Electricity from wood

How does a biomass cogeneration

plant work?

Electricity from woodHow does a biomass cogeneration plant work?

Biomass cogeneration plants that use solid, renewable fuels such as wood pellets, wood chips or wood briquettes not only save costs, but also make an important contribution to climate protection - around the clock. How does such a biomass cogeneration plant work? You can find out here.

Companies all over the world are facing major challenges: To meet climate targets while reducing price risks, they must fundamentally transform their energy supply – away from fossil fuels and toward renewable energies.

A climate-friendly and at the same time highly economical solution is provided by combined heat and power plants (CHP) that are operated with wood-based biomass – e.g. with wood pellets, wood chips or wood briquettes (in short: wood-fired power generation).

By combining electricity and heat generation, such biomass CHP units achieve higher efficiency than many other energy technologies. Operators therefore not only save CO2, but also cash. In addition, biomass is the only renewable energy source that can provide energy all year round, regardless of the weather or time of day.

Table of Contents:

How does a biomass CHP unit work, using wood-fired power generation as an example? This is what a biomass CHP for wood conversion can do. For whom is wood-fired power generation worthwhile? For whom is wood-fired power generation worthwhile? Wood gas and biomass cogeneration plant: advantages at a glance. Wood gas and biomass cogeneration plant: advantages at a glance.
Which fuels are suitable for wood-fired power generation? How much does a biomass CHP unit for wood-fired power generation cost? Environmental friendliness is rewarded: subsidies for wood-fired power generation plants.

How does a biomass CHP unit work

using wood-fired power generation as an example?

How does a biomass CHP unit work using wood-fired power generation as an example?

Basically, a combined heat and power plant (CHP) is a power plant in which heat is generated and used in addition to electricity. CHP units mainly consist of an internal combustion engine that uses either liquid or gaseous fuels and drives a generator to produce electricity with the energy generated.

In contrast to a pure motor CHP unit, which is usually operated with fossil fuels such as natural gas, diesel or similar, a biomass CHP unit is a plant that can generate electricity and heat simultaneously from a solid fuel (the biomass). This first requires the conversion of the solid biomass into a so-called syngas. This process happens in a gasifier. In the case of wood as biomass, lean gas is also called wood gas.

Woody residues are mostly used as wood biomass. For example, residual wood, waste wood, damaged wood, dead wood or production residues. These materials enter the wood gasifier processed either in the form of pellets, wood chips or wood briquettes. In the gasification process, the substances are carbonized under lack of air, so that a combustible gas is produced.

Following the wood gasification, gas cleaning and cooling takes place so that the wood gas is suitable for use in the gas engine of the biomass CHP unit.

Technology of the 50 kWel plants

Wood gas generation Carburetor Wood gas is freed from ash Heat Exchanger Wood gas cooling Ash discharge Ash is discharged from the system Engine Wood gas is burned in the engine Heat Exchanger Heat recovery from exhaust gas Generator Power generation Control Cabinet

Technology of the Plants with ≥ 135 kW Units

Fuel Supply The wood chips are fed into our system via a screw conveyor. 3-part wood carburetor Our carburetor has tested tech-nology, which guarantees stable operation, low maintenance and long service life. Double tube The syngas from the gasification process is fed to our hot gas filter. Hot gas filter The patented design uses metallic filter cartridges with a long service life. Thanks to the high degree of separation, clean wood gas is supplied to the engine. Flare line Automatic safety feature and is used to compensate the gas flow of the plant. Gas cooler Hot gas must be cooled before it enters the engine. Since it is connected to the water circuit, this is the first source of heat. Safety filter The safety filter is unique in the industry. Other remaining microparticles arefiltered out of the gas. Ash container and ash box Due to the efficient gasification process, only little ash is produced and the ash is free of toxic substances. No additional costs for waste disposal.

Technology of the 50 kWel plants

Carburator

Wood gas generation

Heat Exchanger

Wood gas cooling

Filter

Wood gas is freed from ash

Ash discharge

Ash is discharged from the system

Engine

Wood gas is burned in the engine

Generator

Power generation

Heat Exchanger

Heat recovery from exhaust gas

Control Cabinet

Technology of the Plants with ≥ 135 kW Units

Fuel Supply

The wood chips are fed into our system via a screw conveyor.

3-part wood carburetor

Our carburetor has tested technology, which guarantees stable operation, low maintenance and long service life.

Double tube

The syngas from the gasification process is fed to our hot gas filter.

Hot gas filter

The patented design uses metallic filter cartridges with a long service life. Thanks to the high degree of separation, clean wood gas is supplied to the engine.

Flare line

Automatic safety feature and is used to compensate the gas flow of the plant.

Ash container and ash box

Due to the efficient gasification process, only little ash is produced and the ash is free of toxic substances. No additional costs for waste disposal.

Gas cooler

Hot gas must be cooled before it enters the engine. Since it is connected to the water circuit, this is the first source of heat.

Safety filter

The safety filter is unique in the industry. Other remaining microparticles are filtered out of the gas.

Biomass cogeneration plant and its function:

Converting waste heat into usable energy.

Biomass cogeneration plant and its function: Converting waste heat into usable energy.

A great deal of heat – known as waste heat – is generated both during the gasification process, in the subsequent gas treatment process, and in the biomass CHP unit. This includes hot exhaust air, hot water from the wood gas and engine cooling, and hot exhaust gases from the CHP unit. While other power plants often let this waste heat go to waste, our biomass CHP units convert it into usable heat thanks to heat exchangers.

If more heat is produced than necessary or if the heat consumption is not always constant, it can be temporarily stored in a buffer tank and used at another time.

Biomass cogeneration plants therefore have a decisive advantage over conventional power plants: they produce electricity and heat in a process called combined heat and power (CHP). If biomass, such as wood, is now used as a fuel instead of natural gas or crude oil, companies can produce electricity and heat in a climate-friendly, cost-saving way and, above all, around the clock.

If cold is also produced from the heat, one even speaks of CHPC (Combined Heat, Power and Cooling) instead of CHP. Biomass cogeneration plants thus usually convert more than 85 percent of the renewable fuels used into usable energy – it hardly gets any more efficient than that.

Good to know: Wood as fuel

To maximize economic efficiency, it’s best to consume the generated electricity and heat on-site. Therefore, wood-fired power generation via a biomass CHP unit is suitable for industry and agriculture with larger electricity and heat requirements or for somewhat larger properties. If the generated electrical energy is not completely consumed, it is possible to feed it into the public networks. For this, biomass CHP operators receive a feed-in tariff – a government-fixed subsidy for self-generated electricity.

Would you like to learn more about our technology? Then we look forward to being able to advise you personally.

This is what a biomass CHP for wood conversion can do.

A biomass cogeneration plant for wood-fired power generation is not only highly efficient in terms of economy and ecology, but also offers a wide range of possible applications.

Here are some examples of possible applications:

  • Wood chip drying
  • Drying or heating purposes in the production process
  • Generation of cooling energy via absorption chillers for cold storage, air conditioning, etc.
  • Conversion of waste heat into electricity (e.g. ORC)

We have summarized the most important applications for you:

Power and heat generation

Biomass CHP units can therefore supply buildings (e.g. hotels, residential complexes, hospitals) with electricity as well as heat their heating systems and drinking water. This makes biomass CHP plants among the most efficient and - when using biomass such as residual wood or waste wood - among the most climate-friendly energy producers.

Process heat generation

Biomass CHP units are by no means only suitable for use in buildings. On the contrary, a biomass CHP unit is particularly interesting for manufacturing companies because it works especially efficiently in generating process heat, usually in the form of hot water - in other words, heat that is needed for industrial and commercial processes. Process heat is usually consumed constantly throughout the year; ideal conditions for biomass CHP units.

Cold generation

If a combined heat and power plant is equipped with an absorption chiller, the heat generated can be converted into cold and used for cooling. This process is called combined heat, power and cooling (CHP). It makes optimum use of the energy generated. CHP plants are especially beneficial in industries with a year-round cooling requirement for air conditioning or process cooling. These include hotels, office buildings and hospitals, but also the food industry. Heat can even be used to produce drinking water from the air via intermediate cooling.

Power and heat generation

Biomass CHP units can therefore supply buildings (e.g. hotels, residential complexes, hospitals) with electricity as well as heat their heating systems and drinking water. This makes biomass CHP plants among the most efficient and - when using biomass such as residual wood or waste wood - among the most climate-friendly energy producers.

Process heat generation

Biomass CHP units are by no means only suitable for use in buildings. On the contrary, a biomass CHP unit is particularly interesting for manufacturing companies because it works especially efficiently in generating process heat, usually in the form of hot water - in other words, heat that is needed for industrial and commercial processes. Process heat is usually consumed constantly throughout the year; ideal conditions for biomass CHP units.

Cold generation

If a combined heat and power plant is equipped with an absorption chiller, the heat generated can be converted into cold and used for cooling. This process is called combined heat, power and cooling (CHP). It makes optimum use of the energy generated. CHP plants are especially beneficial in industries with a year-round cooling requirement for air conditioning or process cooling. These include hotels, office buildings and hospitals, but also the food industry. Heat can even be used to produce drinking water from the air via intermediate cooling.

Good to know

It makes the most economic sense to consume the generated electricity and heat yourself if possible. Therefore, wood-fired power generation via a biomass CHP is suitable for industry and agriculture with larger electricity and heat requirements or for somewhat larger properties. If the generated electrical energy is not completely consumed, it is possible to feed it into the public networks. For this, biomass CHP operators receive a feed-in tariff – a government-fixed subsidy for self-generated electricity.

For whom is a wood-fired power generation worthwhile?

Wood processing industry: sawmills, carpentry, furniture industry, pellet or wood chip plants

The wood processing industry requires a great deal of heat for its smooth operation - for example, for its wood drying kilns. In addition, there are often large quantities of residual wood or waste wood that can be used. Such productions rarely stand still and therefore there is a constant demand for heat. Thus, biomass CHP units with wood-fired power generation are efficient and environmentally conscious solutions for supplying energy - not only with heat, but also with cost-effective electricity.

Leisure: hotels, spas, swimming pools, resorts

Energy costs in the leisure sector often account for five percent or more of total operating revenue, as reported by the Arbeitsgemeinschaft für sparsamen und umweltfreundlichen Energieverbrauch e.V. (Working Group for Economical and Environmentally Friendly Energy Consumption). Biomass-based CHP units are the ideal way to save money: With their help, the overall efficiency can be increased to over 85 percent, representing an improvement of up to 40 percent compared to conventional systems.

Local heating networks: Residential complexes, shopping centers

In larger residential complexes, there is a constant year-round demand for hot water and electricity. Due to this constant demand, a biomass cogeneration plant can therefore also operate economically here, as it is sufficiently utilized.

Agriculture: livestock and poultry farming, greenhouses, nurseries

The use of a combined heat and power unit is particularly useful in agriculture and, for example, air-conditioned animal stables or greenhouses with a constant demand for heat, reports the Deutscher Landwirtschaftsverlag.

Public facilities: Schools, hospitals, homes, prisons

Public facilities must be supplied with electricity and heat around the clock and all year round. These are ideal conditions for a combined heat and power plant to work efficiently and make an important contribution to climate protection by using biomass such as wood. Schools also need to be supplied with energy almost all year round. Here, too, a biomass CHP is the ideal solution.

Wood gas and biomass cogeneration plant: advantages at a glance

Biomass cogeneration plants based on wood gas can score with a whole host of advantages. The biggest bonus is the combination of economic efficiency and climate protection. Biomass cogeneration plants usually convert more than 85 percent of the fuels used into usable energy. If you then also use the cost-effective and at the same time environmentally friendly wood pellets or wood chips as fuel, you save noticeable money.

For whom is a wood-fired power generation worthwhile?

Wood processing industry: sawmills, carpentry, furniture industry, pellet or wood chip plants

Learn more

The wood processing industry requires a great deal of heat for its smooth operation - for example, for its wood drying kilns. In addition, there are often large quantities of residual wood or waste wood that can be used. Such productions rarely stand still and therefore there is a constant demand for heat. Thus, biomass CHP units with wood-fired power generation are efficient and environmentally conscious solutions for supplying energy - not only with heat, but also with cost-effective electricity.

Leisure: hotels, spas, swimming pools, resorts

Learn more

Energy costs in the leisure sector often account for five percent or more of total operating revenue, as reported by the Arbeitsgemeinschaft für sparsamen und umweltfreundlichen Energieverbrauch e.V. (Working Group for Economical and Environmentally Friendly Energy Consumption). Biomass-based CHP units are the ideal way to save money: With their help, the overall efficiency can be increased to over 85 percent, representing an improvement of up to 40 percent compared to conventional systems.

Local heating networks: Residential complexes, shopping centers

Learn more

In larger residential complexes, there is a constant year-round demand for hot water and electricity. Due to this constant demand, a biomass cogeneration plant can therefore also operate economically here, as it is sufficiently utilized.

Agriculture: livestock and poultry farming, greenhouses, nurseries

Learn more

The use of a combined heat and power unit is particularly useful in agriculture and, for example, air-conditioned animal stables or greenhouses with a constant demand for heat, reports the Deutscher Landwirtschaftsverlag.

Public facilities: Schools, hospitals, homes, prisons

Learn more

Public facilities must be supplied with electricity and heat around the clock and all year round. These are ideal conditions for a combined heat and power plant to work efficiently and make an important contribution to climate protection by using biomass such as wood. Schools also need to be supplied with energy almost all year round. Here, too, a biomass CHP is the ideal solution.

High efficiency

The simultaneous production of electricity and heat results in the use of over 85 percent of the fuels.

Weather independence

Unlike wind energy and solar plants, biomass CHP units operate completely independently of weather conditions and the time of day. The biomass CHP units run when there is no wind, rain, snow and frost, and of course also at night.

Long maturities

The plants are designed to operate for 7,000 to 8,000 hours per year. In individual cases, there are plants that even exceed this in practice.

Less CO2 emissions

By using wood as biomass, the carbon cycle is CO₂-neutral. In addition, biomass CHP units primarily use residual and waste wood.

Numerous funding opportunities

Those who decide in favor of a biomass cogeneration plant can count on subsidies and favorable loans from the federal and state governments. This means that the initial costs can usually be easily covered and short payback periods can be achieved.

Value enhancement

A biomass CHP plant can be designed as an integral part of the building and increases the value of the property. Alternatively, biomass CHP units can also be built in containers and can be used flexibly.

Independence

Providers make themselves independent of the expensive electricity of the large energy suppliers. Another bonus in terms of independence: In the event of power outages, a biomass cogeneration plant continues to generate electricity.

Wood gas and biomass cogeneration plant: advantages at a glance

Biomass cogeneration plants based on wood gas can score with a whole host of advantages. The biggest bonus is the combination of economic efficiency and climate protection. Biomass cogeneration plants usually convert more than 85 percent of the fuels used into usable energy. If you then also use the cost-effective and at the same time environmentally friendly wood pellets or wood chips as fuel, you save noticeable money.

The simultaneous production of electricity and heat results in the use of over 85 percent of the fuels.

Unlike wind energy and solar plants, biomass CHP units operate completely independently of weather conditions and the time of day. The biomass CHP units run when there is no wind, rain, snow and frost, and of course also at night.

The plants are designed to operate for 7,000 to 8,000 hours per year. In individual cases, there are plants that even exceed this in practice.

By using wood as biomass, the carbon cycle is CO₂-neutral. In addition, biomass CHP units primarily use residual and waste wood.

Those who decide in favor of a biomass cogeneration plant can count on subsidies and favorable loans from the federal and state governments. This means that the initial costs can usually be easily covered and short payback periods can be achieved.

A biomass CHP plant can be designed as an integral part of the building and increases the value of the property. Alternatively, biomass CHP units can also be built in containers and can be used flexibly.

Are you interested?

Contact us now free of charge and without commitment. With brief information about your needs, the location of your company and what your expectations are, we can advise you on how a biomass CHP system can be used in your company.

Contact us

Which fuels are suitable
for a wood-based biomass cogeneration plant?

The operation of a typical combined heat and power plant is possible with various fuels. Fossil fuels such as natural gas, heating oil or diesel are still the order of the day – but they do not contribute to environmental protection. This is where renewable raw materials come into play, which are ideally suited for biomass CHP units and thus make an enormous contribution to climate protection.

The following biomass fuels can in principle be used for wood-fired power generation in a CHP unit by means of an upstream gasification technology:

Wood pellets

Wood pellets are compressed wood shavings that are mainly made from sawdust. As they have a uniform shape and high quality, they are very suitable for our biomass CHP plants. The pellets are transported to the gasifier via a hose conveyor.

Advantages:

– Space-saving alternative, as the pellets are ready for processing
– High standardization and therefore good gasification
– The clean and tidy alternative
– Less service and maintenance work for the machines

Wood Chips

Wood chips are produced from residual wood, e.g. from forest wood, sawmill by-products or industrial waste wood. Wood chips are particularly suitable as fuel for combined heat and power plants in rural areas, as more space is required to store the material. The wood chips are transported to the gasifier by a screw conveyor, where they are converted into wood gas.

Advantages:

– Inexpensive material
– Easy to use for sawmills or other woodworking industries
– Supplier market is very developed and therefore the deliveries are easier to plan

Wood Briquettes

Wood residues from wood processing, such as planing or sawdust, are compressed into wood briquettes.

Advantages:

– Inexpensive material
– Easy to use for sawmills or other woodworking industries
– Supplier market is very developed and therefore the deliveries are easier to plan

Wood pellets

Learn more

Wood pellets are compressed wood shavings that are mainly made from sawdust. As they have a uniform shape and high quality, they are very suitable for our biomass CHP plants. The pellets are transported to the gasifier via a hose conveyor.

Advantages:

– Space-saving alternative, as the pellets are ready for processing
– High standardization and therefore good gasification
– The clean and tidy alternative
– Less service and maintenance work for the machines

Wood Chips

Learn more

Wood pellets are compressed wood shavings that are mainly made from sawdust. As they have a uniform shape and high quality, they are very suitable for our biomass CHP plants. The pellets are transported to the gasifier via a hose conveyor.

Advantages:

– Space-saving alternative, as the pellets are ready for processing
– High standardization and therefore good gasification
– The clean and tidy alternative
– Less service and maintenance work for the machines

Wood Briquettes

Learn more

Wood residues from wood processing, such as planing or sawdust, are compressed into wood briquettes.

Advantages:

– Inexpensive material
– Easy to use for sawmills or other woodworking industries
– Supplier market is very developed and therefore the deliveries are easier to plan

How much does a biomass CHP unit for wood-fired power generation cost?

A wood-fired power generation plant is an individual solution, where the investment costs and also the running costs can be very different. In addition, the different fuels and, if applicable, their processing also result in different costs. Depending on the application in the process or in the building, however, different subsidy amounts also come into play, so that a generalization of the total costs is hardly possible.

You want to learn more?

Please feel free to ask us for a first rough cost estimate, which you can use for further planning.

Contact us

Environmental friendliness is rewarded: subsidies for wood-fired power generation plants.

Companies that use a biomass cogeneration plant to generate electricity from wood and thus contribute to climate protection receive financial support at many levels in Germany. In addition to the feed-in tariff for surplus electrical energy, the German Federal Ministry of Economics and Export Control (BAFA) promotes corresponding projects, often in the areas of process heat or energy efficiency.

The Kreditanstalt für Wiederaufbau (KfW) also supports climate-friendly rethinking with promotional loans and repayment subsidies of up to 55 percent of the eligible costs. And the individual federal states and regions also reward the use of biomass CHP units as progressive and environmentally friendly energy generation.

Are you interested?

Contact us now free of charge and without commitment. With brief information about your needs, the location of your company and what your expectations are, we can advise you on how a biomass CHP system can be used in your company.

Contact us

Do you have questions?

We have compiled the answers to important questions for you.

Is a biomass CHP unit worthwhile for my company?

A biomass CHP unit with wood-fired power generation is particularly worthwhile for companies that require constant large amounts of thermal energy for their operations – even in summer. This is because a biomass cogeneration plant is only maximally economical if it operates at full load for a certain number of hours per year. Alternatively, excess heat energy can also be converted into cooling energy in the summer.

What are the requirements for the use of a CHP unit?

Our CHP units generate electricity and heat all year round. Therefore, there should be sufficient electricity and heat demand throughout the year.

Technical requirements:
To ensure a smooth start-up of the system on site, the customer will provide the following on-site installations:

  • Foundation with sufficient access to all system components
  • Sufficient building (if installed indoors)
  • Sufficient air supply with adequate circulation rate (if installed in the building)
  • Three-phase connection with 400 V, 100 A
  • External fuel silo in close proximity to the E5 unit.
  • Space for conveyors and storage
  • Space for ash house for ash discharge
  • Heat extraction (5000 l/h ∆T 25°C)

How much does a biomass CHP unit for wood-fired power generation cost?

A plant for wood-fired power generation is a very individual solution, where the investment costs and also the running costs can be very different. In addition, the various fuels and, if applicable, their processing also result in varying costs. Depending on the application in the process or in the building, different subsidy amounts also come into play, so that a generalization of the total costs is hardly possible.

What fund support options are available?

Companies that use wood-fired power generation by means of a biomass cogeneration plant to generate energy and thus make a contribution to climate protection receive financial support at many levels in Germany. In addition to the feed-in tariff for surplus electrical energy, the German Federal Ministry of Economics and Export Control (BAFA) supports corresponding projects.

The Kreditanstalt für Wiederaufbau (KfW) also supports climate-friendly rethinking with development loans and repayment subsidies of up to 55 percent of the eligible costs. And the individual German states and regions also reward the use of biomass CHP units as progressive and environmentally friendly energy generation.