Waste to value with biogas in Nepal

Nepal is currently experiencing a combined economic-ecological crisis: rising petroleum imports and a deteriorating environment.

Urban municipal waste management is a pressing issue, even though there is inadequate understanding of waste as a resource puts pressure on landfills and the environment.

Given that more than half of Nepal’s municipal garbage is biodegradable, generating Bio-CNG in digesters could be the answer to energy self-sufficiency and sustainability. This is a win-win-win: it improves the urban environment, reduces carbon emission and slashes the trade deficit by substituting LPG and chemical fertiliser use. 

Domestic scale biogas technology is one of Nepal’s success stories in the past three decades. The family-level plants offer cooking solutions for more than 0.3 million rural households. However, with growing concern about organic waste management and increasing demand for clean energy, large-scale biogas technology has been gaining traction in recent years.

The government with support from development partners has been exploring the possibility of scaling up the biogas technology and supporting the private sector, factories and municipalities for the installation of large-scale biogas plants.

There are now 344 large-scale biogas plants in the country, but only a few of them have digesters larger than 3,000 cubic meters, considered a threshold for being commercially viable.

These biogas plants primarily utilise biodegradable municipal solid waste, livestock manure and poultry litter as feedstock. After purification, the biogas can be used as an alternative to cooking and transportation fuel.

A recent waste management baseline survey of Nepal indicates that urban municipalities in Nepal generate nearly 2,400 metric tons per year of solid waste on average, more than half of which is organic. This means that almost 10,000 metric tons of purified biogas (bio-CNG) with more than 90% methane concentration can theoretically be produced in the municipalities.

An additional 1.5 million metric tons of bio-CNG per year could be generated using livestock manure across the country. Even if we could use only 10% of this waste, we could still generate nearly 145,000 metric tons of bio-CNG per year — equivalent to more than 10 million LPG cylinders — and help reduce Nepal’s LPG imports by 30%, narrow the trade gap with India and save foreign currency.

Furthermore, the spent effluent from the digesters as a by-product of biogas plants could substantially reduce Nepal’s imports of chemical fertiliser, and promote organic farming.

Using bio-CNG generated from waste as cooking fuel would save more than 2.8 million tons of carbon dioxide equivalent of greenhouse gases. Large-scale biogas plants have the potential to fulfil two of the country's most pressing needs: effective organic waste management and clean energy supply.

The availability of waste as raw materials as well as the urgency for a sustainable waste management model creates a huge opportunity for Nepal. But the development of large-scale biogas systems have been hampered by unfavourable government policies, techno-economic and institutional challenges.

For example, the Environment protection rule (2020) stipulates that the  installation of a biogas plant larger than 1,500 cubic metres requires an environmental impact assessment. Gandaki Urja, a Karki-based private sector biogas developer that produces bio-CNG and fertiliser from farm waste, took more than a year to obtain environmental approval.

Similarly, even with government subsidies, the CAPEX for large-scale biogas technology is costly, making private sector project developers unwilling to invest. There is also a lack of skilled human resources for the operation and maintenance of large-scale biogas.

Likewise, we need to import spare parts, machinery, and equipment for the establishment of a biogas plant. The process takes time and impedes the projects’ timely installation and smooth operation. Feedstock supply can also be erratic.

There is a need to ensure a technology supply chain (production, distribution and after sales service). Periodic training and follow-up through the Council for Technical Education and Vocational Training (CTEVT) could create the necessary expertise.

The development of adequate skilled human resources through a tripartite collaboration among government, industry and academia for applied research in biogas systems is also key to ensure sustainability in the large-scale biogas sector.

Both the government and private project developers should set aside funds to boost research into commercial biogas systems. Likewise, an awareness program to sensitise consumers about its environmental and economic benefits, knowledge transfer and training could reduce the uncertainty and encourage consumers to use bio-CNG.

Government support in the biogas sector through policy measures like reducing pollution from livestock farms and agro-processing industries, a ban on the disposal of municipal solid waste dumping in landfill sites, enforcement of strict waste management rules, and encouraging waste segregation at the source can be pivotal.

The way ahead for energy sufficient Nepal is setting realistic targets for biogas production with appropriate planning and strategies for large-scale biogas development.

The partnership between the government and private sectors will also increase the uptake of biogas as well as increase the demand for large-scale biogas plants which can save both our ecology and economy.

Sushmita Dulal is the manager at WindPower Nepal.