You are right, Tone. That’s what they declare. Those 7 MWh are together with heat output in CHP mode. But still, its not 80% efficiency.
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True Tone. They “fudge” their claims by quoting only gasifier sub-system system energy conversion for that number.
Mr Veljko it is well worth reading and studying two peer reviewed publications put up here in the DOW Library section.
Go to the top tool bar Library. Once opened up scroll down to the “Gasifier theory and operation” section.
Download, and read study both:
“World bank Tech Paper #296” and
“FOA 72”
Different reasons each organization developed these conclusions. The World bank decided that while village-community bio-mass gasification power systems were technically possible the combination of social factors, outside sourced high-techs single points failures, world market up/down available petroleum energy sources made financing these a no-go for them.
The UN Food and Agriculture was more optimistic. But even they could only find two longterm community/schools continued in-use systems that were locally supported ongoing. One an island religious school. The other an in Uruguay? Religious community in their logging mill operation.
(I may mixup which publication said what. No matter. Only conclusions matter. Study both.)
The diffnert largish scale gasifier systems were measured as ~72% energy efficient. Using a BTU/Calorie basis for the made fuel gasses.
Now turning that into engine shaft power, then into electricity overall: the wood-mass to useable electric was in the low 20% ranges.
Considered actually good in comparison to equivalent sized steam systems. Even petroleum fueled systems.
With the age of these paper PV solar was not studied. Neither was the newer battery storage systems.
These work. But more $$,$$$ or whatever capital, to have to pre-invest into. With even more technical specialist dependencies. Certainly more choke-point, 1st world hardware dependencies.
I agree with Marat’s opinion on each household as a separate self-producer and user. Now that to build could be scale cost reduced by manufacturing a same-same base model system.
And then when the Power-That-May-Be try to tax, regulate or even shut down trying to force their supplied instead they would have a much more difficult job of it.
Social it will only work if you can collect up individual member households with a core ethic of defending their own personal freedom and independence right down to the last bullet.
Maybe this is possible in Serbia.
It has proven possible in other places of the world in the past, and the present. Improve your odds by locating up in the terrains of mountains. Or bogs and swamps. Desirable flat land, and flatlanders too often just get rolled up and placed in someone else’s pocket. Under someone else’s thumb. Think. Live the ethics of these poor-landers folk. Be Swiss. US Appalachian/Cascade mountains hills-folk. The different south central Asia mountains peoples.
S.U.
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Me thinks Mr. Veljko left the conversation about 10 days ago, so we are preaching to the choir again, amongst ourselves. Comments, @mveljko78 ? 
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I’m here 
I think there are two options
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modest one. Power for lights laptops and Internet provided by a gasifier running for 8 hours every day during winter. Solar in summer. Supplemented by gasifier on cloudy days.
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luxurious variant. Small hydropower turbine on a nearby stream. Running freezers and refrigerators by compressed air. Providing power for laptops lights and internet. Gasifier only as a backup option, and for more laborious tasks - sawing wood, mixing concrete etc…Turning on gasifier on demand
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I’m not familiar with running refrigeration with compress air. Until you have tried to run a gasifier and generator for 8 hours a day you will not realize how much effort that requires. However with a good battery system it would not really be necessary. I can comment on what is involved with operating a wood gas fueled generator but have not gotten into battery back-up yet to know how many hours it would take to keep a battery bank happily charged. If you can get the electrical load required for refrigeration out of the equation the powering lights and and other lighter loads would not be a problem. As you mentioned, larger chores could be done on demand.
I believe there was a member here who was getting hydroelectric power seasonally from a small stream fed turbine. I’m not sure if he detailed it’s operation or not. He was from Oregon and now I have forgotten his name. A lot of things can be run on compressed air but it takes a lot of it. I have wondered if a water pumping windmill would have enough torque to run a decent size air pump. Anyway, any effort to free yourself from the grid, supermarkets, outside control is a blow against the empire and I’m pulling for you.
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To me it seems that a charcoal gasifier would be appropriate. I was surprised at how easy it was to make an engine run the first time I tried to do it. I studied Some school in Thailand. I think that one 55 gallon (200 liter) barrel of charcoal and one simple updraft gasifier should not be unreasonable to have at each of 10-20 houses. Charcoal does not rot or degrade with time, so in some ways this is easier than maintaining a supply of gasoline (petrol). Perhaps the 10-20 houses can share one charcoal maker.
Rindert
My tlud (Top Lit Up Draft) charcoal maker.
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Good! I thought we were annoying, and drove you to some other forum!
If you have access to a stream with enough flow and/or elevation difference, that might be the first thing to harness. (permanent magnet rotor+ wire wound stator connected as a dc battery charger).
So many questions I have! do you have any exposed and windy places for a home-built wind generator? Are your dwellings going to be close together for easy sharing of utilities, or like a group of mini-homesteads, separated by a greater distance? (much more wire, pipe, etc.) you may just have to begin construction and see where practicality leads you!
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That is not luxurious, that is basic energy available more reliant then the sun! Wow, good for you, but forget compressed air. That way you only make heat instead of power. Small electric turbines are available. Batt bank can be smaller and also you pv array. Does the stream freeze in winter?
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I was thinking about this - using compressed air to refrigerate food.
Not sure if the stream freezes - we are still searching for a suitable place. But that’s an important think to ask locals when buying.
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Low tech and robust ok, but also low efficiecy. If you make calculations for real life I dont think it will make a chance.
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The idea is to avoid converting hydropower to electricity and then run freezer or refrigerator. Instead
hydropower can run air compressor and when compressed air is released into the freezer it will cool. Like when you open propane valve it will freeze.
But, it may be that refrigerating fluid in modern refrigerators is more suitable for the task, and even when loss of energy when converting from hydro to electricity is taken into account, it may be still more efficient to use electricity. Who knows… We will have to find someone qualified engineer to make a couple experiments and /or calculations
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Hydro power plant, windmill with mast, solar panels, chemical batteries, converters, battery chargers, wires, pipes, etc. And in order not to sit idle, you can still add a compressor, cylinders and pipes for air! 
Will it ever pay off at all? Using such complex systems, is it possible to earn money working as a welder, miller and turner?
I wouldn’t want to be an engineer in a settlement that needs to maintain this every day at any time of the year…
Why do people still not like leaves as solar energy converters and wood as solar energy accumulators??? Only by the fact that there are still no converters of this energy into 10-20 kW of electricity with an accompanying amount of heat, and sufficient durability of the installation?
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paying off and money is now not an issue Serbia being in Europe, we are certain that at some moment electricity will go off due to war or side effects of war. At least supply wont be stable …
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In this case, you should not be interested in electricity for refrigerators and freezers, but in ways to grow food and preserve it, preferably without refrigerators and freezers, for example, stews and cheeses made from milk.
And the fact that firewood is the only civilian fuel during the war was clearly shown by Europe during WWII. Do not waste your energy on high-tech technologies that are not available in times of crisis and war.
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Marat, I dont want to argue with you because I think you are a very, very wise man. WW2 showed a lot. The big difference with the present is the cheap available PV. If the waste bothers you, buy it second hand and help not wasting wast 
. It will still outlive you and hopefully some of your children.
Waterturbine can still be lowtech.
Nothing beats a simple humble life, respect. I really do, says the pizza eating couchpotato.
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That was a very interesting article Veljko. At one time I worked supervising the installation of automotive paint systems. We used a lot of air motors to avoid the possibility of a spark from electric motors. This was in large auto plants and a massive amount of compressed air was required to run tools as well. Scaling any of this down is problematic but not necessarily impossible. At one time I had a compressor in my shop that would produce 24 CFM. I was run by an IC engine. It produced a lot of heat between the pump and storage tank and required a cooler. I never got a chance to explore how that heat could be put to better use before I burned that shop up. Since you have not yet purchased land and you are willing to go into the wilderness I would make it my first priority to find a location suitable for hydro power. I am not opposed to PV but it also has limitations that will become more drastic in days to come. Even where I live we can go for weeks on end without seeing direct sunlight due to the moisture from the Great Lakes. I don’t think anyone is trying to discourage any of your efforts. Just wanting you to go into it with eyes wide open.
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Complexity and availability would be my guiding principles here. If I had a small hydro electric source to trickle power to a battery I would go straight electric with a solar array and a gasifier for backup with some way of capturing heat. Perhaps air powered machines and more importantly people to install, service and maintain them are common where you are but here the driving force is a lack of qualified people. So in my world it makes more sense to invest in a well engineered off the shelf solution with a proven track record and a service infrastructure behind it rather than create a technology suite from scratch because it might be more sustainable long term. If you are building a community from scratch you will have enough to keep you busy without recreating everything. My two cents
Cheers, David Baillie
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Here is a relatively low tech way to make compressed air directly from falling water.
Rindert
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More then the things said is what Marat pointed at. The basics. My kind of bible, The Good Life from Helen and Scott Nearing. When purchasing a landplot, the first thing was drink water. Still the most important thing. If it streams you get energy also. Before that comes good soil.
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It is easy to become wise if you live in a place where there has been a war for 9 years, and you do not run to where there is no war, but instead you are looking for an answer to the question: what to do?
Relying on a hydro turbine will drastically reduce the options for choosing a place of residence. And, right away! Moreover, the sacrifices for the sake of this source of energy may subsequently be huge, and the source itself may eventually dry out or become banned. 
Behind the beautiful abbreviation PV lies a real horror: the limited charge-discharge cycles of batteries (from 400 to 1200 for lead, and up to 3000 for new lithium), short circuits of some battery cells, power electronics of a powerful DC-to-AC converter, controller malfunctions battery charge, failures in the lithium cell balancing system, lack of sun, especially in winter, etc. And all this will take place in the realities of war, when none of this nearby can be obtained, bought, or brought …
At the same time, cars without fuel are usually worth nothing. And many of them can be damaged, as was the case in Mariupol and other Ukrainian cities. In this case, the internal combustion engine can remain intact or be a donor of spare parts. Not every abandoned house has surviving photovoltaic systems.
I am not a supporter of the apocalypse, but it looks like the war will go on for a long time, because there are still a lot of resources for it, and its real goals, hidden from people, are terrible in nature, and have not yet been achieved.
I vote for a comprehensive and integrated approach to solving the problem of “where and how to live”! And not just for beautifully advertised temporary solutions with a bunch of pitfalls. Different conditions of peace and war dictate different concepts of the beauty of the energy supply system. Coal dust on hands in peacetime looks ugly, but the electric light from the same charcoal in wartime glows with magic in the darkness.
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