
It is difficult to speak entirely for Europe, but there are member countries of the European Union, which critically depend on the supply of Russian gas, from Finland in the north and ending with the Balkan countries-Bulgaria, Hungary, Slovakia. Without Russian gas, they will very much lack energy. Finland is almost 100%, Bulgaria is 96%, well, in Hungary about 40-50%. It is not yet clear where such a shortage can be replenished, so the ability to do without Russian gas at the European Union is very limited.
If the gas supply suddenly stops, then any of these options will take some time. The first is alternative and renewable sources, like the sun, wind and so on; The second is an atomic energy that to bring to the desired level and abandon the liquidation programs of nuclear power plants, but this will also take a considerable time; The third is energy conservation and increase in energy efficiency; The fourth is an increase in the EU purchases of liquefied natural gas, which will be associated with significant expenses, because this gas will have to be lured with a high price from Asian consumers; The fifth-it is necessary to build some interconnectors across the borders of the EU member countries in order to transfer gas volumes from Western Europe to central and eastern, that is, from those areas where it is easy to survive without Russia. Here is such a program for the construction of interconnectors, but it is far from completed. To make it necessary for some time, and for more than one year.