Three AQMesh pods have been monitoring air quality in Kenya as part of a study to measure the impact of using biogas as an alternative cooking fuel.
Funded by the UK Research Council and led by a partnership between the University of Cambridge Institute for Sustainability Leadership (CISL) and the Department of Chemistry, the project conducted a pilot study to test whether households using clean biogas technology for cooking experienced improvements in air quality compared to households burning biomass with more traditional technology.
Kenya only has one air quality monitoring station, meaning there is currently almost a total absence of reliable air quality data. Personal exposure and location-specific data is not available, limiting the ability to inform strategies for tackling health problems caused by exposure to poor air quality. In addition to handheld devices for measuring indoor air quality, AQMesh was therefore chosen because of its small size, low power consumption and the ability to be powered using a range of sources.
“Given the limited research infrastructure available to quantify air pollution levels in peri-urban Kenya, this study employed novel sensing technologies that offer an affordable, achievable and validated alternative”, commented Dr Lia Chatzidiakou of the Department of Chemistry, University of Cambridge.
Domestic biodigesters and biogas cooking stoves had been introduced to 50 households within the community prior to this pilot study. Air pollution levels close to houses using the new biogas stoves and the houses using traditional biomass fuels were measured continuously for two months with three AQMesh pods. These were deployed across strategic locations to understand the spatial and temporal variations of the different emission sources, depending on wind speed and direction. 18,000 observations of pollutants were gathered, with a data capture rate of over 90%. Initial analysis focused on fine particulate matter (PM2.5) and carbon monoxide (CO) as an indicator of combustion. Initial conclusions suggest that the level of air pollutants may be determined more by the material being cooked – fish, in this case – than the fuel used but the study also revealed some unexpected benefits of using biogas as a cooking fuel.
Biogas produced within the digester is piped into the household where it is connected to a double-ring stove and ready to burn. The site studied was developed in a manner that is broadly representative of many sub-Saharan settlements: clusters of houses around communal open spaces, with more buildings continually being built. The preliminary report highlights the social benefits of shifting to biogas as a cooking fuel, as well as improvements in air quality, and the possibility of releasing time for women to receive education.
New technology, research and tests can sometimes cause curiosity and concern in many communities, so it was important to allow time to talk to families, and explain the project. On arrival, the Cambridge
team met with householders to answer their questions and discuss their involvement in the research. Local residents were shown the AQMesh pods – this sort of introduction has ensured full cooperation and uninterrupted deployment of monitoring equipment in many such projects.
Prior to their deployment, the AQMesh pods were co-located next to certified reference instruments in the UK (Department of Chemistry, University of Cambridge) to characterise their performance. The three AQMesh pods were also co-located close together at the site in Kenya, demonstrating a high level of precision, as shown in the plots.
As well as this study in Kenya, AQMesh pods are currently operating in a variety of projects across Africa, including Ghana, Rwanda, Botswana, Malawi, Libya, Mauritius and South Africa, and AQMesh has previously been used in Nigeria.