Where does our heat come from and why should I care?

In winter, we do not want to freeze and take a well-tempered shower all year round. We are used to turning a small knob and – poof – it’s warm. But do you know where the heat comes from that keeps your home warm?

The timeline shows that “turning the dial” is a very short period of time compared to the duration of human history.

It is easy to see here that central heating systems currently predominate and that these are preferably operated with gas or fuel oil.

How does the way we heat affect our planet and thus our future?

There was something… the greenhouse effect

The natural greenhouse effect ensures life-friendly conditions on our planet. But the higher the concentration of greenhouse gases in the atmosphere, the more our planet heats up. Since industrialization (in Europe from 1760 /1800), we have been emitting huge amounts of greenhouse gases into the atmosphere – mainly through the combustion of oil, natural gas and coal.

Climate science predicts that the average global temperature will increase by 2.0 to 3.6 degrees Celsius by 2100, despite the climate protection measures currently adopted. Such drastic heating is an existential threat to life on Earth.

Anthropogenic climate change has various causes:
It can also be converted to the individual citizen:

This article is about den Share of climate changewhich is through heating heating In the broader sense, the sectors of energy, industry, buildings and biomass should be mentioned here. In particular, however, the focus will be on the building sector.

Gas as a bridge technology

By now it is clear to everyone that we have to get away from coal, oil and natural gas, otherwise we will destroy our own livelihood on this planet. It is ironic that gas has been classified as sustainable in the “EU Taxonomy for Sustainable Green Economic Activities” set of rules. According to the EU definition of sustainable investment, power plants whose greenhouse gas emissions remain below 100 grams of CO₂ per kilowatt hour are considered sustainable. Some of the gas-fired power plants can meet this benchmark under certain conditions. However, the calculation does not include the considerable methane emissions from upstream processes such as extraction and transport. The consequences could be subsidies for supposedly sustainable (and newly built!) plants that do not support Germany’s climate goals but will continue to operate for two or more decades for economic reasons. Can this be useful bridging technology? A current example shows that our political decision-makers have either not understood the issue of climate emergency or have not thought it through far enough: The municipality of Mauer (where one of our offices near Heidelberg is located) and six other municipalities on the Elsenz River have just signed a concession agreement with Netze BW for gas supply over 20 years. This means that new gas pipelines are still being built in Germany at the present time – right on our doorstep! It is doubtful that these will later be used to transport hydrogen.

Excursus: green hydrogen

Hydrogen is mainly produced from water using the electrolysis process. The term “green hydrogen” is used when the electricity for splitting the water into hydrogen and oxygen comes from renewable sources. In a second step, synthetic methane can also be produced from it.

These two gases are certainly important for the energy transition, for example to decarbonize the steel industry or air traffic. However, an enormous amount of energy is lost in the manufacturing process, which is why a lot of renewable electricity and thus land is needed. This means that hydrogen is not available in unlimited quantities. Using it to heat buildings would be a waste. Fortunately, there are more efficient and less expensive renewable alternatives in the building sector.

Justifying new gas pipelines or even CHP plants on the grounds that they could later run on hydrogen is misleading greenwashing.

Petroleum constant

Oil and gas are fossil fuels and are finite. The fact that reserves are not running out after all is due to the fact that new methods, such as fracking, have been developed to access deeper deposits. What sounds positive at first is a disaster because fracking brings numerous undesirable side effects – see natural gas chart.

District heating

District heating is heat that is not generated in one’s own home, but comes from a power or heating plant in the surrounding area. Usually, water is heated there by combustion, which is then piped to the consumers through insulated (usually underground) pipes. Once in the residential building, hospital or office building, the energy is transferred to the building’s heating circuit in a transfer station, where it provides space heating and hot water.

In over 80 percent of cases, district heating in Germany comes from combined heat and power (CHP) plants. This means that not only heat is generated here, but also electricity at the same time, which saves around 40 percent of primary energy and thus protects the environment. But there is a huge downer:

Especially in densely populated areas, district heating could make a valuable contribution to decarbonization. If you look at the statistics above, however, you can clearly see that Germany is still a long way from this, because virtually only fossil fuels are used. With district heating, you can’t choose your supplier the way you can with electricity. You have to take the one that operates on site.

Heat pump

This graph is only a rough guide. This is because actual emissions are higher for oil and natural gas (due to methane escaping during extraction). A distinction must also be made, for example, between conventionally extracted natural gas from Norway and fracked gas from the USA.

But what does that have to do with you exactly? You’ve probably already guessed: your actions are also crucial! To a certain extent, it is in your hands how your, my, our future and that of future generations on this planet will be shaped.

You can do that as a tenant:

  1. Reduce heat consumption:
    • Use water-saving shower heads and take shorter showers
    • Lower room temperature by 1°C saves 6 % energy
  2. Connect a balcony solar system
  3. The period until the heating system is replaced can be bridged with a biogas tariff for a gas-fired heating system. Since the term “biogas” is not protected, it makes sense to inquire well beforehand. Here is a first aid: https://utopia.de/ratgeber/biogas-anbieter/
  4. Talk to the landlord in a friendly way about different options: see under “What you can do if you own a property”

You can do that if you are the owner of a property:

  1. The state subsidizes modernization and replacement of old heating systems. In any case, inform in advance – e.g. here: https://www.co2online.de/modernisieren-und-bauen/heizung/foerderung-fuer-heizungen/#c144991
  2. https://www.wwf.de/fileadmin/fm-wwf/Publikationen-PDF/Klima/WWF-Ratgeber-f%C3%BCr-klimafreundliche-Heizsysteme.pdf
    • Hydraulic balancing can save 15% energy.
      BAFA subsidizes hydraulic balancing, including pump replacement, with 20 percent of the net costs. The Energy Saving Ordinance also requires hydraulic balancing for residential buildings with at least ten residential units by September 30, 2023, and for residential buildings with six residential units by September 15, 2024.
    • Up to 10% heating costs can be saved with programmable thermostats for the radiator.
    • Insulate heating pipes
  3. With a thermal imaging camera, weak points, such as windows, on the building can be detected and remedied. Good insulation conserves resources and saves costs.
  4. See also: What can you do as a tenant.

You can do that when you build your own house:

  1. Find out in advance which heating technology is best for your building project. Include sustainable thoughts in your reflections: https://www.wwf.de/fileadmin/fm-wwf/Publikationen-PDF/Klima/WWF-Ratgeber-f%C3%BCr-klimafreundliche-Heizsysteme.pdf
  2. Low-energy houses with good insulation and efficient ventilation systems can reduce heating requirements by up to 95%.
  3. See also: What can you do if you are the owner of a property.

Compared to the existence of living organisms on our planet, Homo sapiens has only existed for a very, very short time. In relation to human history, industrialization with the accompanying excessive use of coal, oil and natural gas is also an unimaginably short period of time. And yet, in this small span of time, man has managed to put his own existence at risk through his way of life.

Let’s make the right decisions together!

The good thing is that no one has to freeze for this, because in terms of heating, there are ready-to-use solutions: In particular, heat pumps (powered by green electricity) and green district heating networks in combination with the reduction of heat demand through energy refurbishment are currently the best means to decarbonize the building sector.

Tiled stove on the Veste Oberhaus in Passau – Many thanks for the fantastic trip to Christian, Yousef and especially to Prashanth for the idea

Your Adela


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