District heating

Nearly half of the coal heat supply in Europe is burned in household coal stoves, which are almost exclusively located in Poland. Not only do they cause significant CO2 emissions, but the largely unfiltered exhaust gasses also lead to serious air pollution, which causes severe health problems and premature deaths. 

The second half of coal-derived heat is generated in combined heat and power plants (CHP) and, to a smaller extent, in heat-only boilers. These facilities supply mostly urban district heating grids and are primarily located in Poland, Germany, and the Czech Republic. More installations can be found in Northern Europe (Denmark, Finland), Eastern Europe (Slovakia) and South East Europe (Bosnia and Herzegovina, Bulgaria, Greece, Romania). In the Western Balkan countries (in particular Montenegro), there are projects to connect existing conventional coal power plants to district heating systems.

When considering cleaner alternatives to transform the heating sectors, decision-makers mostly opt for gas, or biomass, and for Combined Heat and Power (CHP) technology. None of these are truly sustainable heating solutions. 

Many district heating systems were built around the 80s. They are mostly 2nd generation systems running on high temperatures above 100 C. In some locations like the Western Balkan region district heating is used for space heating only. The old heating networks suffer from poor insulation of pipelines and high losses of heat and water leakage. On the demand side, deep renovations of the existing building stock are lacking, and people often have little or no control over the heat consumption in their homes.

Biomass

Biomass is not a carbon-free fuel: its burning releases greenhouse gases. The theory put forth for why biomass can be considered carbon-neutral is that because trees or other crops used for biomass are replaced, they lock in the carbon that has been released by burning and so the cycle is carbon-neutral. However, addressing climate change is becoming so urgent that we simply cannot afford to wait decades for trees to re-grow, and there are increasing calls for the EU to stop treating biomass as carbon-neutral and to make sure its emissions costs are included in the EU emissions trading scheme. In addition, it cannot really be considered renewable unless strict sustainability standards are in place and are enforced, as it may lead to deforestation or the replacement of old-growth forests with plantations. Another problem is that the concept of biomass is rather vague and can mean different things, so defining what type of biomass could be suitable for large-scale use in district heating systems is important. Sustainability is especially problematic with ‘forest biomass’ and less so when the biomass used as an energy source is made up of wood residue and waste (e.g. residue from furniture production, sawmill facilities, etc.). Yet, more than a third of woody biomass used for energetic use originates from primary wood.

Solid waste

The incineration of waste for heating/CHP is problematic for several reasons. Municipal waste is composed of different fractions, most of which can and should be either prevented, recycled or composted. This is the goal of the EU’s circular economy policy, which includes a commitment to prevent or recycle 65 per cent of municipal waste by 2035. Using waste as a fuel crowds out investments in waste selection and recycling measures.

In addition, burning waste creates air pollution including carcinogenic substances like dioxins and furans. The composition of waste can be highly variable and in some countries there are no strict standards in place to monitor and control what type of waste is used as energy fuel. It is clear from the experience with existing industrial and energy facilities in the Western Balkan region that the authorities are not effective with enforcing pollution control legislation, so it is highly risky to build incinerators. Even where proper filters are used, the ash from the incinerator (about 30 per cent of the weight of the original waste) as well as the highly toxic filter residues, have to be disposed of somewhere, and the Western Balkan countries do not have secure enough facilities for this. In other words, whatever toxic substances are in the waste or are generated during combustion have to end up somewhere – either in the air, ash, or filter residues.