KATHMANDU Micro hydro-electric plants linked to a mini-grid offer a cost-effective and renewable option for rural electrification in the hilly and mountainous terrain of Afghanistan and Nepal, say researchers.

For communities located more than ten kilometres away from the nearest grid substation, micro hydro mini-grid technology was found to be cheaper than extending central grid networks or investing in household solar units.

The researchers compared availability, reliability, efficiency and lifecycle costs — together called levelised cost of electricity — of different technological pathways to electricity access, while taking into account environmental impact.

"From many angles — fuel security, technology, resource availability — micro hydro is the best option," said Brijesh Mainali, researcher at the KTH Royal Institute of Technology (KTH) in Stockholm, and lead author of a paper on electrification pathways due to appear in Renewable Energy in September.

Large segments of the rural population — 66 per cent in Nepal and 93 per cent in Afghanistan — do not have electricity. But with many rivers running through the vast, hilly regions of both countries, there is significant potential for micro hydros.

The average 25—50 kilowatt micro hydro plant offers more electrification options than comparable solar units. "Where feasible we should move forward with micro hydro and then only solar if we are to go ahead with the least cost pathway," Mainali told SciDev.Net.
Research on the electrification needs of countries like Nepal and Afghanistan which are heavily dependent on development assistance could improve cost-effectiveness, said Semida Silveira, co-author of the paper and head of energy and climate studies at KTH.

Silveira said micro-hydro could partly answer the question of how to provide electricity quickly and cost-effectively to the 20 per cent of the world’s population that still does not have electricity.

In the last decade of reconstruction, Afghanistan invested heavily in expensive diesel generators for rural electrification, many of which have ceased functioning, explained Mainali.

For Nepal, with over 30 years of experience in micro-hydro development and almost 20 megawatt of installed capacity, the paper offers little that is new, Jagdish Kumar Khoju, community electrification programme manager at the Alternative Energy Promotion Centre (AEPC), told SciDev.Net.

Nepal's energy policy already discourages solar subsidies where micro and small hydropower is financially and physically feasible.

In 2010, the AEPC established a regional centre of excellence in micro hydro to share knowledge and experience with other countries in the region, including Afghanistan.

Link to abstract in Renewable Energy: