Founded in 1988, IED is a French independent engineering consultancy firm active in the energy sector: policy and planning, rural electrification, renewable energy and energy efficiency. Services provided cover all the stages of the project cycle in more than 40 countries across Africa, Asia and Europe. In 2011, IED established the sister company IED Invest to develop, finance and operate small renewable energy projects.
Less than 15% of Cambodia’s rural population has access to grid-based electricity. Rural Electrification Enterprises (REE) were set up to develop mini-grid systems and are playing an important role when improving energy access.
However, the REE decentralised mini-grids are mainly based on inefficient diesel gensets leading to very high production cost. Rice husk has been increasingly used over the last years to produce energy for captive uses, but there are only a few examples of biomass gasification for rural electrification worldwide.
The challenges of the Charchuck project were to meet the load fluctuations, to provide a system that enables a reliable 24 hours a day service at a cheaper end user tariff than with fuel, and to find adequate solutions to address wastewater environmental issues.
Cambodia has a very large number of rice mills and there is an excess of husk, which can be harnessed in several provinces. Opportunities are also offered by other biomass resources from rubber and cashew nut plantations, coconut shells or bamboo, among others. Biomass gasification is basically the conversion of solid fuels, like wood and agricultural residues, into a combustible gas. The system installed consists of a gasifier burning the fuel at more than 400°C. Afterwards, it cools the gas, which flows into a gas treatment line that feeds two engines (100% gas and dual fuel) with clean producer gas.
This is the first Cambodian gasifier that includes a water treatment plant to clean the processed water, and function in a closed circuit. A local team has been trained to operate the system and to ensure its maintenance.
IED Invest mobilised funds from its own resources and from the United Nations Industrial Development Organisation (UNIDO) and the Renewable Energy & Energy Efficiency Partnership (REEEP). IED provides technical support, and the company’s local branch CCDE is in charge of site operation and maintenance. Investment costs are between USD 2,000 - USD 3,000/kW installed. The system feeds a local mini-grid, but it could also easily supply power to the national grid in case of extension.
Thanks to the project, service hours were extended from 16 to 24 hours a day, while decreasing the end user tariff by 25%. Increase in capacity, funding of distribution network and tariff reduction resulted in the number of households connected to the mini-grid rising from 400 to 1,100 in the year following to the installation of the biomass gasifier.
Lower cost for improved service represents positive social impacts through income generating opportunities and wider energy service affordability.