BSF larvae economic potential
One of the key questions for us in taking the idea of using Black Soldier Fly (BSF) larvae forward was whether or not the value that could be recovered from BSF-derived products would be sufficient to drive a lower-cost – or even free – emptying service for latrine users. In other words, would a business producing BSF products from latrine waste be viable economically? We needed to make sure there was a business case for using these larvae to transform latrine sludge into a product or products capable of supporting latrine emptying and waste collection operations.
We asked a team of MBA students from the International Business Development Team at the Haas School of Business, UC Berkeley, to explore this question. Using Tanzania as their research area, the team examined the operational and economic feasibility of an independent, for-profit, entrepreneur-owned business, as well as the risks and challenges associated with its implementation.
How would a business work?
The team envisaged that such a business would grow and develop BSF larvae through feeding them on pit latrine contents. The material would be extracted from latrines and transported to a central processing facility, where the larvae would be introduced. These take roughly 10 days to mature, depending on climate and access to feed, after which the larvae naturally seek to move away from their food source in order to find an adequate pupation site. This self-harvesting aspect is particularly conducive to larger-scale waste processing operations, where individual pre-pupae collection would be unfeasible. Once harvested, the larvae can be sterilised and processed in a number of ways to generate several different end products, such as high-protein animal feed or an oil feedstock for biodiesel production.
Finding successful models
The team’s aim was to understand whether such a business would generate sufficient revenue to sustain a free latrine emptying service for users. Their study took a three-pronged approach:
- market analysis for biodiesel and chicken feed in Tanzania
- analysis of the operational requirements needed to bring the end product to market including labour, capital expenditure and process flows
- the creation of a financial model, including estimates for fixed and variable operational costs, in addition to revenue.
On this basis, the team developed and evaluated three different possible solutions which were examined financially (read their full report here). Through their interviews, secondary source research and financial modelling, they showed that two of these scenarios, based on the assumptions made, would be profitable and would cover the costs of emptying and collecting waste. So this type of business does hold the potential to address one of the key problems for latrine users concerned about pit filling: anxiety about paying for emptying.
What does this mean for our innovation?
These findings are an exciting encouragement to continue our BSF research, carried out at LSHTM, into the potential of this approach to improve sanitation. They give us the green light to start working towards the pilot stage for this approach and consider how scalable it is likely to be. We also need to learn much more about the development potential of BSF larvae on latrine waste. Although the Haas team focused on Tanzania, they suggested that their business models could apply equally well in other countries, as long as certain factors are considered:
- whether BSF is native (it may be difficult to get permission to introduce a new species)
- government policies on waste management, biodiesel and animal feed
- market prices and demand for biofuel and feed
- consumer perception (are people willing to use BSF-related products in biodiesel or animal feed, and consume chickens fed on larvae grown from human waste?)
- population density (if too thin, it may be logistically difficult to collect enough waste to make operations viable).
Once these considerations have been taken into account, the Haas financial model could be applied as an assessment tool to identify pilot locations for a BSF-based business.
Please get in touch if you can help in our research or are interested in helping commercialise this novel approach to providing good sanitation for people in developing countries.