Compressed natural gas or CNG has become an affordable and eco-friendly alternative to petrol and diesel fuel with an increasing share on the fuel market.

Natural gas is a gaseous fossil fuel whose calorific value and other characteristics are equivalent to the biomethane that is produced from renewable sources.

Biomethane has been produced in Estonia since 2018. Biometaan OÜ in Koksvere, Viljandi County produces gas from manure and biomass, the production plant of Rohegaas OÜ in Kunda, however, uses sewage sludge to produce domestic green gas. In the summer of 2020, two new production plants – Vinni Biogaas OÜ and Tartu Biogaas OÜ – were founded, both producing biomethane from animal manure, bio-waste and food industry waste. There will be more manufacturers soon.

Biomethane saves nature and money

In addition to being friendly to the environment and our wallets, biomethane production also contributes to the functioning of the circular economy. So far, biowaste tends to be a problem – the Republic of Estonia is threatened by a fine from the EU Commission for failure to meet the waste recycling goal deadline. Producing biomethane from bio-waste offers a solution that is both eco-friendly and cheap for the consumer.

Biomethane is produced from local waste and biomass. The source material can be manure, silage, mowed green grass, vegetable foliage, biodegradable waste, waste from restaurants, cleaning waste from dairy, bread and grain storage facilities or waste from the meat processing industry – anything organic except for wood. Some of the source materials required for the production of biomethane require heat processing so that the fermentation residue can be used as fertiliser, but biomethane production does not generate any waste. This is also an example of the circular economy: waste is taken into use and products are produced with no waste.

In simple terms, biogas production imitates a cow’s stomach. The heat in an oxygen-free production tank is 37-40 degrees. In the course of the process, the bacteria decompose and transform biomass into biogas, which becomes biomethane with a methane content of 96-98% after purification from carbon dioxide.

Increasingly diverse petrol station network

Biomethane can be used everywhere that currently uses natural gas, including cars that use compressed gas (CNG). Today there are 23 CNG fuelling stations in Estonia and their number is increasing.

Eesti Gaas was the first to start offering biomethane at Estonian fuelling stations in April 2018. In recent years, the domestic fuel market has seen strong development – in addition to the network of Eesti Gaas AS, Alexela as has also created a CNG fuelling network, and there are other newcomers such as JetGas OÜ, Krooning AS and Olerex AS. It is also possible to refuel at the production plant of Biometaan OÜ.

The price of fuel is also affordable: driving a passenger car that uses CNG costs around 3.5 euros for 100 km, while the average cost of a petrol-based vehicle is 7 euros per 100 km – the exact cost depends on the specific vehicle. Compared to other fuels, the better price per kilometre has made CNG vehicles more popular among private persons as well as in the transport sector in general.

Reducing air pollution together!

When driving with methane fuel, the exhaust gases contain no fine particulate matter, which is often one of the causes of respiratory diseases in cities. Furthermore, the exhaust gases contain almost no sulphur or nitrogen compounds, which cause air pollution and acid rain.

The state has started developing the Estonian biomethane market through various activities. At the moment, the Environmental Investment Centre has supported the construction of 15 fuelling stations with biomethane capacity. In order to prove the origin of the consumed gas, Elering AS as the owner of the main gas network and system operator has created a system of guarantee of origin.