Pig Farming vs. Solar Farming: Exploring Novel Opportunities for the Energy Transition

Abstract

Amsterdam aims to bring down its carbon footprint by 55% in 2030 and by 95% in 2050. For the built environment, plotted pathways towards carbon neutrality primarily revolve around the reduction of fossil based energy demand and the transition towards renewable energy production strategies. The consumption of food resources, and its significant corresponding carbon footprints, remain up to this day outside the scope of the city’s carbon accounting. At the interface of the building sector and the agricultural sector, under-explored possibilities for synergistic and sustainable resource management come to light. For a more holistic and veracious evaluation, this research expands the carbon inventory of the urban dweller with the food category and then explores, by means of a case study, a novel strategy for the decarbonisation of the built environment: urban pig farming in Amsterdam. A theoretical farming system is added to an urban context and coupled with the existing local resource flows, allowing for new output-input links. The capacity of the farm, i.e. the maximum number of animals at any time, is determined by the daily food waste output of the neighbourhood. A comparison is drawn with a conventional method for the energy transition: photovoltaic energy, for which two common array configurations are assessed. The three scenarios are evaluated on three aspects relevant to the energy transition of the built environment: avoided carbon emissions, produced thermal energy and produced electrical energy, normalised per square meter surface area. Carbon accounting shows that an integrated pig production facility of 495 m2, holding 79 animals, can potentially reduce the carbon emissions of Kattenburg by 218 tons (−5.6%) a year, i.e. 441 kg CO2/m2. The solar farm has a net impact of 42 kg/m2/yr if the panel array configuration is based on optimal panel angle and 77 kg/m2/yr if the configuration is based on optimal ground surface area cover. This study intends to spark further discussion on urban farming by showing that an integrated pig farm can potentially avoid between 6–10 times more carbon emissions compared to a solar farm.