Gas as a fossil fuel for heating briefly presented
Topics at a glance
Alongside oil, gas is one of the most important primary energy sources in Germany. It is not only industry that needs a lot of gas. This fossil fuel is also indispensable for heating residential buildings and apartments. Official statistics show how important gas is in the heating sector, and confirm that gas systems are among the most frequently used heating systems. Around two thirds of all heat generators use gas.
Gas as a drive energy and source fuel for heating systems
The best-known kind of heating system runs on gas. It burns the fuel, generating heat in the process. It is able to burn the fuel not only in gaseous form, but also in liquid form (liquid gas). But it is by no means the only type of heating that uses gas as an energy supplier. Combined heat and power units, for example, burn gas to drive a turbine, which in turn generates electricity and heat. Heat pumps also use either electricity or gas as drive energy to power a compressor. One special type of heating system is fuel cell heating. It too uses gas as an energy source to generate heat and electricity. But here's the trick: it doesn't burn the gas, but separates it chemically. The actual fuel in this case is not the gas itself, but the hydrogen reformed from it.
Formation & reserves
Gas, in this case natural gas, forms in a very similar way to crude oil. Both raw materials were formed several million years ago from organic substances and lie in deposits, some of which are huge. Natural gas itself is a mixture of methane, nitrogen and other hydrocarbons such as ethane, propane and butane. Among other things, it can be extracted from the depths using boreholes. Just a few years ago, natural gas was mostly flared off as a by-product of oil extraction. This is not only a waste of resources, but also pollutes the environment in the long run. Governments in the producing countries have since passed laws banning flaring.
Since the primordial oceans covered a large part of our planet millions of years ago, natural gas is found in almost all regions of the world. The Middle East has the largest reserves, followed by Europe and Eurasia. The list of countries with the largest production volume, however, is not headed by Saudi Arabia, for example, but by the United States of America. Germany also has natural gas reserves of around 123 billion cubic metres. Extraction here is focused on Saxony-Anhalt. But gas can also be produced renewably. The familiar biogas is produced from biomass such as maize, sugar beet or other energy crops in specially built plants.
Reserves and resources
When it comes to the question of whether gas supplies are guaranteed in the coming years, a distinction must first be made between reserves and resources. Reserves refer to the quantities already discovered, while resources refer only to deposits that are not yet economically exploitable. A report by the British oil company BP stated that it will take 55.1 years for natural gas reserves to be completely depleted.
This is assuming that consumption remains constant. The company has taken the figures from 2014 as the basis for this calculation. In that year, almost 4000 billion cubic metres of gas were consumed worldwide. Compared to the reserves already available, the amount of resources that it is not yet scientifically possible to extract is considerably high. The German Association for Natural Gas, Petroleum and Geo-Energy (BVEG) assumes that there is enough natural gas for up to 260 years.
Benefits of using gas
The use of gas has many advantages for both the user and the environment. Due to its high energy content, system owners benefit from extremely economical heating – all the more so if the boiler uses condensing technology. You can read about what makes this technology so special in the section on Benefits of gas condensing technology. One thing is certain: compared to other fossil fuels, gas burns very cleanly. It emits less CO₂ than crude oil, for example, and produces hardly any pollutants such as nitrogen oxides or sulphur dioxide. This means less burden on the environment.
Industry also relies on this fuel. In particular, gas plays an important role in power generation. Compared to conventional power plants, natural gas power stations ramp their operations up and down as required. They are therefore often used to balance peak loads quickly and reliably. Another advantage is the very well established distribution network.
Gas conversion and gross calorific value
The changeover from L-gas to H-gas is currently taking place in north-west Germany. The costs for this are borne by the gas supply utility and the Bundesnetzagentur (German Federal Network Agency). Owners of a gas heating system only need to take note of all the letters, notices and deadlines they receive from their energy supplier. The purpose of this conversion is to guarantee supply and to standardise the type of gas. This is because the gross calorific value, i.e. the energy content, of gas is not always constant. For L-gas, for example, it is between eight and ten kilowatt hours per cubic metre. With H-gas, it's ten to twelve kilowatt hours per cubic metre. If you want to find out the gross calorific value of the gas you're buying, take a look at your gas bill. It is usually stated there. If not, it is worth asking your gas supplier.
If you already own a Viessmann condensing boiler with the intelligent Lambda Pro Control, you will not be affected by the changeover. This is because the combustion controller adapts automatically to the gas quality and can burn energy-rich H-gas without any problems. You can find detailed information on this on the gas conversion page.
