How to build a 200ltr biogas digester // DETAILED BUILD // free gas at home //

I am upgrading my 200ltr biogas digester and wanted to share the full build with you all. I go into detail about every aspect of the build, from start to finish. So if you are thinking about building your own biogas digester this is the perfect video to learn how.
Materials: (All PVC pipe came from - www.plasticpipeshop.co.uk/)
1.25m x 75mm PVC pipe
2.4m x 25mm PVC pipe
2.4m x 16mm PVC pipe
25cm x 63mm PVC pipe
50cm x 50mm PVC pipe
1 x 75mm to 63mm PVC reducer
1 x 63mm to 50mm PVC reducer
1 x 50mm Ball value tap
1 x 25mm T-piece
1 x 16mm T-piece
2 x 16mm End cap
1 x 63mm End cap
1 x 63mm Elbow
1 x 63mm threaded BSP adapter
1 x Barrel Adaptor 2" BSP - tinyurl.com/2hbhpyf6
1 x pot PVC cement
2 x 75mm Uniseal
2 x 25mm Uniseal
1 x 8mm Uniseal
Uniseal shop - tinyurl.com/3ahz75za
Chapters:
0:00 Intro
0:31 Materials
2:52 Uniseal fitting
6:42 Cutting the pipes
12:16 Fitting the pipes
14:18 Making the stirrer
16:00 Making the drain
18:24 Installing stirrer / drain
20:43 Fitting a new uniseal
21:54 Fitting the drain
22:49 Creating the base & install digester
23:43 Last few bits (bung & out-take)

[@IAMElectric369]

Suggestion 4-6’ feed pipe. Get rid of the bottom drain. You want a drain at the half way mark between the bottom and top of the fluid. This will be clear liquid fertilizer ready to use. Just use a wet vac to suck out solid build up in the bottom. All septics need to be vacuumed out at some point. You could put another drain n the side at the desired water level that comes out and dumps into another container(would probably need a vent valve). You can make that feeder tube as big as you want. I’d go 6 inch so you can really stuff some material in there and no need for a funnel when dumping in a slurry. I’ve been planning one myself and that’s what I’m doing. I think I’m also gonna use a second barrel to capture the gas in order to increase the amount of digestive material I can put into it. Add a pressure gauge and soap test your fittings since they’re not sealed with a sealant. I’m not crazy about the idea of those uniseals. I’d rather see something permanently sealed. Not tryin to tell you what to do, just sharing ideas. That’s how we improve. Lookin good tho. I’d love to see more people doing it. I thought about it years ago when I had a septic tank installed and Louisiana code required it to have an aerator(which I already have a fish tank air pump for mine) and a vent pipe that has to rise up above the roof line. I was lookin and that bell went off. I was like, holy crap, all I gotta do is cap off that vent and tap into it. Use a vacuum pump(an air compressor with a hose attached where the air filter is) and just suck the gas on outa there and into whatever storage container you use. Despite the logistics, it was a eureka moment, lol. Then I find out the Swedes have been doing it forever. Go figure.

[@macaddr2008]

Thank you for making the video. The explanation was detailed and very helpful. The function of stirrer is interesting. It was helpful to make a biogas system for my house.

[@RR-lv4kh]

Exactly what I was looking for🎉

[@janicekelsey]

Great details!

[@GetMeOffGrid_]

Glad you think so!

[@joshsundiwa]

Nice work, thanks for sharing

[@GetMeOffGrid_]

Thank you! Cheers!

[@marafikigreeninnovation]

Great video Thomas. Am building mine too

[@GetMeOffGrid_]

Good luck!

[@magoolajohn6475]

Thanks for your presentation

[@GetMeOffGrid_]

My pleasure

[@ManishKumar-xh8wf]

Fantastic bro👍

[@GetMeOffGrid_]

Thank you so much 😀

[@khachesowabuti]

I love your bicycle collection

[@GetMeOffGrid_]

Haha. Thanks!

[@simonem1587]

Thanks bro. U explain very well, l bless u and your generous behauvior. Simone

[@GetMeOffGrid_]

Thanks Simone!

[@janicekelsey]

Good changes.

[@GetMeOffGrid_]

Thanks!

[@christovanschalkwyk8214]

would like to see it in operation

[@pineastomas3791]

Good day. Thank you for the video. I built a similar digester here in Namibia but I have a challenge of gas leaking out between the universal seals and the pipe. Do you have any sealant to suggest?

[@UshanWijesekara]

A lefty like me well done

[@GetMeOffGrid_]

The best!

[@johnstewart1011]

Is the idea to use the pressure of the gas to push the fertilizers up the out pipe? how else will you fight gravity?

[@MultiOutdoorman]

Try removing all the burrs from the raw cuts and the pipes will give less trouble...

[@GetMeOffGrid_]

Very true. I found that out, after that a few micro-leaks in my seals

[@entomopathogenicfungus904]

I remember when I first discovered a deburring tool, ended up going round deburring everything I could find 😂 only about £10 for a good quality one

[@travisduck5339]

Very well done and explained, one question, do you have a problem with the gas line getting clogged up by the floating material ? I have seen that being an issuse for some people online, I see you are using a much bigger gas outlet pipe so I presume that is how you get around that, am I on the right track here ? I have seen other people just lower the outlet pipe to the side of the tank and have a constant gas bubble on the inside of the tank to get around this blocking problem. Please also explaine what the reasoning was for the smaller outlet pipe ? I'd love to know your thoughts on this, at first I would have thought the same size pipe as the inlet would be best but you obviosly have done your research and testing. Thanks for the video, again, really well done.

[@GetMeOffGrid_]

Hi Travis. I don't have much of an issue, main because I grind up all my food scraps etc before I put them into the digester. A design feature to also try and avoid this is the large diameter initial part of the gas outlet. As the end of this is way above the inlet level material shouldn't ever get to that height. So when it reaches the smaller gas pipe at the top there will be no chance of a blockage. As for the outlet pipe, the only stuff that comes out of this is the fully digested effluent. The volume of liquid that comes out of this will be equal to the volume that is put into the in-pipe. As this is never going to be a huge volume I decided that using the cheaper smaller diameter pipe and associated uniseal was an good design feature. The only thing that could happen is that the pressure builds up in the digester momentarily as the effluent escapes through the smaller pipe, I don't see this being a big issue though as feeding the digester is a slow process, even with a 75mm in-pipe.

[@travisduck5339]

@@GetMeOffGrid_ Thanks, I'm looking forward to building one following this design, looks great.

[@user-ju2zo3ld2x]

Suis très curie de savoir comment fabriquer le biogas dans le fut plastique de 200lts merci mes conduire pour avoir cette nouveau technologie

[@ncapp372]

hi enjoy your videos, do you use a spark arrestor on the gas pipe?

[@GetMeOffGrid_]

Thanks! No, I don't the gas isn't under any real pressure and there is nothing that could ignite a spark. So I am not too worried about it. Maybe I'm being careless, but I haven't seen others using one either.

[@mac660]

Great videos. Would you be able to put in links to where you get your materials from cheers.

[@GetMeOffGrid_]

Thanks. There are links for stuff that are quite specific, the uniseals and difficult to find adaptor. I've just added a link for the PVC pipe website. But its the same from everywhere. If you just search PVC pipe in google you can get the same types of thing. Cheers

[@douglaswindsor120]

Question do the barrels where you are at not come with a 3/4 inch threaded knock out in the middle of the bungs I've seen 2 other videos on biodigesters and a lot of us from north America ask why they didn't use them you at least used one of the bung holes with an adapter your bungs look like our old metal ones I'm going to build one with a couple of I bc totes I've finally found one that doesn't use uniseals and has a dome to catch the methane gas I was originally going to put them in series to get more gas production but one utuber said that would only get me about 10 to 20% of extra gas from the feeding and if I tried to feed it more it would give it a gut ache and Id probably have to start all over again he suggested parallel and feed them alternating days I'm looking at water pressure to pressurize my gas should be up and running by may

[@user-cm7rn9hd6f]

Hello Thomas, how do you utilise the biogas once it's made - I have a plastic drum similar to yours but it has a different seal at the top so I may have to use plastic cement to keep gas from escaping. I must truly commend you on making a video which as a girl, I can understand and try the best I can to make my own biogas digester. Thank you so much. Hope your video gets so many likes.

[@GetMeOffGrid_]

Thanks very much. I have not be able to make significant biogas in this digester as I had to leave the property where is was. I haven't been able to check if it has been productive yet. I am glad you find the videos interesting and useful. Cheers

[@kriskolassery4396]

Hi ,very interesting. Please 🙏 let us know how the final product has come out.i would like to build one .which part of the uk are u in.

[@GetMeOffGrid_]

I am in the south, in Hampshire.

[@LK-hl3hv]

👏👏👏

[@GetMeOffGrid_]

Thanks 🙏

[@SimpleEarthSelfReliance]

Very nice. I came here after watching your water heater stuff, and went down this rabbit hole of useful builds from a realistic human being. I appreciate your style and honesty. It's awesome. Keep it up man. Regards

[@GetMeOffGrid_]

Cheers! Really appreciate it.

[@nzirimugodfrey1614]

Great work, how much gas does the Biodigester in the summer? Just built one but the gas does last more than 20 minutes

[@GetMeOffGrid_]

Really depends on the climate in your region, how big your digester is and what you are feeding it. If it is producing gas but not a lot then it could be the temperature of the digester (ideally 30-40 degree C) or the amount of food you are feeding it. Be careful not to over feed with vegetables as it will acidify

[@itanc1]

Hey dood! Loving your work. I need to build at least 2 digesters plus ancillaries, is this design working for you and would you suggest it as a good one to replicate? It occurred to me ( also a rocket heater evangelist ) that it might be better to use the flammable gas that you are making to heat the digester. If the AD is fantastically insulated then once up to temp it will behave as a flywheel and require a small amount of gas to maintain. 5v igniters are very effective and cheap and coupled with a passive thermostatically controlled valve you could use a small amount of your methane to avoid the need for another rocket heater. My concern with a rocket heater is that it would be overkill and risk being an uneconomic use of energy? Anyway, would love to start a conversation about it all, where about are you based? Cheers. Tanc

[@GetMeOffGrid_]

Hey! Thanks very much. I am playing with this design as its easier to change about that a larger one. If I was going to really use this at a household level I would use an IBC. Once I get this going as I would like and have all my monitoring system in I will move to the next stage. Yes the idea of using the gas to heat the digester has occured to me, but as you mentioned it would have to be very well insulated to be efficient. Rocket heater is a nice idea but I think its a bit of overkill and also requires too much manual intervention / complex setup to make automatic. I am in the south of the UK. You?

[@itanc1]

@@GetMeOffGrid_ , I’m in Newport, South Wales. I have seen digesters that are buried which obviously saves space ( a big plus for us urban off gridders) but also opens the door for super insulation. You could did a big hole and line it with a healthy amount of straw and maybe use a solar panel and reptile heat mat with control from the rpi or Arduino. Simple and reliable? One thing I have learned from my work on small scale induction melting is that really good insulation has an astounding effect. Maybe an overground ibc could contain a fat layer of straw around your barrel. I agree that the rocket heater is not really going to be your friend here due to as you say too much intervention required. When you get to the point of knowing how much food produces how much gas in how much time, I would be really keen to know? I’m also keen to get the gas purified enough to use as a road fuel, which as I understand means dissolving all the co2 and h2s out to produce pure methane. Do you have means to analyse the gas produced. Lastly can you tell me the composition of the effluent fertiliser that is produced and have you used it to grow anything yet? Oh and do you know about biochar? Cheers Tanc

[@blunderworld3012]

Have you guys thought about a Sand Battery to heat the digester?, or a least to maintain a steady ambient temp around it?, I'm building a system using a 1000 litre IBC inside my greenhouse but I'm also looking at the possibility of having a sand battery below the IBC.

[@itanc1]

@@blunderworld3012 hey Dood. Love the sand battery concept. The issue I can see is that effective sand batteries run at 500 Celsius or more and the AD needs to be kept at 35 so a temperature regulator needs to be used. Maybe thermostatic radiator valve would do otherwise it’s another job for the raspberry pi. On the point of temperature within an AD I have found that thermal stratification happens and you end up with the bottom being too cold and the top being too hot. This only the middle actually produces methane. This is why commercial plants use CSTR systems ( continually stirred tank reactors ). I have prototyped a control system that uses 5 sensors at intervals from the bottom of the reactor to the the top and if there is more than 1 deg difference it turns on the stirrer until the temperature has evened out. This uses ds18b20 sensors (1 wire for as many as you want) and a RPI running a simple python script. This will still work whatever heat source you use. My system is a 200 lt drum which is very well insulated with 2 complete layers of 30mm PIR insulation made from wedge strips and carefully taped together. On one occasion I accidentally overheated it and it took 4 days to cool down again. Another favourite for heating is solar powered 24v 3d printer bed heater but I don’t know how many panels one would need to last the winter and for this reason the inter seasonal sand battery is a hot contender. This could also be heated from solar over the summer but again I don’t know the numbers regarding number of panels and volume of sand. You could check out Robert Murray Smith he does enormous KZbin work on alternative energy and is always happy to chat. Hope this helps and feel free to stay in touch as I am always keen to connect with AD people. All the best. Tanc

[@blunderworld3012]

@@itanc1 Hi, many thanks, I've just started with this digester idea, you give some good info/ideas there, I've subbed to your channel.

[@AboveGroundLevel.]

Really informative video on making a small biogas setup. Could I ask where you store the gas? Do you have a separate floating storage container or inner tube style? If you were to upscale this to an IBC container is there anything you would consider changing. Really interesting concept to play with given the current climate. Subscribed and would really appreciate any future updates / changes to the system in the coming months. Thank you kindly for posting a detailed video. ATB

[@GetMeOffGrid_]

Thanks very much. I have a 1m3 gas bag that I use for storage. I am also intending to compress the gas into bottles for long-term storage. I am hoping to get a solar heating system setup in the next month or so, so stay tuned for that.

[@AboveGroundLevel.]

@@GetMeOffGrid_ awesome. Look forward to future updates with his concept. I currently live south UK. You couldn't point me in the right direction for one of these bags as eBay / Amazon don't sell any kind. You haven't got a spare for sale by any chance 😃

[@extramedium8074]

Hi mate. Really enjoy your content. I am also thinking of building myself a bio gas digester. Just wanted to know what your views are if its still worth it not specially in UK where weather is not very favourable? Also, I havent seen a video where you have shown how the rocket stove is working alongside your bio gas digester? Thank you

[@GetMeOffGrid_]

To be honest, I don't think it is worth it. I haven't got to a system that produces methane reliably in my setting. I am going to give it another go this year, but if I can't get it to produce significant methane, I will call it. I decided not to use the rocket stove as the kind of stove I am using, manually fed, couldn't do what I wanted without a lot more engineering. In theory, it could work, but if you are going to give it a go, a well-insulated, solar-powered heater is probably where the sweet spot is in terms of engineering, effectiveness and efficiency. Cheers

[@palesabontle1270]

Great video! How do we remove Co2 and H2s from this digester?

[@GetMeOffGrid_]

Thanks. Check out this video I made a while ago about this process: kzbin.info/www/bejne/pYrYdXygnLOLrLM. I also made this one a bit more recently when I upgraded my scrubbers with more durable material: kzbin.info/www/bejne/m6etn4yGj8iLfpY

[@palesabontle1270]

@@GetMeOffGrid_ thank you

[@NoToPCBS]

How much gas does it produce in 24 hours? Thanks

[@DylanDraper1]

I want to see this operate an instant water heater

[@phillipthurston2562]

I'd love to see it put on an furnace.

[@misbauddinchowdhury2180]

is 200ltr digester enough for cooking? I think the production of gas is not enough for cooking. Could you please suggest how can I make a digester which gas can be used for cooking?

[@GetMeOffGrid_]

You could make it bigger if you are worried it won't produce enough

[@Shortsdailyvideo]

Hi...200ltr is enough for small household like 3person?

[@GetMeOffGrid_]

Probably not. I only did a 200ltr to try and work out the process. I'd use a 1000ltr IBC if you were doing it for a household above 2 people.

[@pranjalgarg3106]

Sir, don’t it leaks?? Have it is tightly packed?

[@GetMeOffGrid_]

No

[@kingfrank6877]

Please looking for a list of scrubbers where can I buy them any links

[@GetMeOffGrid_]

You'll have to make them.

[@kingfrank6877]

@@GetMeOffGrid_ can you send me a list of what I need please

[@GetMeOffGrid_]

I have made two videos on how to make them. It will depend on what is available where you are, if you watch the videos you will hopefully see what you will need and then be able to find things that are similar where you are. Good luck.

[@barkatalimagsi8744]

Hi, bro I made a Biogas digester but unfortunately gas is not coming why? I used animal manure with water 1:1 What is the reason can you explain some factors?

[@GetMeOffGrid_]

A couple of things come to mind straight away 1) what type of animal manure 2) how long have you waited? 3) What climate are you in?

[@barkatalimagsi8744]

@@GetMeOffGrid_ cow dung, temp is about 40 to 50c . It has been 35 days . Smell of gas is coming but when we burn it does not working. However waste is coming out from the digester. So what should I do to get gas?

[@walkingchantv5936]

What the name of that black color the circle one

[@GetMeOffGrid_]

It's a Uniseal. 👍

[@xochipili1]

Not feeling the bottom drain.

[@eastcoastnews9529]

How much burn 🔥 time do you get out of it once the Bacteria gets going ???

[@GetMeOffGrid_]

It really depends on the type of thing you are feeding it with. If you keep topping it up with manure then it will be more productive.

[@user-qo5kl8ey5w]

please make a final vedio based on your experience and demonstrate it on white board

[@GetMeOffGrid_]

Maybe one day

[@gabrieliosipescu712]

what happend with surplus gas ?

[@GetMeOffGrid_]

Not sure what you mean? The surplus gas is what we want, its what is collected in the blue gas bag.

[@scofishcheiman5267]

Eden hazard

[@markhindle5243]

did it work

[@GetMeOffGrid_]

I'm filling it this weekend, so we will see in a few weeks

[@TuTuNaNa-007]

If we use cow dunk mixed with water How much burn time we will get ?

[@aprilatas9832]

Can I have a blue print

[@GetMeOffGrid_]

I don't have one at the moment. I would hope that from the detailed video, you might be able to make one yourself. I will work on putting one together and release it via the community pages when I do.

[@user-ug4cp5nl9d]

Too complex please simplify

[@GetMeOffGrid_]

Enjoy life, if you think this is complex

[@MohAwad-mw2oz]

..yes yess stop..how long..how deep become the pipe's !??

[@an_what]

Just so you know that's Teflon tape and you're not supposed to spool it off like that you supposed to pull it in the opposite direction that way you pull it tight I don't spool it off like a roll of tape it should be reverse

[@GetMeOffGrid_]

Cheers