The energy feasibility project has investigated the requirements for energy for two example products – bread and tomato paste and the linkages between energy-water-food.

CO2 is fed back into the greenhouses via pipes.
CO2 is fed back into the greenhouses via pipes to help ripen the tomatoes.

The report has developed local energy system scenarios and evaluated energy generation and storage technologies suitable for implementing the scenarios: efficiency, cost effectiveness, safety, and environmental impact.

The Energy feasibility report is available.

The summary findings are:

An assessment of the likely energy impact of redistributing the manufacture of bread to the local level suggested that moves to more redistributed production would result in a significant increase in the energy required to produce the country’s bread. In addition, there is likely to be a slight increase in emissions under this scenario unless local production was based on the technologies employed in highly energy efficient, larger scale bakeries. It may also be possible to reduce the energy requirements of locally based bakeries through, for example, mini hydro or solar installations, though this would be heavily dependent on sites possessing access to water resources or space for solar panels. Thus, from an energy point of view, RDM would only contribute to reduced demand if it involved the development of highly energy efficient local bakeries and home baking equipment. Whether such a situation could be economically feasible or structurally possible is open to question. This suggests that, from the point of view of energy efficiency and emissions reduction there is at best, a weak case to be made for RDM in the food sector from an energy perspective. Rather the report suggests that different scales produce better energy outcomes for different processes, the question of which scale works best depends on the characteristics of the specific process involved.

The areas identified for future research are as follows:

  • Undertaking a detailed supply chain and energy feasibility study for the tomato paste case similar to the analysis presented for bread in this report.
  • Data collection and further exploration of the potential for symbiotic processes to re-use/optimise energy, water and waste/ waste by-products, such as using wasted energy from other industries in milling and baking processes (e.g. using heat from steam/water from cooling towers in power stations for district heating and local bakeries, using waste heat from bakeries or district heating for milling, potential to capture and store heat from ovens in under-ground water reservoirs to re-use heat and water in other processes/ industries such as nearby tomatoes green-houses, collecting and storing rainwater from green-houses roofs).
  • Study geographical implications of relocating manufacturing facilities (e.g. potential for relocating greenhouses near industries with excess energy losses such as bakery plants).
  • Data collection and further exploration of the potential for ground-source heat pumps (specially ground-sourced heat coils under green-houses), CHPs/biomass, energy from waste, solar, wind and hydro in the milling and bread manufacturing sectors.
  • Data collection and investigation of the operational emissions and potential for emissions reduction if more solar and hydro were used instead of gas or grid-electricity at local level.
  • Investigate energy decentralisation and the role of policy in promoting localised renewable energy sources (e.g. biomass /CHPs, solar, energy from waste, wind, hydro, biogas for villages as exchange for free/cheap electricity)
  • Data collection and investigation of the links between potential for decentralised water treatment plants and links to biogas.
  • Investigate if efficiencies are possible when using hydrogen for cooking at local scale in UK.
  • Further research the implications for energy up and down the full food supply chain (not only focussing in the manufacturing processes, including energy from waste in the studied or other food supply chains).
  • Investigate potential for water re-use, and water and energy nexuses for suitable foods and their full supply chain (e.g. upstream water and energy footprints in agriculture, rainwater harvesting from green-houses, grey water/ effluent recycling and heat storage for processing).
  • Data collection and calculation of energy savings linked to rainwater harvesting and grey water recycling (e.g. for tomatoes -if possible completing information collected from interviews and fieldwork- and other food supply chains).
  • Data collection and study energy savings in relation to economic savings (i.e. savings in emissions and energy bills over a horizon of 20 years if alternative energy sources were used).
  • Data collection and study energy use for bread manufacturing depending on whether flour is milled using domestic and/or small scale local mills (relevant in relation to RDM of bread in the UK if data are available) versus industrial centralised mills.