| 1770 | The Italian Volta collected marsh gas and investigated its burning behavior. |
| 1821 | Avogadro identified methane (CH4 ). |
| 1875 | Propoff states that biogas is produced under anaerobic conditions. |
| 1884 | Pasteur researched on biogas from animal residues. He proposed the utilization of horse litter to produce biogas for street-lighting. |
| 1906 | First anaerobic wastewater-treatment plant in Germany. |
| 1913 | First anaerobic digester with heating facility. |
| 1920 | First German sewage plant to feed the collected biogas into the public gas supply system. |
| 1940 | Addition of organic residues (fat) to increase sewage gas production. |
| 1947 | Research demonstrates that the dung of one cow can give a hundred times more gas than the feces of one urban inhabitant. |
| Establishment of the first working group on biogas in Germany. | |
| 1950 | Installation of the first larger agricultural biogas plant. |
| 1950s | Nearly 50 biogas plants are built, fed by litter mixed with water and dung. Low oil prices and technical problems lead to the shutdown of all but two plants. |
| 1974 | After the first 'energy crisis', increased promotion of research on and implementation of agricultural biogas technology by the EC and federal departments. |
| 1985 | 75 biogas plants are listed (built or planned). Biogas slurry is increasingly used as liquid manure. |
| 1990 | Progress due to guaranteed prices for biogas-generated electricity. Progress in optimizing the mixture of substrates, the use of biogas for different purposes and technology details. |
| 1992 | Foundation of the German biogas association 'Fachverband Biogas' |
| 1997 | More than 400 agricultural biogas plants exist in Germany. |
The history of biogas exploration and utilization in China covers a period of more than 50 years. First biogas plants were build in the 1940s by prosperous families. Since the 1970s biogas research and technology were developed at a high speed and biogas technology was promoted vigorously by the Chinese government. In rural areas, more than 5 million small biogas digesters have been constructed and,currently, over 20 million persons use biogas currently as a fuel.
In India, the development of simple biogas plants for rural households started in the 1950s. A massive increase in the number of biogas plants took place in the 1970s through strong government backing. Meanwhile, more than one million biogas plants exist in India.
The historical experiences in Germany, China and India demonstrate clearly, how biogas development responds to favorable frame conditions. In Germany, biogas dissemination gained momentum through the need for alternative energy sources in a war-torn economy and during an energy crisis or later by the change of electricity pricing. In India and China it was a strong government program that furthered the mass dissemination of biogas technology.
In the late 1970's, triggered by Schuhmacher's 'Small is Beautiful', appropriate, simple technologies entered the arena of development work in the South. Not Northern high-tech, but innovative, affordable, simple and traditional technologies, it was believed, were the remedy for the development- and technology-gap between industrialized and developing countries. Following its launching in 1980, GTZ-GATE chose biogas technology as a focal point of its activities. This resulted in a cross-sectoral scheme that has been accompanying and supporting the development and dissemination of biogas technology in Latin America, Asia and Africa.
Industrialized countries neither had sufficient experience nor appropriate technologies to build on in developing countries. Rather, this experience was identified in India and China and transmitted by a South-North-South transfer. The term 'appropriate technology' seemed justified by the fact that this technology was adapted to the respective local conditions during a 'learning-with-developing-countries' process.
A number of biogas dissemination programs involving German Technical Cooperation (GTZ) were launched in Bolivia, Colombia, Nicaragua, the Caribbean (see Belize and Jamaica), Tanzania, Kenya, Burundi, Morocco and Thailand. Initially, biogas and anaerobic technology focused on small scale farmers. At a later stage, larger farms as well as waste treatment issues increasingly became the focus of biogas technology.
These activities have resulted in a number of positive spin-off effects in the partner countries, in Germany, Europe and international development cooperation. Like in other fields of appropriate technology (AT) promotion, environmental protection, energy provision and the support to private enterprise development are increasingly seen as inseparable elements of sustainable (technology) development.
Today, the highest degree of market maturity can be found in the area of municipal sludge treatment, industrial wastewater purification and treatment of agricultural wastes. The use of the technology in municipal wastewater treatment is currently experiencing an upswing in Asia (India in particular) and Latin America. Anaerobic treatment of municipal organic waste is experiencing a boom in Northern Europe. Agricultural biogas plants in developing countries are usually promoted on a large scale in connection with energy and environmental issues, and are installed particularly where water pollution through liquid manure from agriculture is most severe.
The increasing emission of greenhouse gases, increasing water consumption and water pollution, declining soil fertility, unsatisfactory waste management and the growing rate of deforestation must be seen as parts of the unsustainable resource use systems that prevail worldwide. Biogas technology is one of the important hardware components in a chain of measures to counteract the above problems. GATE/ISAT is committed to play a lead role in networking and information exchange to ensure that the potential of biogas technology is recognized and made optimal use of.