CHP project for my small farm in Norway

Hi to all of you experienced builders, I have a smal farm here in the midle of Norway.
The plan is to implement a CHP system using wood chips from my forest and the surrounding fields.
As for the timeframe I do not have anything set in stone but I give my self a year to have a smal container CHP, and then another year for a inhouse automated CHP room in the barn, to heat workshop, other rooms in the barn, chicken coop, house with hot water tank and as a bonus if possible heat and CO2 for the greenhouse,

Im going to update this frontpage with the best solutions at current date. (bare in mind my english skils and spelling)

Now for the plans and ideas. (all input and dicussions are welcomed)

Housing for the first CHP is a 10by10 foot
Container pod, a little insulated (10cm glasswool) plywood roof and walls. (might get fireproofed later)

The gasification unit and powerunit

I like the GEKTOTTI design, the way the gas flow on the outside of the inner chamber to preheat injected air sound like a good idea to me, Im not going to mess around with waterinjection until i fully understand how that work. Everything is going to be insulated from the surrounding environment eventually, not only to prevent overheating in the small pod but also to keep the energy where its intended to be.
Exhaust gases from the gasifier is going to preheat and dry the woodchips until desired temperature for combustion (not shure what the desired temperature is).
Storage for weekly (or as long as possible ) buffer of woodchips is going to be on top of the pod, its easy for me to load it there in the begining with the frontloader of the Valmet tractor and the big snowshowel.
This is what Ill use as a feed screw on the roof.

Eventualy I hope to have a double perforated floor on the top of the pod to dry the biomas with left over heat and forced air.
The gasifier

Hopper material

Motor and generator
The motors im going to use in the beginning are B20 Volvo engines, the reason for this is simply that they are simple motors, relatively low rpm, not picky on the fuel, easy to adjust timing and I already have two of them here on the farm. Also very cheap parts.


As for the generator
I think asyncronus motor is the easy way to go for grid tie, start the B20, get the RPM to the rated rpms of the generator, flip the braker to synk the grid and motor and then increase the RPMs about 10 RPM over rated of the generator (amp supervision to decide when you have reached rated amps)

I have not decided yet on the type of electronic supervision, it might be a hybrid solution of arduino, raspberry and Siemens PLC.

Heat storage

Idealy all of the heat generated by the B20 motor and gasification is to be used in one way or another.
All cooling fluids of the B20 motor is going to be heat exchanged against a 5000L buffertank, maximum 95 deg. C
High manifold temperatures in the botom of the tank where the water is coldest, left over eccess heat to be used to dry the biomas, the now cooler exhaust gases to be sent in the greenhouse for CO2 and heat. (filtered and not to be used when people are inside)

So this is the plan, all input and ideas are welcomed.
Ill update with pictures and video as I go.



Roger you are just going to LOVE this site… Welcome. I’ll let others steer you to the right design for your needs.

Hello Roger,

it does not have to be… if you set up your system as follows: gasifier-engine-generator-rectifier-hybrid inverter
This makes it possible to run on different RPM’s , lower when not to much energy needed, higher when more energy needed, and the syncing with the grid is painless.
On the same inverter you can install some solar panels and a battery pack as well.
Voila, system “almost” perfect…


re-reading it you are certainly thinking big. When my work designs for home power systems the first thing we always ask is how many kW Hrs do you use in a day?
It matters because most of the gasifiers you will see posted except for the commercial units are batch types. For your situation I think Koen is right you would end up incorporating a battery bank, a hybrid grid tied inverter and use the gasifier to keep that bank full. The battery is a buffer, and you run the gasifier as many hours as you need or want. Spin the meter backwards to equal your consumption. Its a tried and true model that utilities have grown used to by now. We install the Radian series from Outback Power. Schneider and Sunnyboy both have their own equivalent.


Hi guys, thank you for the warm welcome.

I had hoped to avoid using a batterybank as it is costly, my hope was to produce to the grid as i run the generator.

This is what I use from the grid to day.
kWh on the left and temperatures shown on the right.

That is real nice graphing they provide for you. Can you click on the daily usage page and show that. This screen is instantaneous usage I think. Daily totals would work better. Also the battery bank does not have to be big for grid tied systems since its only acting as a buffer to balance out the system unless you want some power outage capability but that gets expensive.
Thanks, David

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Here is the graph for a above average day of consumption when its under -12 deg C

What about transmittion loss when you run the power through a batterybank compared to directly from the asyncrongenerator?
I do like the idea of a battery buffer, and it might be that a crashed Nissan Leaf fall in my lap, its just that the asyncrongenerator is self syncronising to the grid, you dont need any converter or inverter to start producing power.

Does your utility even allow that? It’s all but illegal here except for industrial producers with much higher insurance then most homeowners. If you were charging batteries and discharging them then there would be losses but just using it to regulate highs and lows they should be minimal. It depends on the level of complexity you are comfortable. I’m at the edge of my knowledge here so don’t take my word for it.
Cheers, David Baillie

It is not that easy in some parts of the world, at least. Sure, it’s easy to do, but as far as I can tell, very few electric utilities will allow that sort of device without a lot of expensive “safety and control” equipment between your generator and the utility. They ALWAYS play the lineman safety card first. Why not? It doesn’t cost them anything to say “NO”.
If I were you, the very first thing that I would do is to sit down with the utility representative and find out what restrictions they have in place and work backwards from there to determine how to please them enough to allow you to connect.
In my state of Wisconsin, USA, in my utility, they simply say things like: “sure, you can connect, but you must use UL approved devices”. That really means “NO” to almost any sort of DIY setup.
I built a 12 HP device like that over 10 years ago with grid tie plans similar to yours.
In addition to all the regulatory pitfalls, you have to deal with power factor by adding a lot of capacitance on the line or your output efficiency looks terrible.
A guy in a neighboring state was getting away with it in a very rural setting, but I am not so far “out of town”.
Maybe things are a lot different in Norway.

If you don’t already own this book:

you should get a copy.
SEIG (Self Excited Induction Motor) is a buzzword for this sort of thing.

Pete Stanaitis

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I have a friend that used to do this. He has a big farm and uses lots of electricity. He gad a woodgas 1,2l engine and a electromotor connected on it, then he started it all up, connected to the grid and “overspun it”, like Roger describes it. The resault was a constant load on the engine and the “electricity meter” spining slower, or eaven backwards. Ilegal? You bet. But it worked And was wery simple. At the time those meters were mechanical. Not sure how this wukd work on todays electronic meters…

As for talking sencefully to the power company in connecting your powerplant to the grid, its a war lost. Papers, inspectors, standards, taxes, papers, papers… just not worth on a small scale. At keast not here


Reading a little bit about it norway has tonnes of grid connected solar so obviously the authorities would go for it if you use a grid tied inverter as a go between. You simply choose a grid connected inverter with a voltage range equal to your battery bank and feed the power back that way all nice and legal common off the shelf equipment. 48 volt grid tied inverters used to be common. Sunnyboy is very popular in Europe and with a strong solar industry they should be available second hand as well…


The powercompany support all power thats produced out in farm land since it helps to keep the voltage up and make the grid more sturdy. If you use a asyncrongenerator it cant produce power by it self, it need to be magnetised. Since im going to let the grid magnetise my generator its not going to produce power if the grid fall out, meaning its relatively safe.
Yes im going to have a meeting with the powercompany about this (I know a few guys there)
Im not so good at explaning but here is two videos that can explain what I mean.

and one of the drizzler guys

I just remembered— I think if you do add power factor correction capacitance, then the generator may become self excited
This might be worth mentioning to your friend at the electric company.
Pete Stanaitis

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Yes you might be right about that Pete, I know there is sensing equipment on the market to supervise the grid for safe shutdown, aka the main contactor cut the generator of.

I would still suggest converting to DC and using a solar inverter to push the power back in the grid for grid attached solar. There are 2 advantages to this first your interface to the grid is an off the shelf product which protects you from the power company issues. The second benefit is that a generator running on wood gas might be hard to keep stable enough to run directly into the grid. The voltage and frequency needs to be within a tight tolerance. This might be difficult for a home built gasifier I would expect the amount of gas supplied by the gasifier to the generator wouldn’t be stable enough. Retificting to DC and using a solar inverter would avoid any issues about how stable the generator is or if the motor is running at the correct speed to match your grid frequency and voltage. I think the added cost would pay off once you start running the system. It will just be much easier to run.


imagine you are connected to the grid without any “regulator/interruptus” what happens if the utility have a dip ?
or when you’r sending power into the grid and it gets disrupted some mileage from your home, but not between you and the nearest village…
Hence the hybrid converter… if the grid goes down, you still have power… be it from solar, generator or battery’s…

Food for thinking, install a little bigger generator on your vehicle, charging a battpack in your trunk, use the power from the battpack when you’r arriving home… charging the battpack on a fraction of the normal cost…

Use your car to provide heat and power to your house as well… drive the car on a gasifier… connect heat, exhaust and generator to your home and offgrid you are… ( exhaust heating a big tank in your house can be done )


I have the GEK . It was a huge mistake . 20 kw grid tie with version 4 gasifier . allpower labs will not provide support .
Gassifier had leak in corrugated tube for air pre heat . governor was unreliable and failed and was replaced .
4 cylinder engine has sticking valves and will barely run .
Last year i tried using wood gas boiler to power generator . got gas flare but engine failed to start .
have solar 5kw 25 mwh produced grid tied . power company does not allow the grid tie .I put in battery bank with outback radian inverter that is now allowed to grid tie power from gek , Gek is broken .

Hej Roger. Välkommen till DOW!
I’m with you here. I don’t see a problem running an asyncron motor. The grid won’t notice if the motor is pulling or pushing power. Only your meter will.
If the grid goes down the same thing will happen as if you had only a flywheel attached to the electric motor. Just see to that the B20 doesn’t start reving itself to death if the grid “load” disappears. Apart from that you won’t need a governor.


I should have gotten version 5 with grid tie . will you have ash auger and ash can ?
I have to open unit to remove ash . power produced by unit is not worth having to replace this gasket so frequently.