Fredrik Hedenus

Induced technological change in a limited foresight optimization model

The threat of global warming calls for a major transformation of the energy system the coming century. Modeling technological change is an important factor in energy systems modeling. Technological change may be treated as induced by climate policy or as exogenous. We investigate the importance of induced technological change (ITC) in GET-LFL, an iterative optimization model with limited foresight that includes learning-by-doing. Scenarios for stabilization of atmospheric CO2 concentrations at 400, 450, 500 and 550 ppm are studied. We find that the introduction of ITC reduces the total net present value of the abatement cost over this century by 3-9% compared to a case where technological learning is exogenous. Technology specific polices which force the introduction of fuel cell cars and solar PV in combination with ITC reduce the costs further by 4-7% and lead to significantly different technological solutions in different sectors, primarily in the transport sector.

Trends in greenhouse gas emissions from consumption and production of animal food products - implications for long-term climate targets

To analyse trends in greenhouse gas (GHG) emissions from production and consumption of animal products in Sweden, life cycle emissions were calculated for the average production of pork, chicken meat, beef, dairy and eggs in 1990 and 2005. The calculated average emissions were used together with food consumption statistics and literature data on imported products to estimate trends in per capita emissions from animal food consumption. Total life cycle emissions from the Swedish livestock production were around 8.5 Mt carbon dioxide equivalents (CO2e) in 1990 and emissions decreased to 7.3 Mt CO2e in 2005 (14% reduction). Around two-thirds of the emission cut was explained by more efficient production (less GHG emission per product unit) and one-third was due to a reduced animal production. The average GHG emissions per product unit until the farm-gate were reduced by 20% for dairy, 15% for pork and 23% for chicken meat, unchanged for eggs and increased by 10% for beef. A larger share of the average beef was produced from suckler cows in cow-calf systems in 2005 due to the decreasing dairy cow herd, which explains the increased emissions for the average beef in 2005. The overall emission cuts from the livestock sector were a result of several measures taken in farm production, for example increased milk yield per cow, lowered use of synthetic nitrogen fertilisers in grasslands, reduced losses of ammonia from manure and a switch to biofuels for heating in chicken houses. In contrast to production, total GHG emissions from the Swedish consumption of animal products increased by around 22% between 1990 and 2005. This was explained by strong growth in meat consumption based mainly on imports, where growth in beef consumption especially was responsible for most emission increase over the 15-year period. Swedish GHG emissions caused by consumption of animal products reached around 1.1 t CO2e per capita in 2005. The emission cuts necessary for meeting a global temperature-increase target of 2° might imply a severe constraint on the long-term global consumption of animal food. Due to the relatively limited potential for reducing food-related emissions by higher productivity and technological means, structural changes in food consumption towards less emission-intensive food might be required for meeting the 2° target.

Climate metrics and the carbon footprint of livestock products: where’s the beef?

The livestock sector is estimated to account for 15% of global greenhouse gas (GHG) emissions, 80% of which originate from ruminant animal systems due to high emissions of methane (CH4) from enteric fermentation and manure management. However, recent analyses have argued that the carbon footprint (CF) of ruminant meat and dairy products are substantially reduced if one adopts alternative metrics for comparing emissions of GHGs-e.g., the 100 year global temperature change potential (GTP(100)), instead of the commonly used 100 year global warming potential (GWP(100))-due to a lower valuation of CH4 emissions. This raises the question of which metric to use. Ideally, the choice of metric should be related to a climate policy goal. Here, we argue that basing current GHG metrics solely on temperature impact 100 years into the future is inconsistent with the current global climate goal of limiting warming to 2 degrees C, a limit that is likely to be reached well within 100 years. A reasonable GTP value for CH4, accounting for current projections for when 2 degrees C warming will be reached, is about 18, leading to a current CF of 19 kg CO2-eq. per kilo beef (carcass weight, average European system), 20% lower than if evaluated using GWP(100). Further, we show that an application of the GTP metric consistent with a 2 degrees C climate limit leads to the valuation of CH4 increasing rapidly over time as the temperature ceiling is approached. This means that the CF for beef would rise by around 2.5% per year in the coming decades, surpassing the GWP based footprint in only ten years. Consequently, the impact on the livestock sector of substituting GTPs for GWPs would be modest in the near term, but could potentially be very large in the future due to a much higher (>50%) and rapidly appreciating CF.

Diet-related greenhouse gas emissions assessed by a food frequency questionnaire and validated using 7-day weighed food records.

BackgroundThe current food system generates about 25 % of total greenhouse gas emissions (GHGE), including deforestation, and thereby substantially contributes to the warming of the earth’s surface. To understand the association between food and nutrient intake and GHGE, we therefore need valid methods to assess diet-related GHGE in observational studies.MethodsLife cycle assessment (LCA) studies assess the environmental impact of different food items. We linked LCA data expressed as kg carbon dioxide equivalents (CO2e) per kg food product to data on food intake assessed by the food frequency questionnaire (FFQ) Meal-Q and validated it against a 7-day weighed food record (WFR). 166 male and female volunteers aged 20–63 years completed Meal-Q and the WFR, and their food intake was linked to LCA data.ResultsThe mean GHGE assessed with Meal-Q was 3.76 kg CO2e per day and person, whereas it was 5.04 kg CO2e using the WFR. The energy-adjusted and deattenuated Pearson and Spearman correlation coefficients were 0.68 and 0.70, respectively. Moreover, compared to the WFR, Meal-Q provided a good ranking ability, with 90 % of the participants classified into the same or adjacent quartile according to their daily average CO2e. The Bland-Altman plot showed an acceptable level of agreement between the two methods and the reproducibility of Meal-Q was high.ConclusionsThis is the first study validating the assessment of diet-related GHGE by a questionnaire. The results suggest that Meal-Q is a useful tool for studying the link between food habits and CO2e in future epidemiological studies.

Nuclear power as a climate mitigation strategy - technology and proliferation risk

Recent years have witnessed renewed interest in nuclear power in large extent due to the need to reduce carbon emissions to mitigate climate change. Most studies of cost and feasibility of stringent climate targets that include nuclear power focus on the currently available light water reactor (LWR) technology. Since climate mitigation requires a long-term commitment, the inclusion of other nuclear technologies such as mixed oxide-fuelled LWRs and fast breeder reactors may better describe the future energy supply options. These different options also entail different nuclear weapon proliferation risks stemming from uranium enrichment or reprocessing of spent fuel. To investigate this relation, we perform a scenario analysis using the global energy transition model. Our results indicate that meeting a scenario with a 430 ppm CO2 target for 2100 is feasible without the involvement of nuclear power; however the mitigation costs increase by around 20%. Furthermore, a lasting contribution by nuclear power to climate change mitigation can only be achieved by alternative fissile material production methods and global diffusion of nuclear technologies. This in turn bears important implications for the risk of nuclear proliferation for several reasons. First, knowledge and competence in nuclear technology becomes more accessible, leading to the risk of nuclear programmes emerging in states with weaker institutional capacity. Additionally, even if the reprocessing step in a fast breeder cycle proves to be essentially proliferation resistant, the build-up of breeder reactor systems necessitates a long transition period with large-scale use of enrichment technology and its related proliferation risks. Our study does not include the costs posed on society by nuclear accident risk and by the need to upscale safeguards and regulatory capacity to deal with increased proliferation risk.

Scenario development as a basis for formulating a research program on future agriculture: a methodological approach.

To increase the awareness of society to the challenges of global food security, we developed five contrasting global and European scenarios for 2050 and used these to identify important issues for future agricultural research. Using a scenario development method known as morphological analysis, scenarios were constructed that took economic, political, technical, and environmental factors into account. With the scenarios as a starting point future challenges were discussed and research issues and questions were identified in an interactive process with stakeholders and researchers. Based on the outcome of this process, six socioeconomic and biophysical overarching challenges for future agricultural were formulated and related research issues identified. The outcome was compared with research priorities generated in five other research programs. In comparison, our research questions focus more on societal values and the role of consumers in influencing agricultural production, as well as on policy formulation and resolving conflicting goals, areas that are presently under-represented in agricultural research. The partly new and more interdisciplinary research priorities identified in Future Agriculture compared to other programs analyzed are likely a result of the methodological approach used, combining scenarios and interaction between stakeholders and researchers.

Policy Strategies for a Sustainable Food System: Options for Protecting the Climate

How to raise livestock--and how not to / Colin Tudge -- The water footprint of animal products / Arjen Hoekstra -- Livestock and climate change / Tara Garnett -- Industrial livestock production and biodiversity / Susanne Gura -- Does organic farming offer a solution? / Richard Young -- Food from the dairy--husbandry regained? / John Webster -- Cracking the egg / Ian Duncan -- Cheap as chicken / Andy Butterworth -- Sustainable pig production : finding solutions and making choices / Alistair Lawrence and Alistair Stott -- Industrial animal agricultures role in the emergence and spread of disease / Michael Greger -- Environmentally sustainable and equitable meat consumption in a climate change world / A.J. McMichael and Ainslie Butler -- How much meat and milk is optimal for health? / Mike Rayner and Peter Scarborough -- Developing ethical, sustainable and compassionate food policies / Kate Rawles -- Religion, culture and diet / Martin Palmer -- Policy strategies for a sustainable food system: options for protecting the climate / Stefan Wirsenius and Fredrik Hedenus -- Meat and policy : charting a course through the complexity / Tim Lang, Michelle Wu and Martin Caraher -- Confronting policy dilemmas / Jonathon Porritt.In this chapter we argue that in order to substantially reduce greenhouse gas (GHG) emissions from food production and to preserve natural and agricultural biodiversity, policies that separately address the demand and the supply sides of the food system will be required. Taxes on animal food, and other policies that shift consumption patterns towards less GHG intensive and land-demanding food, will be crucial for reducing agricultural GHG emissions as well as for mitigating biodiversity losses related to the expansion of agriculture into natural ecosystems. Demand-moderating policies are vital because of the overall low potential for reducing agricultural GHG emissions by technological means, and because of the inherently large land requirements of ruminant meat (beef and lamb) production. However, demand-side policies alone are far from enough. Comprehensive supply-side policies will also be required, especially for containing agricultural land expansion in order to protect biodiversity in tropical regions. Supply-side policies, such as direct subsidies, will also be fundamental for preserving agricultural-related biodiversity in Europe and other regions holding biodiversity-rich permanent pastures. The latter holds for Europe even if no policies that moderate the demand for ruminant meat are put in place, since the low-intensive land use characteristic of these areas in either case is not economically viable in the long run. Furthermore, the biodiversity rich areas represent a minor share of the total agricultural land in Europe. Therefore, the goal to preserve agricultural biodiversity in Europe should not be taken as a counter-argument against reducing global ruminant meat production by the implementation of demand-moderating policies.

Adherence to dietary recommendations for Swedish adults across categories of greenhouse gas emissions from food

OBJECTIVE To explore associations between diet-related greenhouse gas emissions (GHGE), nutrient intakes and adherence to the Nordic Nutrition Recommendations among Swedish adults. DESIGN Diet was assessed by 4d food records in the Swedish National Dietary Survey. GHGE was estimated by linking all foods to carbon dioxide equivalents, using data from life cycle assessment studies. Participants were categorized into quartiles of energy-adjusted GHGE and differences between GHGE groups regarding nutrient intakes and adherence to nutrient recommendations were explored. SETTING Sweden. SUBJECTS Women (n 840) and men (n 627) aged 18-80 years. RESULTS Differences in nutrient intakes and adherence to nutrient recommendations between GHGE groups were generally small. The dietary intake of participants with the lowest emissions was more in line with recommendations regarding protein, carbohydrates, dietary fibre and vitamin D, but further from recommendations regarding added sugar, compared with the highest GHGE group. The overall adherence to recommendations was found to be better among participants with lower emissions compared with higher emissions. Among women, 27 % in the lowest GHGE group adhered to at least twenty-three recommendations compared with only 12 % in the highest emission group. For men, the corresponding figures were 17 and 10 %, respectively. CONCLUSIONS The study compared nutrient intakes as well as adherence to dietary recommendations for diets with different levels of GHGE from a national dietary survey. We found that participants with low-emission diets, despite higher intake of added sugar, adhered to a larger number of dietary recommendations than those with high emissions.