BR-navigation Bayern 1-Expert tips heating with wood How environmentally friendly are pellets?

Wood pellet heaters are particularly popular in Bavaria: According to industry associations, 43 percent of the models sold in Germany are in Bavaria.The increased demand leads to a strong expansion of the production capacities at the manufacturers of Pellets.In the meantime, they not only use waste from the Säge industry, but are also increasingly falling back on forest chopping schnitzel.

Ecologically sensible?

The sudden increased demand for wood pellet heating is therefore in question of their ecological sense.

What are wood pellets?

Wood pellets are a climate -neutral fuel that is obtained from biomass.Ideally, the pellets made from pressed saw and planing chips contain no chemical binders and have a high energy density.Two kilograms of wood pellets correspond to the efficiency of one liter of heating oil.Pellets therefore enable good combustion with high efficiency and low emissions.For example, wood pellet stoves and wood pellet heating boilers have significantly lower carbon monoxide and dust values than other systems for solid fuels.

Basically, wood - compared to fossil energies such as oil and gas - is a renewable raw material.That means: If trees are felled, new trees can be planted.However, it takes time for them to be big enough.Actually, no trees are felled for pellets alone.Wood pellets are the residual fabric in the production of beams or furniture.But since the pellet industry is booming, that could change.

With the waste works of the sawmills, over 200 is already heating.000 households in Germany, in the next few years it should be twice as many.Around three million tons of pellets are currently being produced in Germany, but only about two million are used up.However, the wood for the pellets can still come from so -called "short -conversion plantations" (with fast -growing trees) or wood with a diameter of more than seven centimeters from more than seven -forested surfaces are continuously used.If thinner branches stay in the forest and secure its biological diversity and the natural nutrient cycle, there is - from an ecological point of view - there is nothing to be obtained.

"Compared to other heating systems, pellet systems are characterized by a very low CO2 emissions," says the German Pellinstitut in Berlin.Pellets are also environmentally and climate-friendly in their energy balance: Energy must be used for the procurement of raw materials, for manufacturing and for the transport of pellets.However, this effort is only 2.7 percent (for comparison: the energy expenditure for oil is twelve percent, which is ten percent for natural gas)).

However, the forester and pellet critic Peter Wohlleben points out: "related to the individual tree, this is true.But forests overall are CO2 sinks.Dead trees do not completely rot, but enrich the soil with carbon for centuries.This is how our fossil fuels were created.If the trees are burned, this memory effect is eliminated."

Disadvantage of fine dust

The only real disadvantage of pellet heating: the fine dust pollution.However, the legal provisions have already been tightened and the technical equipment of the heaters has also gotten better.And finally, as Bernhard Zimmer from the Institute for Sustainable Development in Piding says, the pellet heaters are wrongly criticized because they are regulated heating and the fine dust loads that are attributed to the burning of the Holzen.But it is the case that pellet heating emits more fine dust than, for example, oil heating.

However, the decisive advantage from an economic point of view is that wood pellets are much more cost -effective than oil or gas.As a local raw material, no additional tax is charged on wood, such as an eco -tax.Even the VAT is seven instead of 19 percent.The cost of one kilowatt hour of heat is about six cents for gas or.At about nine cent for oil and for a kilowatt hour of pellet or wood chips between three and 4.5 cents.

Wood alternative: wood chips

Wood chips are now increasingly technically dried in stores.However, there are also natural -dried wood chips.These are chopped pieces made of dried, natural wood.Wood chips usually have a flat, rectangular shape.The main area of application for wood chips are the combustion systems of the performance classes between 100 and 1.000 kilowatt hours (KW).

Hackschnitzel are significantly cheaper than wood pellets.A ton of wood chips (forest fresh) costs around 55 to 60 euros, whereby the prices are regionally different.A ton of pellets, on the other hand, costs between 150 and 180 euros.The wood chips usually come from the private small forest in Bavaria.Here the forest wood is often chopped on site and then delivered to the nearby heating power plant.In contrast to pellets, wood chips have a significantly higher space requirement in storage.Ca match in a cubic meter of room volume.650 kilograms of pellets or 180 to 240 kilograms of wood chips.This often leads to a deterioration in the energy balance in wood chips.Another disadvantage: improper storage can form mold, which can lead to high losses.By the way, the heating value (HU) of Pellets is larger than that of wood chips.It is 4.9 kWh/kg and wood/wood chips 3 to 4.5 kWh/kg (depending on the moisture content).

The pellets have their strength in the small central heaters, i.e. in the single -family house or in the apartment building up to 500 kW.In the case of larger systems, the wood chips do better due to conveyor technology and combustion technology.Small wood chip heaters have the disadvantage that they are more difficult to regulate.The various systems also need different qualities of the wood chips, for example, which affects the water content.

Certificates for pellets and wood chips

The extraction of pellets is only environmentally friendly if the wood that is needed every year for pellet production also grows every year.This means that if five tons of wood are cut down, five tons of wood must also be reforested in the forest.It is important that the number of trees does not have to be reforested, but the mass (tons).

Until a few years ago, the tree tops were rotted in the forest and the minerals and nutrients were returned to the soil.In the meantime, the trees are used completely for the production of the pellets, from the root to the treetop.However, one has to weigh up, Bernhard Zimmer, wooden expert from the Institute for Sustainable Development: "If the bark beetle nests in the crowns of the spruces that lie after storms in the forest, it makes absolutely useful to use the wood.So you have to decide from location to location, but of course it should be paid to the nutrient balance sheet."

For three years there has been a valid standard for the quality of wood pellets for three years.However, criteria are only a certain minimum heating value as well as certain requirements for size and diameter of the pellets.So it's just about the quality of the pellets.The certificates Enplus and Dinplus do not necessarily say something about whether the pellets from the region or.come from local forests.After all, the manufacturing routes are understandable.The German pellet institute (Depi), for example, awards the Enplus certificate and thus concludes a usage contract with the customers: "The pellet producer is checked once a year and the course of the production process and removed samples," says the Depi.

Environmental seal "Blue Angel"

The "Blue Angel" has also identified technically dried wood chips and wood pellets since 2010.The heat for drying must be provided either by renewable energies or from industrial waste heat and used efficiently.The fine dust emissions that arise during production must be "strict limit values", is one of the requirement of the "blue angel".It is also stipulated that only wood from sustainable forestry and chemically untreated wooden residues are used for the production of wood chips and wood pellets.Pellets, which are marked with the "blue angel", also depict the transport applications for the delivery of the wooden raw materials and receive the inscription "because sustainable and energy -efficiently produces".

Regine Vogt, from the Heidelberg IFEU Institute, which, together with the eco-institute in Freiburg, has developed exactly such criteria, would therefore also recommend the "blue angel" as a certificate to the consumer, "because it looks at several aspects, as onceGreenhouse gases that there is little emission.But then also the sustainable origin of wood, which is not yet possible with the DIN EN labels.They also think about it, but wood origin is not yet an issue.But it is an important topic, I think."

Finite biomass

Wood should not only be used to burn.

Ecological handling of wood is that its combustion is only at the end of a long recycling chain.The experts then call this "cascade use".It has little to do with a responsible resource policy, to fire wood, to replace fossil fuels, to promote this taxally and ultimately determine that the local biomass cannot be lifted.Because then sooner or later more tropical rainforest will be cut down illegally because the demand is there and it is worth it because of the price.That's why Bernhard Zimmer warns: "There is a border somewhere.When we start to get a renewable decentralized energy source from far to process it centrally.You have to think about it ecologically about it.We have a limited forest area and thus a limited potential for the change."

Costs for pellets rise

Even if the prices for wood pellets and wood chips have increased massively in recent years, they still remain a cheaper alternative to fossil fuels.According to the current price list of the non -profit association C.A.R.M.E.N., the centrale-agricultural raw material marketing and energy network E.V., is the price for five tons of wood pellets (with a delivery within a radius of 50 kilometers) for September 2013 at an average of 270 euros.This corresponds to a price increase of around 50 percent for the period of the past five years.However, since heating oil and natural gas now also cost a lot more, the price for the megawatt hour of energy for wood pellets is still far below that of the fossil fuels.

background

The price development has consequences for industrial energy generation.At the end of October 2013, the Essen energy group RWE closes its biomass power plant in the British Tilbury, which with 750 megawatt worldwide largest power plant of this kind.Investments would have been necessary for the continued operation that would not have expected the difficult market situation, says a RWE spokesman.The prices in electricity wholesale and thus the proceeds of the corporations have also been significantly fell into the UK.The former coal-fired power plant was only switched to biomass pellets in 2010.RWE is apparently dissatisfied with the biomass business.The sale of smaller systems in the Czech Republic, Germany and Italy is at disposition and all options are also examined for the Pellet plant in the USA, as a RWE spokeswoman has confirmed.According to the company, the work produces at least 750 annually.000 tons of wood pellets for export to Europe.

Interesting for private consumers: The Federal Office for Economic Affairs and Export Control (BAFA) continues to subsidize the purchase of pellet stoves with a water pocket.Anyone who is now investing in the purchase of such a device will receive 1.400 euro state support.Anyone who couples the water-bearing pellet oven with a solar system will even receive 3 in total.400 euros as direct help from the state.

Conclusion

Basically, every house must be checked which is the most ecologically sensible heating.Pellets are a good contribution to detach from the dependence on fossil fuels.Heating with the pellets is also largely climate -neutral.However, it is important to pay attention to a meaningful certificate such as the "blue angel" when buying pellet.This is the only way to ensure that a pellet comes from Germany and thus from sustainable forestry.If pellets or wood chips are transported to the scene over long distances, the corresponding greenhouse gas emissions must be included in the overall balance sheet.The "Blue Angel" makes this transparent by having to show the product information from the manufacturer.Consumers can thus have a direct impact on the origin of the biomass and also make a specific contribution to environmental protection.