Biogas - anyone tried it?

[SHoggard]

This is related to Markit's question about Septic Tanks, but rather than hijack his thread I thought I'd start one:

Has anyone tried to install a domestic Biogas Digester (or generator) in Bali?

I thought these were mega-structures until I found myself doing some research a few years back into China's environmental problems and discovered that the government there is subsidizing 50% of the cost of household biogas generators for farmers - so I dug deeper and found:

• They cost about US$1,000 (or $750 in Tanzania !)
• They're very, very, low-tech
• Can be built by the villagers (or expat) themselves

Basically they replace the Septic Tank - dig a hole in the ground, line it with plastic, bricks, more plastic, stick a lid on it, shove in a few tubes & pipes down the hole .... then dump your biodegradable waste in - poo from the loo, cuttings from the garden. last night's food scraps, I'd imagine beans are quite effective in this context :highly_amused:.

As the scrap rots, it generates methane - which it does in landfill anyway - but the methane gets sequestered and piped into the kitchen to the cooker.

Ok, so it isn't quite that simple, but it works, the Chinese have installed more than 20 million individual household biogas digesters in rural areas they provide heat and light in communities that are off the grid: here's a video link Biogas in China - YouTube

Looks good, though personally I wouldn't recommend using the gas for lighting (as seen in the video) particularly with an alang alang roof.

Might also be a solution to Markit's mozzie problem - gas the little buggers! :icon_rolleyes:

 

[kiwi]

I am just working on a large project to convert waste into bio gas, a little bigger than you want 7 tank at 7 mega litres each.
It would be a great concept for the Bali villages to run a common unit, the gas take off would run the generators and power a local waste water treatment plant and have excess power to sell to the grid. Would help stop the ground water being contaminated from all the septic tanks:icon_mrgreen:

 

[SHoggard]

Just what I was thinking

It would make an interesting (and quite cheap) community relations project for expats who are having problems with the locals (other horror-story threads about villagers demanding fees for using access roads they don't own.... etc etc!).

It doesn't look like rocket-science.

But you're right: 7x7 mega litre tanks would be a little hard to fill & I hope I don't have a need to!

 

[BKT]

Hey Kiwi are you able to earn carbon credits from what you're doing?

A guy I knew a while back was looking at doing the same thing. Selling these things to farmers at below cost price, then recouping the money from carbon credits he earned. Only difference is that farmers would use cow manure instead of human waste.

What sort of price are you looking at to have one put in?

 

[kiwi]

Hi BKT,
I am only involved in the tanks, the size of the project I am sure they would have looked at that side of things.
There are alot of small units around in kit form that would suit applications in Bali, UK pig farms have been using them for years.

 

[SHoggard]

There is a bio gas project in Bali

I just came across this: Green Microfinance: Backyard Biogas in Bali, Indonesia Kiva Stories from the Field

Seems the cost for a domestic biogas digester would be in the region of 7m

 

[BKT]

I asked the guy who was looking at selling these things if he ever got into it, his company has moved away from generators and has gone into something else. He did give me the details of the main company here who installs these things though

Biogas Rumah

Website is in Bahasa

The head honcho's are Robert DeGroot and his Balinese counterpart Pak Suarja

PM me if you want their email addresses

 

[mariaandrobert]

Save on LPG?

Interesting way to maybe save on elpiji. Might be sitting on a bigger bomb though, lol. However I doubt pressures are at all substantial. I don't care to farm pigs to have enough feedstock. Not sure two of us could get a cooker going enough to boil water. Need to read up on it some more. Thanks for the links. I'm looking at incinerating/composting toilets too.

 

[SHoggard]

It composts too

Agreed, to generate large volumes of gas from 2 people would probably involve insufferably long periods of incontinence.

But from what I see, it also takes kitchen scraps, garden cuttings... anything organic.... and acts sealed composter (so no smell form the compost heap), so the gas would just be an added by-product with compost being the main product - the human element would just be a contributing factor.

I'm not sure about incinerating toilets, but I don't think the impact on the air (& GHG ) would be too beneficial.

I'm also researching:
Greywater recycling & Rainwater Capture - you probably have similar thoughts also.

I'll be in Bali again 9-13 Jan - fancy a beer?

 

[mariaandrobert]

Drink one for us!

Thanks for the invite, as we always fancy beer! But, back to work for me tomorrow to pay for all of this dreaming. Enjoy your time in Bali! Hope its productive. We are too far (in New Mexico) to go often but usually go in early June every 2-3 yrs. We just keep hoping and praying for early retirement hence my need to get the next stage(s) of research underway.

Barring early retirement we probably have 4-5 years before we can supervise construction on the ground over there. Perhaps by then you and the others will have it all figured out for us and we'll have a viable and affordable plan with less work. Please keep us "posted". You already make me worry about my alang-alang, lol! Frankly, lightning had me more worried. Don't want to be Nekker island. Have to say in an earthquake I'd rather alang-alang fall down on me. So many considerations, huh? A fire-proofing preservative market, fake metallic alang-alang???

I understand all the organic material can be digested, even the yard waste and occassional unwanted household member. I still need the time to read up on this some more but am an otherwise busy procrastinator with dial-up. BTW a raw diet might benefit both ways, reduce gas consumption while increasing production. I reckon we've been cooking with dino poop for a long time.

Regards and Selamat Tahun Baru. Safe trip to the island.

 

[SHoggard]

Just one???

I can't quite figure out why, if you're installing a Septic tank why not take the extra step & do it as a biogas generator - yes the generator has a few pipes, lids. dials & taps, and is a 2 chamber unit.... but both use an anaerobic bacterial environment to do the job.

As for the alang alang, I'm not too worried, generations of Balanese have used alang alang for roofing, anyway when (if) it does disintegrate into powder... then the damn roof just goes into the biogas unit.