Wood gasifier for a greenhouse
Load wood chips in the evening — warm till morning
I will teach you to build it yourself: drawings for your greenhouse, assembly, first start.
In the evening you fill the 250-litre hopper with wood chips. That is enough for a whole frosty night in a 100 m² greenhouse.
Gasifier in the greenhouse
Power adjusts by itself from 10 to 100 %. The controller speeds the fan up or slows it down. No need to get up at night.
The gasifier stands right inside the greenhouse. Heat from its walls and pipes stays inside, so it burns up to 30 % less fuel than a wood stove.
It runs on wood chips, not logs: branches, garden prunings, sawmill waste. Pieces up to 5 cm.
Gas from the chips goes through a pipe into the boiler and burns with a blue flame, like a kitchen gas stove. All the heat stays in the greenhouse.
Along with heat, the plants get carbon dioxide. It feeds them, more on this below.
Your local welder builds it. I make the drawings for your greenhouse and your fuel.
I am in touch and will help you at every step.
Message me on Telegram: the size of your greenhouse and how you heat it now. I will tell you if a gasifier suits you.
Calculate your greenhouse
Pick your greenhouse. The calculator shows right away how much fuel a wood stove and a gasifier would use in a season.
Split firewood usually costs $60–130 per stacked cubic metre. Enter the price you pay where you live.
Per season
On the coldest day
One unit with a 250-litre hopper keeps such a greenhouse warm all night. For the first winter, keep your old stove as a backup for the hardest frosts.
How we calculated
- Heat loss: 1.7 × area × the covering’s heat-transfer coefficient × the temperature difference. Covering: 1-layer film 6.5; 2-layer film 4.0; polycarbonate 3.8. We keep +10 °C inside.
- During the heating season we heat 16 hours a day (the sun warms the greenhouse in the daytime) at the “usual night” temperature.
- Dry chips and firewood give about 3,500 kcal per kilogram. A wood stove gives the greenhouse about 55 % of the heat: smoke and hot gas go up the chimney.
- The gasifier stands in the greenhouse, and heat from its walls, pipes and exhaust stays inside. The estimate is careful: 30 % less fuel than a stove (we say “up to 30 %”).
- A stacked cubic metre of split firewood is about 450 kg.
- Your own prunings and chips count as free. Time for collecting and drying is not included.
- Only your greenhouse will show the exact use. Sergey will calculate it with you in a chat.
Why plants need carbon dioxide
Plants build themselves from carbon dioxide and light. Outdoor air has about 420 parts per million, and commercial greenhouses keep twice as much. A gasifier gives it together with heat.
parts per million is the norm for tomatoes, cucumbers and peppers; outdoor air has about 400
Ontario Ministry of Agriculture, Canadabigger harvest with CO₂ feeding — according to a maker of such wood-chip units
Hot Lime Labs, New Zealandof its tomato crop was lost by a 12 ha farm when it ran out of purchased carbon dioxide in 2022
Grower2Grower, New ZealandSee how it works
Sergey’s videos (in Russian) about gasifiers in greenhouses. Tap to open YouTube.
700 m² of greenhouses in winter: a gasifier and a fan of only 0.55 kW running at low speed.
The owner of a 700 m² greenhouse removed a 70 kW pellet burner that could not cope and now heats with a gasifier: waste and rubbish mixed.
Why a simple wood stove is a poor choice. A gasifier gives heat, electricity from a generator, carbon dioxide for plants and charcoal for the beds.
Why plants need carbon dioxide, why greenhouses around the world lack it, and how a gasifier gives it together with heat.
A look at a European greenhouse unit: how it works and why our simple way is more affordable.
