Composting municipal solid waste for agriculture in Northern Ghana : rural farmers' willingness to pay for compost quality and access attributes

While farmers in rural areas of northern Ghana find it difficult to obtain sufficient organic soil amendments to keep their soil healthy, there is not enough demand for city compost factories attempting to clean cities of organic solid waste to sustain the composting rate at waste-clearing levels. In this study, 398 farmers in rural communities were surveyed in order to estimate the willingness-to-pay for different quality and access attributes of municipal solid waste (MSW) compost and examine how demand for it can be boosted among such farmers. Several specifications of the generalized multinomial logit (G-MNL) model, using farmers’ choice data, revealed that the compost quality and market access attributes surveyed in the study significantly affect farmers’ decision to buy MSW compost. The results also showed that preferences for the attributes vary widely among the farmers, mainly due to some unobserved personal factors. On average, the empirical estimates indicate that for a 50 kg compost bag, farmers are willing to pay GHS 9.43 for brand/label, GHS 5.76 for pelletized compost, GHS 4.49 for delivery in the community, and GHS 2.49 for sales when they have their cash windfall. Farmers face an average disutility of at least GHS 33.36 for deciding not to buy compost, regardless of its attributes, indicating that besides the attributes captured by the study, other factors important to farmers influence their purchase decisions. Significantly discounted prices together with improved compost quality increase the probability of compost purchase. Thus, overall the findings highlight the need to subsidize MSW compost by more than 50 per cent, to sell it in pelletized form and branded/labelled packages while making it accessible to rural farmers during their cash windfall.