Biogas is the future CO2-neutral fuel for Danish trucks. The gas is extracted from natural resources such as agricultural manure and household organic waste. The climate wins because methane gas does not dissolve in the air, avoiding its greenhouse effect: it is collected at the facilities themselves and purified to be able to reuse it in vehicles powered by compressed natural gas. When we replace diesel, a fossil fuel, we achieve double climate savings. These advantages are also recognized by the EU, which is why biogas is approved as one of the few advanced biofuels when extracted from manure and organic waste, among other sources.
The gas used as fuel for vehicles consists mainly of methane (CH4). Methane is the simplest hydrocarbon - one carbon atom for every four hydrogen - and therefore emits less CO2 than other hydrocarbons (such as gasoline and diesel). The methane that comes from the subsoil is called natural gas, and the one produced by biological processes (manure, food waste, etc.), biogas. Biogas emits practically no CO2 and is considered a renewable energy source.
In order to use biogas for transport, it needs to be purified (upgraded) from CO2. In this way, the biogas acquires the same quality as natural gas and can be distributed in the natural gas network.
In Denmark, CNG can be obtained directly from the natural gas network and is currently used mainly in city buses and refuse collection vehicles. CNG has the advantage that it can be "refuelled" directly from the gas network, which, however, is also its main limitation, since CNG can only be used in the vicinity of the network.
In Denmark, natural gas for automobiles at service stations is BioCNG, that is, it comes from organic waste, and there is no supply of CNG, of fossil origin, at gas stations open to the public. The price of BioCNG in Denmark is stable and cheap, assuming a viable alternative to traditional mobility