Consumer perceptions of the co-benefits of biosolids and carbon sequestration in a fertiliser aimed at the urban retail market

New markets for biosolids-derived products are urgently required to provide cost-effective solutions for water utilities to address the increasing production of municipal sewage waste. One potential outlet for biosolids is the domestic retail fertiliser market. Biosolids-derived fertilisers could be marketed to consumers by highlighting their environmental benefits, including carbon sequestration potential. This study used a two-part research approach to assess the feasibility of biosolids-derived fertiliser in the current market and to gauge the extent to which retail consumers value carbon sequestration features in fertilisers. First, a hedonic price analysis of existing fertilisers in the market explored consumer preferences and whether they currently pay extra for "sustainable" or "organic-certified" products. Second, a discrete choice experiment was designed to elicit consumers' willingness-to-pay for biosolids-derived fertilisers and those clearly labelled with their carbon sequestration capability. The hedonic price analysis determined that organic or natural fertilisers sell at similar or slightly higher prices than synthetic alternatives. The choice experiment revealed that consumers would pay 17% more for fertilisers labelled with their carbon capture capacity. Purchasers of organic fertilisers perceived biosolids-derived fertilisers as valuable organic alternatives. In contrast, buyers of synthetic fertilisers were willing to pay slightly less for biosolids-derived alternatives. These findings suggest that some consumers are willing to purchase biosolids-derived fertilisers at prices comparable to current alternatives and place higher value on fertilisers offering environmental benefits, such as carbon sequestration. These results indicate that urban retail markets could be a strategic outlet for biosolids by producing biosolids-derived fertilisers.