plaasjaap

A dairy farm in our area went big on bio-gas and save plenty. Have a look at http://www.farmersweekly.co.za/agri-technology/farming-for-tomorrow/affordable-sa-bio-digester-powers-local-dairy-farm/
Also if one wants to spend the money and have an easy to install solution try http://www.biogaspro.com/. Perhaps the farmers and others could convert internal combustion engines driving generators and run them on bio-gas. That is what the Basson brothers did resulting in massive savings. I have found home built Indonesian installation videos on Youtube. That is a poor country (almost like South Africa nowadays) so I guess they look for saving money saving methods wherever they can.

Since then it has been fun trying to convert every single gas appliance that i can put my hand on to see if it can work on biogas. The Alva space heater took a lot of tweaking but it works (so far only on one panel or so), but even the safety cutoff/thermocouple still operates. What one really needs is a huge variety of different sized jets to swop out - it seems to be a very sensitive matter - just too much or just too little and it won't burn or would only burn sort-of. My wife's Smeg (!) has also been stripped and reassembled and it is now a multi-fuel machine... The oven i couldn't get converted and allowed wifey to keep that on LPG as my (unmentioned...) forecast would be that, even if i got it to work on biogas, it won't be as predictable as LPG heat and there goes those nice nice Red Velvet cakes as well as keeping her on board regarding this exciting new energy source...
Below are the two types of gas (es? - one gas many gasses/gees/gases...;-) burning side-by-side. LPG now suddenly looks green compared to the bluer colour of the biogas. Admittedly, the biogas is lower in 'oempf' so the same size flame is less heat and takes a little longer to get something to the boil. The key is just to get more gas to flow whilst still getting the air mixture right.
And all this time, which we are not cooking or I am not testing the gas it is bubbling out of my over-pressure container... Over time one will probably get a very good idea of how much it is really producing, but a couple of nights ago I left the valve open outside. By the morning it was still blowing out, even though the pressure had dropped from about 20mBar to 5. After plugging it in the burner it still boiled the kettle in no time and that is the cup of coffee you can see above... I haven't yet installed a pressure system (tyres on the bag...) as it is operating at max all the rest of the time. 
Next items to convert are gas geysers (at least Dewhot have indicated they have successfully done this and can supply me with the jets) and then... the generator. The latter probably won't happen too soon.

After some tweaking and opening up jets and getting the right air mixture, I managed to have a very nice steady burner flame going by the next morning. And it was coffee-time!

I had learnt that the first couple of 'bloats' will not be very rich in methane and be mostly CO2, but i still tried to light it at the end every now and again... After day 7 I was getting a wee bit worried that I had build a huge CO2 emitting rumen... I mixed it again (pump the thinnest stuff from the bottom outlet tank back to the inlet tank). The next evening i could hardly believe it when i saw the first signs of a magical blue flame...

Hi all
Thought it is about time that I contribute something to this forum. I wanted to start earlier to show how the project progressed, but I was too worried that it might not work...!
It all started after visiting a youngster close to us in the former Transkei - in the corner of his kitchen was a two-plastic-drum-model biogas digester! With about 2L of cattle manure slurry he was cooking his daily meal on a little gas hob. It was an incredible eye opener for me! The concept was just too simple not to try it at home.
We have been living off-grid on solar since being back on the farm for about 4 years now. It has been great, but the one area of improvement is that i still need to buy LPG for cooking and heating. It is not a huge bill, but on the heating front I would love to do much more to heat up the old farmhouse during wintertime. We have also renovated another 8 cottages/living unit which we rent out as I have shown. All operate off-grid but cook with gas mainly. Generally, as you all know, solar is not good at anything to do with heating and this is where gas generally comes into its own.
Attached photos are of Moeghesi's inhouse digester - pipe off the top, straight to hob - and it works! He also had concrete built one outside - but this was not operational due to a crack/gas leak.
 

After some tweaking and opening up jets and getting the right air mixture, I managed to have a very nice steady burner flame going by the next morning. And it was coffee-time!

I had learnt that the first couple of 'bloats' will not be very rich in methane and be mostly CO2, but i still tried to light it at the end every now and again... After day 7 I was getting a wee bit worried that I had build a huge CO2 emitting rumen... I mixed it again (pump the thinnest stuff from the bottom outlet tank back to the inlet tank). The next evening i could hardly believe it when i saw the first signs of a magical blue flame...

Very fascinating!  Please do keep us in the loop!

Hi all
Thought it is about time that I contribute something to this forum. I wanted to start earlier to show how the project progressed, but I was too worried that it might not work...!
It all started after visiting a youngster close to us in the former Transkei - in the corner of his kitchen was a two-plastic-drum-model biogas digester! With about 2L of cattle manure slurry he was cooking his daily meal on a little gas hob. It was an incredible eye opener for me! The concept was just too simple not to try it at home.
We have been living off-grid on solar since being back on the farm for about 4 years now. It has been great, but the one area of improvement is that i still need to buy LPG for cooking and heating. It is not a huge bill, but on the heating front I would love to do much more to heat up the old farmhouse during wintertime. We have also renovated another 8 cottages/living unit which we rent out as I have shown. All operate off-grid but cook with gas mainly. Generally, as you all know, solar is not good at anything to do with heating and this is where gas generally comes into its own.
Attached photos are of Moeghesi's inhouse digester - pipe off the top, straight to hob - and it works! He also had concrete built one outside - but this was not operational due to a crack/gas leak.
 

Hi Guys
I can also now confirm that the 72 40 firmware does indeed take any AVR genny more readily. I have two axperts (not in parralel) and the one with older firmware doens't want anything to do with anything but a proper inverter-generator.

These guys confirmed they have tested the Axpert and it is acceptable... i think it is great that one won't need to replace all our existing components when it comes to replacing batteries!
The sales guy made the following remarks which are sounding nearly convincing:
Die twee sterkste punte wat ons probeer maak met verkope, is die volgende:
 
-          Al ons batterye kan in 1 uur heeltemaal vol gelaai word (alhoewel ons 2 ure aanbeveel).
 
-          Cycles @ %DoD (depth of discharge):
 
a.       3600 cycles @ 100% DoD
b.      5000 cycles @ 80% DoD
c.       7000 cycles @ 70% DoD
 
As ‘n mens bg. siklusse vergelyk met loodsuur en die koste per kWh uitwerk, is ons batterye aansienlik goedkoper as loodsuur.

Resurrecting an old thread, very interesting and applicable to me:
I did our farmhouse (no eskom, not even the option thereof) 3.5 years ago using Outback only (80Amp Flexmax & 3048 Inverter). Due to the reasons above - off grid and days' couriering away if problems happen. Did Outback serve me well? yes and no. Due to cost, i never got (and really needed) the interface (MATE) and the inverter (due to noise and no info/screen on it anyway) went under the floor with batterybank. Flexmax in livingroom (bloody noisy though...). Loong story short - vermin were active at one point under the floor and pissed into the inverter and blew it... Supplier says sorry, my fault no fix or replacement (5 year warrentee). Luckily (after some fighting) insurance pays out... For the price on one 3kw inverter i BUY THREE 4kw axperts. By that time i was already using Axperts elsewhere and completely impressed with them and their flexibility (esp at the price). Now i have two 4kw units (one supplying my house, second to cottage we added) and the thirds at a separate farmhouse we fixed and put on solar.
Altogether i know of about 15 units used (mainly offgrid), and not one single issue yet (except difficulty to get it to take a AVR genny to charge...). They're so quiet, now located in my livingroom and looked after. Flexmax still used for charging (figures given are very nice yes...) but seems like the Aux output (which i used for starting my borebole pump at Float) is not working anymore so will probably switch over to Axpert's SCC soon (to send flexmax for repairs). Axpert's dry contact doing perfectly now to start and stop pump via a contactor. Many basic fuctions on Axperts I use now (like setting Low DC cutoff, AC charge Amps etc) was not an option with OUtback (you have to have Mate) when i had it.
 
I dunno, the 'good' and pricey brands will have hard time winning me over again. I must just find out from you guys how to properly monitor Axpert via ALL these software options developed...? JUST looking for kwh for PV load, bat use and load per day!? Please tell me which, willing to pay as long as it works.. I have read pages and pages of the threads but can't really get understand as they get stuck in 'geek-language'...

Resurrecting an old thread, very interesting and applicable to me:
I did our farmhouse (no eskom, not even the option thereof) 3.5 years ago using Outback only (80Amp Flexmax & 3048 Inverter). Due to the reasons above - off grid and days' couriering away if problems happen. Did Outback serve me well? yes and no. Due to cost, i never got (and really needed) the interface (MATE) and the inverter (due to noise and no info/screen on it anyway) went under the floor with batterybank. Flexmax in livingroom (bloody noisy though...). Loong story short - vermin were active at one point under the floor and pissed into the inverter and blew it... Supplier says sorry, my fault no fix or replacement (5 year warrentee). Luckily (after some fighting) insurance pays out... For the price on one 3kw inverter i BUY THREE 4kw axperts. By that time i was already using Axperts elsewhere and completely impressed with them and their flexibility (esp at the price). Now i have two 4kw units (one supplying my house, second to cottage we added) and the thirds at a separate farmhouse we fixed and put on solar.
Altogether i know of about 15 units used (mainly offgrid), and not one single issue yet (except difficulty to get it to take a AVR genny to charge...). They're so quiet, now located in my livingroom and looked after. Flexmax still used for charging (figures given are very nice yes...) but seems like the Aux output (which i used for starting my borebole pump at Float) is not working anymore so will probably switch over to Axpert's SCC soon (to send flexmax for repairs). Axpert's dry contact doing perfectly now to start and stop pump via a contactor. Many basic fuctions on Axperts I use now (like setting Low DC cutoff, AC charge Amps etc) was not an option with OUtback (you have to have Mate) when i had it.
 
I dunno, the 'good' and pricey brands will have hard time winning me over again. I must just find out from you guys how to properly monitor Axpert via ALL these software options developed...? JUST looking for kwh for PV load, bat use and load per day!? Please tell me which, willing to pay as long as it works.. I have read pages and pages of the threads but can't really get understand as they get stuck in 'geek-language'...

That is pretty much the loads that I have. Peaks are the microwave or inverter welder, general average load is 300-400W in the day and 200W at night. I have a 48V system, 8x 150Ah batteries and 6 x 300W panels, with a generator backup. I know from experience that if my system was just a bit smaller, I would have problems and have to run the generator every day. Currently the generator is only used for an hour or so in winter or when overcast. Now that the days are lengthening, it is not neccesary to run the generator unless there are exceptional loads.
I wouldn't recommend going 24V as you limit the size of the system. Rather go 48v and be done with it.
Staff and cottage are on 12V solar for lighting, solar geyser and donkey for hot water, and wood and gas for cooking.

I'm the other guy here with a 24V system and I'm jealous of the low currents you 48 Volters have to deal with. You can like literally get away with those horrible 105Ah batteries in a pinch and get some decent power out of them :-) As I said it beforem the 24V question is really "Can I get away with it?", and once you start speccing battery banks over 200Ah the answer is rapidly turning into a "no, I cannot get away with it".
There is a small angle on the equipment side, in that 12V/24V stuff is more readily available and often cheaper. I'm from the blue team, as most of you well know, and just take a look through the line-up to see my point, a lot of the more affordable MPPTs are limited to a 24V system. The question still remains, if I cannot get away with it (due to operational constraints on the current side), then you should not do 24V.
I'm happy with my 24V system for now. The direction in which I am taking it is going to be backup of essential loads, and grid-parallel battery up to 1.5KVA max to eliminate base loads. So I can get away with it.
48V is always better than 24V. Always. Just like a Toyota is always better than an Isuzu... but sometimes you can get away with the Isuzu.
(Yes... that was deliberate :-P )

Thanks for all of this info Mike. Turns out i have also put up a similar wind turbine from the same supplier a few months ago and really am glad to see how others find it operating.
Firstly, you have AWESOME wind... I knew our night time wind isn't great and my main motivation was for generating additional charge during cold front weather when solar doesn't manage to replace used energy. But, in the interior, even on cloudy, partly windy days i think the 3kw of panels still generate more than the 2kw turbine over 24h... Yes, it does contribute but ZAR/watt I could've added another 3kw of panels and floated batteries every single day, no matter what the weather be like I think. Since May when i put it up, i can count on my one hand the nights where wind managed to hold the battery bank above 50v. I have 16 x 190ah batteries installed.
The turbine looks cool though... I installed it using an old 9m high windmill stand. It was an old farmhouse we converted into living units, rented out.  Daily use is ave of 10kwh per day(24h) between 4 living units, 6kwh is during night time unfortunately with 6 tv's, 4 laptops and 5 fridge/freezers.
During initial installation i was always going to add more panels to the 3kw so plan was 2 x 5kva axperts (to allow for adding more kw solar - 3kw solar on each) and small backup generator for poor weather patches. the turbine then looked attractive as it's cost was equal to the saving now on one axpert, 1 kw of panels as well as the genny. But i am afraid the turbine is not bringing in the power and options i would've i had hoped for. We just do not have the wind resource here...
So starting to think maybe to try and revert back to original plan, adding the second axpert and more panels. Any one want to buy a basically new 2kw Zonhan (with extra long blades for 'low wind'), controller, dumpload and perhaps awesome vintage stand... (YES, we moved and re-erected it just as DESCRIBED HERE earlier on the thread... how it is done on the farm with tractor, people cables and chaos... can send photos at a minimal cost).
Anyhow, it was an experiment for me... If anybody else in the interior is wondering, it does help/supplement, but not enough I am afraid...

Thanks for all of this info Mike. Turns out i have also put up a similar wind turbine from the same supplier a few months ago and really am glad to see how others find it operating.
Firstly, you have AWESOME wind... I knew our night time wind isn't great and my main motivation was for generating additional charge during cold front weather when solar doesn't manage to replace used energy. But, in the interior, even on cloudy, partly windy days i think the 3kw of panels still generate more than the 2kw turbine over 24h... Yes, it does contribute but ZAR/watt I could've added another 3kw of panels and floated batteries every single day, no matter what the weather be like I think. Since May when i put it up, i can count on my one hand the nights where wind managed to hold the battery bank above 50v. I have 16 x 190ah batteries installed.
The turbine looks cool though... I installed it using an old 9m high windmill stand. It was an old farmhouse we converted into living units, rented out.  Daily use is ave of 10kwh per day(24h) between 4 living units, 6kwh is during night time unfortunately with 6 tv's, 4 laptops and 5 fridge/freezers.
During initial installation i was always going to add more panels to the 3kw so plan was 2 x 5kva axperts (to allow for adding more kw solar - 3kw solar on each) and small backup generator for poor weather patches. the turbine then looked attractive as it's cost was equal to the saving now on one axpert, 1 kw of panels as well as the genny. But i am afraid the turbine is not bringing in the power and options i would've i had hoped for. We just do not have the wind resource here...
So starting to think maybe to try and revert back to original plan, adding the second axpert and more panels. Any one want to buy a basically new 2kw Zonhan (with extra long blades for 'low wind'), controller, dumpload and perhaps awesome vintage stand... (YES, we moved and re-erected it just as DESCRIBED HERE earlier on the thread... how it is done on the farm with tractor, people cables and chaos... can send photos at a minimal cost).
Anyhow, it was an experiment for me... If anybody else in the interior is wondering, it does help/supplement, but not enough I am afraid...

Thanks for all of this info Mike. Turns out i have also put up a similar wind turbine from the same supplier a few months ago and really am glad to see how others find it operating.
Firstly, you have AWESOME wind... I knew our night time wind isn't great and my main motivation was for generating additional charge during cold front weather when solar doesn't manage to replace used energy. But, in the interior, even on cloudy, partly windy days i think the 3kw of panels still generate more than the 2kw turbine over 24h... Yes, it does contribute but ZAR/watt I could've added another 3kw of panels and floated batteries every single day, no matter what the weather be like I think. Since May when i put it up, i can count on my one hand the nights where wind managed to hold the battery bank above 50v. I have 16 x 190ah batteries installed.
The turbine looks cool though... I installed it using an old 9m high windmill stand. It was an old farmhouse we converted into living units, rented out.  Daily use is ave of 10kwh per day(24h) between 4 living units, 6kwh is during night time unfortunately with 6 tv's, 4 laptops and 5 fridge/freezers.
During initial installation i was always going to add more panels to the 3kw so plan was 2 x 5kva axperts (to allow for adding more kw solar - 3kw solar on each) and small backup generator for poor weather patches. the turbine then looked attractive as it's cost was equal to the saving now on one axpert, 1 kw of panels as well as the genny. But i am afraid the turbine is not bringing in the power and options i would've i had hoped for. We just do not have the wind resource here...
So starting to think maybe to try and revert back to original plan, adding the second axpert and more panels. Any one want to buy a basically new 2kw Zonhan (with extra long blades for 'low wind'), controller, dumpload and perhaps awesome vintage stand... (YES, we moved and re-erected it just as DESCRIBED HERE earlier on the thread... how it is done on the farm with tractor, people cables and chaos... can send photos at a minimal cost).
Anyhow, it was an experiment for me... If anybody else in the interior is wondering, it does help/supplement, but not enough I am afraid...

You are correct...but to get off-grid and avoid the nasty R1500pm Eskom 'line-fee' in a rural (bundu) setting it is sometimes worth it.. Mostly (ideally) it is only needed the one or two times per month that very cloudy weather is around and batts are not properly recharged by solar the day before