European Biogas Electricity Production Hits 17272GWh a Year

Date: 29/09/2008
In the biogas field, Germany has built itself a world-leading position. The country built 820 systems in 2006, increasing the total installed production units to 3700 and is now the No 1 world biogas-based energy producer, and also the technological leader.

CIAT plays a major role in this country, with approximately a 35percent share of the market, and has acquired significant know how in gas treatment, enabling it to propose systems adapted to ever widening scopes of application. This concept has brought about specific developments in this field. Two installations produced with the German partners of CIAT, SEVA AG and SILOXA AG, perfectly illustrate this progress.

European Biogas electricity production in 2006 was 17272GWh per year, of which 7338GWh was by Germany alone. Biogas now represents 1.2percent of the annual production of electricity and nearly 10percent of renewable energy, with an installed power close to 1500MW.

In particular, this success is due to efficient regulations, intended to promote renewable energies.

In fact, the German law stipulates the purchase price per kWh by energy distributing companies for 20 years. This price takes into account the ‘green’ nature of the energy and recompenses the operators, based on efficiency, technological innovation and agricultural re-conversion criteria.

During the first year, in certain cases it may reach 0.18E/kWh. This incentive, combined with the power of German industry, makes Germany the most advanced country worldwide in biogas based energy production systems.

There are several different types of biogas production systems. Biogas production always means production of electricity using a gas engine and an alternator.
Process heat can also be recovered. This is called cogeneration. Biogas is a gas produced by the fermentation of animal or vegetable organic matter without oxygen.
Fermentation is also called methanisation and occurs naturally (in swamps) or spontaneously in waste dumps containing organic waste.

Also, it can be artificially produced in digesters (when treating purification sludge, industrial organic waste or selected agricultural crops, etc).

Biogas can also be recovered by sucking mine gas. In all cases, the biogas must be dehumidified and purified before combustion; otherwise it can damage the gas engine.

Biogas is a mixture essentially comprising methane (30 to 70percent) and carbon dioxide, with varying quantities of water and hydrogen sulphide (H2S).

Other compounds can also be found from contamination, especially in waste dump biogas: ammonia, hydrogen, nitrogen and carbon monoxide.

Biogas energy is only produced from methane and is in fact a renewable form of fossil energy, which is natural gas. Furthermore, biogas systems are highly respectful of the environment. In fact, the contribution of a methane molecule (CH4) to the greenhouse effect is 21 times greater than that of a carbon dioxide molecule. Therefore burning methane, even though producing CO2, reduces its impact on the environment.
SEVA has developed forefront know-how for small-sized systems. Out of the 820 installed in Germany in 2006, this company, with a payroll of 150, produced 170 biogas combustion units, with a total cumulative 54 MW power.

The philosophy at SEVA ENERGIE is to make biogas profitable by offering high production rate systems, operating continuously with limited human intervention and very high reliability.

CIAT has become a recognised standard for the up-line treatment part of gas. As previously mentioned, the humidity is removed from the gas. Steam is condensed by cooling the gas to temperatures between 15 and 5°C. The advantage of this process is to eliminate part of the impurities in gas by trapping them in the condensates,which are evacuated.