Dr Daniel Driscoll

Alkaline anion-exchange membranes (AAEMs) are being developed for metal-cation-free solid alkaline fuel cells. Reduced solvent uptakes were observed after immersion in methanol, ethanol and ethylene glycol relative to a Nafion®-115 proton-exchange membrane (PEM); this translated directly into lower alcohol permeabilities. Alkaline polymer electrolytes showed lowered degrees of swelling (membrane thickness), when immersed in methanol and ethanol, relative to Nafion-115. The open circuit voltages, VOCV, of the corresponding direct alcohol fuel cells were superior to acid equivalents with membranes of identical fully hydrated thicknessess; this is indicative of a combination of reduced alcohol permeabilities and changed electrokinetics on PtRu anode catalysts at high pH. VOCV values for the AAEM-DAFCs were higher with ethanol than with methanol (consequent on lower permeability to ethanol), but were lower with ethylene glycol. Promisingly, and contrary to Nafion equivalents, peak power densities were not reduced when C2 alcohols (C-C bond containing) replaced methanol.

Purpose: Rearing crickets in the UK for the live pet food market is already a well-established industry. However, there is interest in also producing food for human consumption. This paper presents a life cycle assessment (LCA) of a current live pet food business. Using results from this LCA, the papers explores how current business practices could be improved to reduce environmental impacts, and discusses the potential benefits of a hybrid live pet food/human consumption business model. Methods: An attributional, cradle-to-farm-gate life cycle assessment was conducted on rearing crickets for the live pet food market, with data collected on-site at a case study business. Results are reported in multiple impact categories from the ILCD 2011 Midpoint+ method. Comparison is made to the only other similar study: an LCA of rearing crickets in Thailand for human consumption (Halloran et al. 2017). The sources of the different environmental impacts between the two studies are explored and inefficiencies in the live pet food rearing process identified. Subsequently, scenarios are used to explore how the inefficiencies may be mitigated, and environmental impact of the live pet food production process reduced through adoption of a hybrid live pet food/human food production model. Results and Discussions: The environmental impact was found to be larger across all impact categories than the only known comparable study, which is for rearing crickets in Thailand for human consumption (Halloran et al. 2017). Some of this difference is due to the heating required for rearing crickets in a climate such as the UK, and some is due to the requirements of the live pet food market being much more demanding on resources than the human food model. The current study identifies improvements in practices that would make this contrast less stark, such as optimizing feeding practices, and the benefits of moving to a hybrid live pet food/human consumption business model. Conclusions: This is the first LCA of crickets reared in the UK. The results highlight inefficiencies in the rearing process that are now being addressed by the case study business. The study also shows the potential co-benefits of a hybrid business model, in which crickets for human consumption are produced alongside crickets for the live pet food market.