Wood gasifier based 100% gas engine based power plant being tested at Gual Pahari before dispatching to field site

Provision of electricity in the remote rural areas has emerged as a major development priority in India. There are more than 96 000 unelectrified villages and less than 45% of 138 million households in 583 000 villages use electricity for lighting. The economies of electrification of remote rural areas based on grid extension are generally unfavourable, mainly due to high costs involved in grid extension and higher grid losses coupled with small loads and low tariffs.

Out of these unelectrified villages, Government of India has identified 25 000 villages, as remote and difficult to access. For these unelectrifiable villages, decentralized power generation systems are desirable. Electricity needs of these villages are generally in the range of 5-25 kW depending upon the size of the villages. It has been proposed that these villages should be electrified through renewable energy sources (e.g. biomass, small hydro, solar PV, etc.).

Among various renewable energy sources, solar PV is technically mature but the initial costs are very high. Small hydro systems are comparatively cheaper, but these are site specific and the power generating capacity fluctuates seasonally. In this scenario, small-decentralized biomass gasification based power plants emerge as an attractive option for rural electrification provided biomass could be managed locally in a sustainable manner.

Till now, in India, dual fuel engine gensets have been used for producing electricity and utilizing producer gas (produced through gasification) for small-scale decentralized power generation. In a dual fuel system, diesel is required for pilot ignition. Up to 70% of the diesel required can be replaced with producer gas. Due to the high cost of diesel and the problems faced for ensuring its continuous supply to remote villages, the dual fuel system has limited use in rural electrification.

Project strategy
TERI, GV (Gram Vikas) and SDC (Swiss Agency for Development and Cooperation) had been exploring possibilities of application of biomass gasification technology for rural end-uses. A collaborative project “LIBERA” (Livelihood Improvement through Biomass Energy in Rural Areas) was initiated. The main theme of LIBERA was to bring biomass back on center stage as a fuel to boost rural growth and to achieve sustainable development in energy starved remote rural areas. The technology selected here is 100% producer gas engine based biomass gasifier power plant. The aim is to provide decentralized electricity by harnessing locally available biomass in a sustainable manner. The main features of LIBERA concept are shown in Figure 1.

LIBERA (Livelihood Improvement through Biomass Energy in Rural Areas) framework

The project not only aimed at providing electricity for meeting basic requirements for lighting and drinking water, but also to demonstrate a model of livelihood improvement in remote areas through sustainable exploitation of biomass as energy source. The project proposed sustainable biomass supply through community owned energy plantations.

TERI’s role was to provide technical assistance to GV in providing technological solution/option/tool in the form of biomass gasifier-based power generation system, while implementing the LIBERA concept. The first requirement was to develop a more rugged and reliable system through long duration performance monitoring before taking it to GV for field-testing.

Therefore, it was decided that the proposed project would be divided into different phases.
Develop and test small 100% gas based power gasifier system for its long duration performance and reliability
Field-testing at GV and technology transfer for promotion in rural areas of India
Providing technical back-up support to field installations and evolving technological packages for large-scale promotion of small capacity gasifier-based power generating systems through fine-tuning