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Large quantity of manure is generated in the livestock industry in British Columbia (BC) and natural gas is being consumed intensively in BC’s agriculture sector. We proposed to integrate the livestock farms and the greenhouses to promote waste-to-energy and waste-to-material exchanges following the principles of Industrial Ecology (IE). Natural gas consumptions on farms are replaced by renewable biogas generated from anaerobic digestion (AD) of farm wastes (mainly livestock manure). CO₂ for plant enrichment in greenhouses is supplied by biogas combustion flue gases and the residues (digestate) from digesters are used as animal bedding materials, plant growing media, and liquid fertilizers. An integrated dairy farm and greenhouse was first modeled. Co-digestion of manure with a variety of organic farm wastes was further evaluated with an aim to enhance the biogas production. To address the problems of too much digestate surplus and high CO₂ demand for greenhouse CO2 enrichment, the mushroom farm was further introduced into the integrated system. In this way, the digestate surplus can be used as a growing media for growing mushrooms and the CO₂–rich ventilation air from the mushroom can be directed to the greenhouse for CO₂ enrichment. A Life Cycle Analysis (LCA) was conducted to quantify the environmental impacts of each of the proposed cases in comparison to the conventional agriculture practices. The LCA results showed that the integrated dairy farm-greenhouse system reduces non-renewable energy consumption, climate change, acidification, respiratory effects from organic emissions, and human toxicity by more than 50% compared to conventional operations; among which the reductions in non-renewable energy consumption, climate change, and human toxicity are the most significant. If the digestate surplus is treated as a waste, the integrated system has a ~20% increase in eutrophication and respiratory effects from inorganic emissions. When other organic wastes are codigested with dairy manure, all the impacts can be further reduced in all cases. If a mushroom farm is introduced to form an integrated dairy farm-greenhouse-mushroom farm system, a large greenhouse can be facilitated and the digestate can be largely reused; thus all the analyzed impacts are significantly reduced compared to the base scenario.

As part of its commitment towards engaging in sustainability best practices, UBC Athletics & Recreation commissioned the UBC Centre for Sport and Sustainability to carry out a pilot study of the climate change impacts of a varsity ‘Thunderbirds’ basketball event. The UBC Life Cycle Assessment Alliance, a cross-faculty collaboration of UBC grad students applying LCA in a variety of fields, measured impacts for the most significant event organizational sectors: travel, accommodation, food, materials and waste, venue operation and infrastructure. A key aim of this study was to apply rigorous evaluation methods in a resource-efficient manner that estimated major impacts by using easily obtainable activity data. A hybrid LCA method combining both input-output and unit process data was applied to measure climate change potential. The unit of analysis was all services that went into providing an entertainment experience for participants over the four-hour period of the event (food, warmth, transport, safety, etc.). The results showed a total of approximately 5 tonnes of carbon dioxide equivalents from the five event sectors under study. The major impact came from travel (73%), followed by food & beverage (12%), accommodation (11%), venue operation and infrastructure (3%), and materials & waste (1%). A sensitivity analysis showed that the travel impacts of this event were actually significantly lower than an average UBC basketball event since the visiting team came by bus whereas most events require travel by air. This report includes recommendations for GHG mitigation opportunities for future editions of this event. It also recommends that a robust baseline for all UBC A&R events be developed to set specific targets and measure performance. A more comprehensive sustainability management system that addresses other environmental, social and economic issues is also recommended.