Table: Comparison of Sanivation briquettes to wood and charcoal

Case Study 4-34: Solid Fuel Briquettes as a Reuse Product in Kakuma, Kenya78

Sanivation has developed a briquette production system for human waste and it is used in Kakuma, Kenya. Treated faeces has a high energy content and can be utilized as a biomass fuel like charcoal and wood. In the Sanivation system the faeces act as a binder for other biomass waste streams such as charcoal dust, agricultural residues, and carbonized prosopis (a woody invasive weed in East Africa).

Treated faeces mixed with crushed high-carbon co-waste (other bio-mass as above) at a ratio of around 10-30% wet faecal sludge by mass. Water is added as required to produce the required consistency for mixing and pressing. When it reaches the required consistency, it is transferred to a roller press, which presses the mixture into briquettes. Pressed briquettes are spread onto drying racks and dried in the sun for 3 days. The briquettes are checked in quality control process for burn time, water boiling time, and resistance to breaking when dropped from a height of 1 meter.

Figure: Small-scale treatment and reuse system comprising of treatment tank, mixer, roller press, drying beds and burning briquettes. Figure: Small-scale treatment and reuse system comprising of treatment tank, mixer, roller press, drying beds and burning briquettes.

78 Sanivation and UNHCR. Container-based Toilets with Solid Fuel Briquettes as a Reuse Product, Best Practice Guidelines for Refugee Camps (2018). Available at: https://data2.unhcr. org/en/documents/download/64297 (Accessed: 12/02/2022). Sanivation briquettes have been shown to have a calorific value higher than wood and with less smoke emissions than charcoal.

Table: Comparison of Sanivation briquettes to wood and charcoal.

Charcoal Wood Sanivation briquettes Calorific value 29 MJ/kg 15 MJ/kg 22 MJ/kg

Burning time 3 Hours 1 Hour 4.5 Hours

Emissions (CO ppm) 118 ppm N/A 82 ppm

Emissions (PM2.5 ppm) 213 ppm N/A 196 ppm

In Kakuma briquettes are sold for US$0.20 per kg which is equvilent to the cost of charcoal. The cost per year was estaimated at US$172 per year per houshold and revenue at US$210.

Case Study 4-35: Small-scale desludging equipment

Compact Vacutug carts were introduced into multiple low-income communities around Africa and South East Asia in the early 2000’s by UN Habitat79. The Vacutug technology can be implemented in high-density communities and informal settlements where roads are narrow; the carts are highly manoeuvrable and can be used to access hard-to-reach septic tanks and pit latrines which can often be inaccessible to large desludging machines80 .

Vacutugs implemented in Dar es Salaam, Tanzania, emptied 877 pits with an average of four per day during the first 12 months of operation; this generated a profit of US $700 during the same period. Prior to their implementation a field survey found that residents were willing to pay up to KES 250 per extraction.

4.5.3 Project 16: Water Supply for Low-income Households and Rural Communities

Project Overview

There is a considerable water shortage in Wote. Currently the average distance to water sources across the County is around 5km, this distance is greater in many rural communities. It is often the role of the women or girls to collect water, taking up time that could be spend on school, family or income generation.

Droughts are becoming more frequent as a result of climate change and urbanisation. Unreliability of water sources has led to rationing and interruptions to the public water supply, resulting in many people having to rely on water vendors who supply expensive and untreated water.

An ongoing AfDB funded water supply project will supply 800 m3/day to the piped water system in Wote Municipality and is expected to be completed by the end of 2022. The project scope includes the construction of river intake, treatment works, 30 km pipe network within Wote Town, 1,000 consumer connections and a solar farm to provide operational power. This project proposes that the water company considers subsidising last-mile connections or developing a loan system to support low-income households to connect to the piped water supply system. This will ensure that low-income households benefit from the AfDB Project described above. This will provide increased water capacity in Wote Town, as well as increased connections to the network, in the short term before the development of the water supply from Thwake dam is complete. In addition to this, it is recommended that the water company also provides additional water kiosks in rural communities where distances to sources of water is often greater then in urban areas. In this type of kiosk system, the water company supplies bulk water (at a reduced cost) to the kiosk owner, who then sells it on at an agreed affordable rate to consumers in the area. This creates employment for the kiosk operator and provides a clean water supply close to people’s homes. The kiosk owner could also sell other goods, such as sanitary products, household and cleaning supplies as well as food and beverage. Careful consideration should be given to the location of the proposed new kiosks in order to maximise their benefits for low income and underserved communities particularly in rural areas. Furthermore, supplies of water to the kiosks will need to be carefully managed during the dry season in order to ensure there is a sustainable supply of water available to people who need it the most. The kiosks should be metered to reduce wastage of water.

The proposed water kiosks should incorporate streetlighting, step free access, visual contract to increase visibility of structures and services for the visually impaired, well-designed, legible signage and benches to allow elderly people and women to rest before traveling back home with water canisters. These measures will increase accessibility of the water kiosks at different times of day for women, elderly people and PWDs. However, in some cases PWDs will experience challenges accessing and carrying water back to their homes, therefore, the water company should consider alternative initiatives such as greatly subsiding home connections for PWDs.

79 UN Habitat, Sanitation – Vacutug (2021), Available at : https://mirror.unhabitat.org/ categories.asp?catid=548, (Accessed: 02/12/2021). 80 Engineering for change, The Vacutug (2021), Available at: https://www. engineeringforchange.org/solutions/product/the-vacutug/ , (Accessed: 02/12/2021).