Page last updated 30/08/2018
The projects set up in China, India and Nepal continued
effectively in different ways and are described in the “Small-
scale Rural Biogas Programmes”. There is a useful video on
You-Tube, supplied by Ashden.
The technical weaknesses of the early Chinese project were
overcome by the Biogas Research Centre in Chengdu. Quality
standards were published. Technicians were trained to
supervise the building of good quality plants. Many local
agencies were still involved in the building of plants, but they
had to use trained people. The programme did develop at a
slower rate, but with a much lower failure rate. The rate has
since increased again.
The Indian programme became much less centralised, as
groups adapted the fixed dome design for India. KVIC adapted
by developing fibre reinforced plastic floating drums as an
alternative to steel drums. Several designs of fixed dome plant,
were developed, such as the Janata design (with a dome made
from concrete) and Deenabandu design (with a dome made
from bricks). As different NGOs and private companies
manufactured these designs, quality became more variable.
In Nepal, the Gobar Gas company, that had been set up to
make biogas plants, was replaced by many smaller installation
companies (between 40 and 50). However, quality control was
maintained by BSP (Biogas Suport Programme set up
under SNV). The plants that were built mainly used a standard
fixed dome design based from the one developed by DCS
(called the GGC 2047). BSP did careful follow-up work and
found evidence that, for a time, 98% of plants were still
working 5 years after they were built. As the programme has
further developed this figure has unfortunately reduced.
The three programmes were successful, because the respective
governments offered subsidies. This allowed the government
to have central control of quality. The biogas training institute
claims over 12 million plants in China, based on their records,
although the total number of plants in China is now more than
40 million. The numbers in India are less clear, but records
suggest more than 4 million plants. BSP (now Biogas Sector
Partnership) in Nepal had detailed records for over 250,000
plants at the end of 2012 (with a claim of having more per
head of population than anywhere else in the world).
Biogas technology in Europe and the rest of the developed
world went in a very different direction, based on sewage plant
technology. Biogas plant designs were based on steel tanks,
mounted on above ground foundations and had much larger
volumes. A typical farm-scale digester in the developed world
has a volume of 1000 m
3
. They are also seen as a way to
process food wastes and food processing residues to energy
and compost, as an alternative to putting them in land-fill.
The German government set up an incentive scheme based on
a Feed-in-Tariff (FiT) for electricity generated from anaerobic
digestion. This encouraged the use of energy crops, which
were grown specifically to feed to AD plants, such as fodder
maize. Much larger plants (with volumes up to 100,000 m
3
)
were built, although the expected economies of scale were not
realised. Experience and rule changes have led to a slow down
in the programme and a greater number of smaller scale plants
been built. Incentives for the development of anaerobic
digestion systems have been launched in other countries in
Europe and also elsewhere, such as in USA, Canada and
Australia.
Anaerobic digestion systems in the developed world are seen
as large, expensive to install and run, and needing high-tech
equipment to operate. Much more information is available on
the IEA Task 37 website, especially in a book they have
published: “The Biogas Handbook”.
More information on biogas technology in developing countries
can be found in “Small-scale, Rural Biogas Programmes” and
“Running a Biogas Programme”.
Development of
Biogas Technology