From food waste to transport biomethane, a comprehensive scenario-based waste to energy conversion pathway trade-off and whole systems modeling analysis

This thesis outlines the design of a novel methodological, Excel modelling and integrated whole systems analysis approach for elucidating key material, energy and financial cost-benefit trade-off arising from deployment of Food Waste (FW) to Transport biomethane conversion (FWtTBC) pathway across the Northern Powerhouse (NPH) city and metropolitan county regions and more specifically across Leeds city region which embodies a more in-depth case study analysis. To this end, the research established that real-world representative values for household FW collection and FW to biomethane conversion potential (45-90m3) to be sufficient across NPH city and metropolitan county regions to be financially self-sufficient for FWtTBC pathway deployment attributed to key revenue streams against deployment cost.

Here the case-specific scenario study of FWtTBC pathway deployment at NPH Leeds city region using Malting Organics Treatment Facility demonstrated that there exists sufficient AD food waste capacity (50,000 tonnes) to accommodate FW collected from the entire population of Leeds city. Assessment of total revenue against cost of FWtTBC pathway deployment has returned a decent payback period of 2 to 10 years under realistic real-world operational conditions, whilst also having outlined the significant revenue contribution derived from RTFO and avoided FW landfill tax. It is consequently advised for such policies to remain in replace for the foreseeable future.

Moreover, the research established a number of policy recommendations across each relevant chapter that is thought to be effective in mitigating key risk factors that could undermine successful pathway deployment either financially or operationally. Namely, these include policy recommendations to optimize household FW disposal and capture rate, FW supply flexibility
and FW collection logistics in addition to those that endeavour to safeguard RTFC, biomethane sales and avoided FW landfill tax revenues.

Future research should focus on using real-world operational data availability pertaining specifically to FWtTBC pathway deployment across a single or select few regions, which would enable the adopted modelling approach to achieve much greater specificity and accuracy in its intended findings and outcomes. It is hoped for the findings of this and future similar research to be used to support real-world FWtTBC pathway deployment in key regions of need, to help facilitate the actual real-world deployment process at any suitable scale of implementation.