To reduce environmental burdens from the food system, a shift towards environmentally sustainable diets is needed. In this study, the environmental impacts of the Swedish diet were benchmarked relative to global environmental boundaries suggested by the EAT-Lancet Commission. To identify local environmental concerns not captured by the global boundaries, relationships between the global EAT-Lancet variables and the national Swedish Environmental Objectives (SEOs) were analysed and additional indicators for missing aspects were identified. The results showed that the environmental impacts caused by the average Swedish diet exceeded the global boundaries for greenhouse gas emissions, cropland use and application of nutrients by two- to more than four-fold when the boundaries were scaled to per capita level. With regard to biodiversity, the impacts caused by the Swedish diet transgressed the boundary by six-fold. For freshwater use, the diet performed well within the boundary. Comparison of global and local indicators revealed that the EAT-Lancet variables covered many aspects included in the SEOs, but that these global indicators are not always of sufficiently fine resolution to capture local aspects of environmental sustainability, such as eutrophication impacts. To consider aspects and impact categories included in the SEO but not currently covered by the EAT-Lancet variables, such as chemical pollution and acidification, additional indicators and boundaries are needed. This requires better inventory data on e.g., pesticide use and improved traceability for imported foods.

Biodiesel is the main liquid biofuel in the EU and is currently mainly produced from vegetable oils. Alternative feedstocks are lignocellulosic materials, which provide several benefits compared with many existing feedstocks. This study examined a technical process and its mass and energy balances to gain a systems perspective of combined biodiesel (FAME) and biogas production from straw using oleaginous yeasts. Important process parameters with a determining impact on overall mass and energy balances were identified and evaluated. In the base case, 41% of energy in the biomass was converted to energy products, primary fossil fuel use was 0.37 MJprim/MJ produced and 5.74 MJ fossil fuels could be replaced per kg straw dry matter. The electricity and heat produced from burning the lignin were sufficient for process demands except in scenarios where the yeast was dried for lipid extraction. Using the residual yeast cell mass for biogas production greatly increased the energy yield, with biogas contributing 38% of total energy products. In extraction methods without drying the yeast, increasing lipid yield and decreasing the residence time for lipid accumulation are important for the energy and mass balance. Changing the lipid extraction method from wet to dry makes the greatest change to the mass and energy balance. Bioreactor agitation and aeration for lipid accumulation and yeast propagation is energy demanding. Changes in sugar concentration in the hydrolysate and residence times for lipid accumulation greatly affect electricity demand, but have relatively small impacts on fossil energy use (NER) and energy yield (EE). The impact would probably be greater if externally produced electricity were used.