to acquire a complete grid tied Proven 6Kw turnip. Everything including 15m tower, carbon fiber blades, inverters (3kW Outback and 6kW Aurora) two controllers and a 950Ah forklift pack for less than 2kW of solar panels  Shocked I'll have to spend a couple of K on the turbine head and tower foundations right enough but even so it's still a lotta gear for the money.

Anyway, now comes the tricky bit, trying to integrate this into my 'off grid' system  Huh I can't really 'AC couple' any more kit into my present system without spending much more cash on either sophisticated dumps or another SI6.OH and upgrading the supply from my 'power station' to the house. So what I've come up with is a scheme to use all the kit I already have requiring me to only purchase one extra item, the 6kW diverter.



The 'half baked' plan so far is to do something like the drawing. The 6Kw immerser is already in the 1500lt TS and I'll have a temperature controller in there that'll switch over to an air heater just before the thermostat on the immersion element opens. The export clamp sensor will be on 'AC out' of the 'Outback' and set at say 100w to keep the batteries topped up with a TriStar in diversion mode to keep the batteries safe. There will be a permanent connection to a nearby broadband mast I supply and a transfer switch so that I can use this system in the house should the Sunny Island fail.

I know it's rather complexicated but I have acquired all this kit over the years for next to nothing, all I need is the Immersun type device. As well as providing extra heat into my store and relieving pressure on the Sunny Island this will also give me a completely separate system and 100% redundancy.  

Any thoughts chaps?
Logged

http://lifeattheendoftheroad.wordpress.com/

'Off grid' since 1985,  Proven 2.5kW, Proven 6kW direct heating, SI6.OH, 800ah Rolls, 4.75kW PV ,4xTS45, Lister HR2 12kW, , Powerspout pelton, Stream Engine turgo, 60 x Navitron toobs and a 1500lt store. Outback VFX3048 and 950ah forklifts for backup,
rogeriko
Hero Member
*****
Offline Offline

Posts: 1381



WWW
« Reply #1 on: March 31, 2016, 09:26:25 PM »

There are several immersun type devices out there with 2 outputs i expect you could couple the outputs together to make 6 kilowatts
Logged

camillitech
Hero Member
*****
Offline Offline

Posts: 5401



WWW
« Reply #2 on: March 31, 2016, 10:27:56 PM »

There are several immersun type devices out there with 2 outputs i expect you could couple the outputs together to make 6 kilowatts

Aye Roger, I've found one that'll do the trick, just wondering if it'll all work in harmony, the whole thing hinges on that device not allowing any more than 3kW back into the Outback  sh*tfan
Logged

http://lifeattheendoftheroad.wordpress.com/

'Off grid' since 1985,  Proven 2.5kW, Proven 6kW direct heating, SI6.OH, 800ah Rolls, 4.75kW PV ,4xTS45, Lister HR2 12kW, , Powerspout pelton, Stream Engine turgo, 60 x Navitron toobs and a 1500lt store. Outback VFX3048 and 950ah forklifts for backup,
billi
Global Moderator
Hero Member
*****
Offline Offline

Posts: 8910



WWW
« Reply #3 on: March 31, 2016, 10:33:54 PM »

.... Hi Paul , me not understanding  all right now , but might be  other story  tomorrow  ...touch wood   banghead  but  wout not be a transformer be a help ?  https://www.ecoinnovation.co.nz/p-420-30-kva-variable-ac-3-phase-transformer.aspx 
Logged

1.6 kw and 2.4 kw   PV array  , Outback MX 60 and FM80 charge controller  ,24 volt 1600 AH Battery ,6 Kw Victron inverter charger, 1.1 kw high head hydro turbine as a back up generator , 5 kw woodburner, 36 solar tubes with 360 l water tank, 1.6 kw  windturbine
heatherhopper
Sr. Member
****
Offline Offline

Posts: 347


« Reply #4 on: March 31, 2016, 11:15:01 PM »

Quote
rather complexicated
Like billi I'll be sleeping on it! Appreciate the reasoning and use of available resources though.
First thought would be that this is the time to go completely AC coupled - ready market out there for all that DC stuff you have which would largely fund the relatively modest extra bits you would need. I am biased though!
Logged

Off grid AC coupled, 6kW Proven, 2.8kW PV, SMA SI/SB/WB Inverters, 4x576ah Rolls batteries @ 24v, 25kW Biomass Boiler, Wood Stoves, Spring/Well water. Sorry planet - I did try.
camillitech
Hero Member
*****
Offline Offline

Posts: 5401



WWW
« Reply #5 on: April 01, 2016, 06:47:12 AM »

Morning chaps,

yes Billi, I'd never thought of a transformer, will give it some thought but I don't think it'll help in this instance. I would still need some way of loading the turbine proportionally to stop it stalling.

Hi HH, to go down the total 'AC Coupled' route I'd need another SI6.OH at least, perhaps an SI8.OH or even two 8s my wind capability alone is a PV equivalent (as far as SMA are concerned) of 18kW then I have 1.6kW of hydro and currently 5kW of PV. Methinks max for the SI6 is 11kW of installed capacity when using FSPC. Then I have the problem of having to increase the cabling from my power station to the house. The 6kW turnip would be wired directly to the 'bunker' (on back of house) where the TS is. Also, I already have everything else and the 'Power One' doesn't 'frequency shift' as far as I know.

Cheers, Paul
Logged

http://lifeattheendoftheroad.wordpress.com/

'Off grid' since 1985,  Proven 2.5kW, Proven 6kW direct heating, SI6.OH, 800ah Rolls, 4.75kW PV ,4xTS45, Lister HR2 12kW, , Powerspout pelton, Stream Engine turgo, 60 x Navitron toobs and a 1500lt store. Outback VFX3048 and 950ah forklifts for backup,
heatherhopper
Sr. Member
****
Offline Offline

Posts: 347


« Reply #6 on: April 01, 2016, 11:53:42 AM »

Sorry Paul - my AC coupling suggestion was more tongue in cheek than serious although you are most of the way there anyway in reality.
In my simplistic view if you have reliable FSPC driven load control on the AC side the SI only ever "sees" the portion of AC input required for battery charging (which itself is limited) and FSPC continues to operate normally despite SMA "limits". Can all go wrong if that load control fails I suppose. Certainly adding another SI would give you the required configuration but would be costly and I see this is not desirable.
Don't quite understand where you get 18kW of wind capacity?
If you can't get an Immersun type device to work satisfactorily could you not simply use an SSR to proportionally control diversion to the TS - different control options available and cost possibly less. You already have this kind of set up on the DC side?
Logged

Off grid AC coupled, 6kW Proven, 2.8kW PV, SMA SI/SB/WB Inverters, 4x576ah Rolls batteries @ 24v, 25kW Biomass Boiler, Wood Stoves, Spring/Well water. Sorry planet - I did try.
camillitech
Hero Member
*****
Offline Offline

Posts: 5401



WWW
« Reply #7 on: April 01, 2016, 12:43:02 PM »

Sorry Paul - my AC coupling suggestion was more tongue in cheek than serious although you are most of the way there anyway in reality.
In my simplistic view if you have reliable FSPC driven load control on the AC side the SI only ever "sees" the portion of AC input required for battery charging (which itself is limited) and FSPC continues to operate normally despite SMA "limits". Can all go wrong if that load control fails I suppose. Certainly adding another SI would give you the required configuration but would be costly and I see this is not desirable.
Don't quite understand where you get 18kW of wind capacity?
If you can't get an Immersun type device to work satisfactorily could you not simply use an SSR to proportionally control diversion to the TS - different control options available and cost possibly less. You already have this kind of set up on the DC side?

Aye HH,

the 18kW comes from the 3kW and 6kW total capacity doubled as per SMA recommendation for wind. I did seriously think about relying totally on my AC dumps to ease pressure on the SI and have not ruled it out yet. I need to speak to Hugh about that, I had convinced myself that I needed to upgrade the 50m long cable from the 'power station' to the 'bunker' where the TS is to go down that route. However, if the 6kW inverter is already in the 'bunker' I guess I don't in reality, as any power produced by that would be going straight into the store.
I had thought I'd 'future proofed' the cabling issue by running everything in a 100mm duct but that's well full now!! A bit of forethought and I'd have laid two or even three, one for AC, one for DC and one for control/Ethernet but 'you live and learn' hey.

Cheers, Paul
Logged

http://lifeattheendoftheroad.wordpress.com/

'Off grid' since 1985,  Proven 2.5kW, Proven 6kW direct heating, SI6.OH, 800ah Rolls, 4.75kW PV ,4xTS45, Lister HR2 12kW, , Powerspout pelton, Stream Engine turgo, 60 x Navitron toobs and a 1500lt store. Outback VFX3048 and 950ah forklifts for backup,
Mostie
Sr. Member
****
Offline Offline

Posts: 495



« Reply #8 on: April 01, 2016, 03:40:39 PM »

Paul, what happens if the 3kw inverter goes "offline"  assuming it will take the GTI and the big diverter with it  help sh*tfan    fingers crossed!
Logged

2x Solis PV = 1.875 kW, Mitsubishi inverter heat pump. Yorkshire Boiler Stove.
camillitech
Hero Member
*****
Offline Offline

Posts: 5401



WWW
« Reply #9 on: April 01, 2016, 03:58:38 PM »

Paul, what happens if the 3kw inverter goes "offline"  assuming it will take the GTI and the big diverter with it  help sh*tfan    fingers crossed!

Hi Mostie,

firstly the turnip voltage builds up to around 440VDC when the 'over voltage' protection kicks in (big resistors) but these are more a 'safety net' for the inverter. The Proven turbines are quite happy running off load, which is what would happen if the protection and inverter failed. My neighbours Proven ran through several storms and a hurricane unloaded and took no harm, in fact, on battery charging models that's their 'third line of defence' if both dump loads and 'trickle charge' circuits fail. The unloaded turbine simply 'cones', speeds up slightly and makes more noise.

Cheers, Paul
Logged

http://lifeattheendoftheroad.wordpress.com/

'Off grid' since 1985,  Proven 2.5kW, Proven 6kW direct heating, SI6.OH, 800ah Rolls, 4.75kW PV ,4xTS45, Lister HR2 12kW, , Powerspout pelton, Stream Engine turgo, 60 x Navitron toobs and a 1500lt store. Outback VFX3048 and 950ah forklifts for backup,
Fionn
Hero Member
*****
Offline Offline

Posts: 537


« Reply #10 on: April 01, 2016, 04:24:40 PM »

I realise you're making best use of kit you have already but the whole affair seems hugely complex for something that essentially just turning mechanical energy into heat.
Surely a controller exists that will PWM the DC output of the turbine directly into a resistive load based on either the DC voltage or an RPM signal from the turbine?
Logged

6.75kW PV - 2.75kW East, 1.5kW South, 2.5kW West. 3 x Flat Plate Solar Thermal with side arm FPHE on 268L cylinder
camillitech
Hero Member
*****
Offline Offline

Posts: 5401



WWW
« Reply #11 on: April 01, 2016, 05:31:27 PM »

I realise you're making best use of kit you have already but the whole affair seems hugely complex for something that essentially just turning mechanical energy into heat.
Surely a controller exists that will PWM the DC output of the turbine directly into a resistive load based on either the DC voltage or an RPM signal from the turbine?

I'm sure you're right Fionn but the Outback and battery bank are already installed in the 'bunker'. I got the battery bank given, the Outback 'for buttons' and fitted it some months ago as a 'back up'. Same with all the other kit, TriStar was free, the Aurora and wind interface came with a load of other kit for less than the price of a festival ticket and I already have all the cabling and switch gear. It's no more complex than the rest of my kit and it does give me complete redundancy for the price of a solar diverter, if of course it works that is  Grin Sure, if I was starting from scratch I'd be thinking along the lines you suggest, I can even lay my hands on a Proven 'Direct heating controller' which does exactly what you recommend. However, by adding just a couple of switches I can disable my 'AC coupled' solar in the depths of winter and feed the turbine output into the SI's grid thus running other electrical loads and charging my batteries. Solar isn't worth a feck here in the winter, 5kW of solar PV gave us just 148kWh in Dec/Jan and 60 tubes nothing! my 2.5/3.2kW Proven on the other hand put out 1718kWh. Come the summer it's the other way around right enough Jun/July 863kWh PV and 360kWh wind. The thing is we're TOTALLY electric bar the cooker and I'm aiming for ZERO generator usage and an electric car. So far we've run the generator 117 hours in 13 months but by next year I want that to be 0  Grin

Cheers Paul
Logged

http://lifeattheendoftheroad.wordpress.com/

'Off grid' since 1985,  Proven 2.5kW, Proven 6kW direct heating, SI6.OH, 800ah Rolls, 4.75kW PV ,4xTS45, Lister HR2 12kW, , Powerspout pelton, Stream Engine turgo, 60 x Navitron toobs and a 1500lt store. Outback VFX3048 and 950ah forklifts for backup,
Fionn
Hero Member
*****
Offline Offline

Posts: 537


« Reply #12 on: April 01, 2016, 05:36:21 PM »

That's a fair point Paul, however if I were in your suggestion I'd probably flog the stuff you don't need and use the proven controller. The profit could be put away for when your main system needs new batteries or whatever. I can't help but think that the battery bank you have on this system will be pretty under utilised.
All that being said, you'll have a great system when it's done and super redundancy as you say, that's obviously of more value to you.
I'd just be nervous of the time it would take to maintain/monitor and the large number of possible failure points.
Logged

6.75kW PV - 2.75kW East, 1.5kW South, 2.5kW West. 3 x Flat Plate Solar Thermal with side arm FPHE on 268L cylinder
camillitech
Hero Member
*****
Offline Offline

Posts: 5401



WWW
« Reply #13 on: April 01, 2016, 06:11:26 PM »

Hi Fionn,

living in the sticks I rarely sell anything, bit of a siege mentality  Roll Eyes probably end up buying the controller anyway  banghead what you say makes perfect sense and I'd probably advise anyone else to do the same, but I do love tinkering about with all those shiny red, yellow and silver boxes  Roll Eyes Truth is I really must get out more  wackoold Do you think it'll work though  Huh

Cheers, Paul
Logged

http://lifeattheendoftheroad.wordpress.com/

'Off grid' since 1985,  Proven 2.5kW, Proven 6kW direct heating, SI6.OH, 800ah Rolls, 4.75kW PV ,4xTS45, Lister HR2 12kW, , Powerspout pelton, Stream Engine turgo, 60 x Navitron toobs and a 1500lt store. Outback VFX3048 and 950ah forklifts for backup,
guydewdney
Hero Member
*****
Offline Offline

Posts: 4320



« Reply #14 on: April 01, 2016, 06:55:08 PM »

if the 6kw immersun device cant let any more than 3kw 'past' it then you need the secondary load (after the first immersion is 'satisfied') to be 'infinate' without a thermal trip, eg a sauna heater like mine.
Logged

Pic of wheel on day 1
7.2kW Waterwheel and 9.8kW PV
Pages: [1] 2   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.20 | SMF © 2013, Simple Machines
SMFAds for Free Forums
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!