In the USA, it was investigated how much gas escapes from a gas cooker when it is not burning and how harmful the emissions are for the climate. In small kitchens, the recommended limits can be exceeded within a few minutes.
In more than one third of American households, that is more than 40 million, a gas cooker is used for cooking. Studies in the USA have now revealed how much gas escapes from ovens and cookers. When switched off, more than three quarters of the methane emissions escaped. But not only methane, but also nitrogen oxides were produced. This is usually due to the fact that the pipes are often dilapidated and the fittings are not up to date.
Of course, the conditions cannot be transferred one-to-one to Europe. There are far fewer gas cookers in this country. In Germany, only about 7 per cent of cookers are operated with gas. Also, in a country with an intact infrastructure, which includes Germany, less gas is likely to escape than from dilapidated pipelines. In Germany, methane is produced primarily in agriculture and then especially in factory farming. A lot of methane is also released in sewage treatment plants and landfills.
Methane is 25 times more potent than carbon dioxide and thus much more harmful to humans and the environment. Calculated over 20 years, methane is 86 times more harmful than CO2 and is responsible for about 25 per cent of global warming. If methane emissions were reduced by 45 per cent, the average temperature could be reduced by 0.3 degrees Celsius by 2030. All the gas furnaces in the US together have the effect on the climate in one year as about 500,000 cars.
The research makes it clear that it will not only take the introduction of driving bans and environmental zones in cities to reduce harmful air pollution, but also the modernisation of existing structures.