Chapter 1  Overview of Biogas Extension An overview of biogas extension work considers the background to the development and use of the technology in less developed countries. The technology is placed in the wider global context of a concern for the environment since the early 1970s. It offers a long list of benefits to the users of the technology. A brief history looks at its origin in India and China, as well as applications for sewage processing in Europe and USA. The benefits of biogas technology for small farmers led to programmes in China and India, which inspired the programme in Nepal. This book is the latest publication following a series of reports and a previous book about the biogas programme in Nepal. People in Europe and USA have only lately realised that a technology for processing sewage is also a good source of renewable energy.  (75 references). http://dx.doi.org/10.3362/9781780448497.001 Chapter 2  Biogas History in Developing Countries Three large biogas programmes in the developing world: in China, India and Nepal, have been growing since the 1970s. Some of the smaller biogas programmes in other countries also started in the 1970s, but did not grow at the same rate. The history of the three large programmes offers insights into the reasons for their success. Other programmes in countries in the rest of Asia, in Africa and in Latin America are considered, so comparisons can be made. Biogas programmes in many of these countries are now being influenced by lessons learned from the larger programmes.  (90 references). http://dx.doi.org/10.3362/9781780448497.002 Chapter 3  Aspects of a Biogas Programme The process of making biogas technology available widely in a country involves a large number of different factors. The provision of domestic biogas units to very large numbers of people, as done in China, India, Nepal and elsewhere requires very careful planning and there are many challenges that face people who work on such a project. There are many benefits of biogas technology, such as replacing firewood or LPG.  Biogas plants can be made at a range of different scales, from small backyard systems to large industrial systems. Particular challenges are faced in the economic, organisational and research and development areas.  (45 references). http://dx.doi.org/10.3362/9781780448497.003 Note: clicking on a dx.doi link gives a list of references in that chapter, as well the oportunity to download the text as a PDF file, for a fee.