The environmental footprint: a method to determine the environmental impact of agricultural production

The environmental impact of producing agricultural commodities is an increasingly important topic at a time when climate change, an increasing population and competing demands for food, fibre and fuel are placing heavy demands upon the environment. There are already various methods available for quantifying environmental impact; however, none of them are flexible enough to account for multiple indicators while producing a simple, easy to comprehend result. Life cycle assessment (LCA) can be used to quantify every aspect of a production process and in agriculture has proved valuable in quantifying the inputs and outputs of resources and pollutants that are associated with the production of food commodities. However, the amount of detail that makes the LCA such a valuable tool can also make the results difficult to interpret. Carbon dioxide equivalents (carbon footprints) can be used to quantify the greenhouse gases emitted during a production process and have the advantage, in comparison to the LCA, of presenting the results as a single figure. This approach, as used in the forthcoming PAS 2050, is ideally suited to the retail market but is too simplistic to account for all the environmental burdens that agricultural production entails. This paper introduces a hybrid method, the environmental footprint, which incorporates four environmental indicators (pesticides, greenhouse gas emissions, eutrophication and acidification, and water use) and presents the result as a single figure on a per hectare basis

Finance for on-farm investments in dairy production in Kenya

About 2 million rural households in Kenya produce milk. With about 1800 liters per cow and year, average annual milk production per cow on smallholder dairy farms is low. As a result, production costs per kilogram of milk are high, and profit margins for many farmers are slim. Low cow productivity is also associated with high greenhouse gas (GHG) emission intensity. In 2010, Kenya’s livestock emitted about 16.6 million tonnes of carbon dioxide equivalents (CO2e), of which about 20% was from dairy cattle

Assessment of the life cycle-based environmental impacts of New Zealand electricity : a thesis presented in partial fulfilment of the requirements for the degree of Master in Environmental Management at Massey University, Palmerston North, New Zealand

The life cycle-based environmental impacts of New Zealand electricity arise from the different energy generation systems used to provide electricity to the national grid, and construction, maintenance and operation of the national electricity transmission and distribution system. Due to the high share of hydropower in the New Zealand electricity mix, base load electricity is rainfall dependent and its variable supply is balanced by generation from fossil fuelled power plants, geothermal, and to a lesser extent from wind, biogas and biomass power. This temporal variability of energy sources in the mix changes the Life Cycle Assessment (LCA) results for New Zealand electricity when the environmental impacts are assessed over different time periods. Therefore, this research had two main objectives: to conduct an LCA of electricity generation, and to assess the influence of temporal variation in the electricity mix on LCA results. Using the ecoinvent v 3.1 database and New Zealand-specific data, an LCA model of electricity generation and use was developed for the year 2013. The LCA results, using the CML 2001 – Apr. 2013 impact assessment method, showed that coal and natural gas power plants contributed 10 to 90 % in all impact categories. Electricity transmission and distribution (T&D) infrastructure contributed more than 50 % of the result for Abiotic Depletion Potential (ADP), Terrestrial Ecotoxicity Potential (TETP) and Human Toxicity Potential (HTP) impact categories. The Climate Change Potential (CCP) for 1 kWh of low-voltage electricity was 186 g CO2-eq; for high and medium-voltage electricity, the CCP results were 172 and 176 g CO2-eq per kWh respectively. To investigate the variability in LCA results over different time periods 3, 5 and 10 year moving averages (MAVG) were calculated; as expected, the variability decreased as the time period increased. The analysis showed that the 10 MAVG was associated with the lowest variability in LCA results. However a 10 MAVG will not reflect changes in installed power plant capacity. Therefore for attributional LCA studies of products using electricity over a year-to-year time frame, a representative average of the electricity mix or a 3, 5, or 10 year MAVG can be used as long as there are no changes in installed power plant capacity. This information aids New Zealand´s electricity industries understand environmental impacts associated with transitions to renewable energy technologies and meet greenhouse gas reduction targets

Constructing a greenhouse gas emissions inventory using energy balances: the case of South Africa for 1998

This paper discusses the procedures and results of constructing a greenhouse gas (GHG) emissions inventory for South Africa, using the official national energy balance for 1998. In doing so, the paper offers a snapshot of the South African energy supply and demand profile and encompassing greenhouse gas emissions profiles, disaggregated into 40 economic sectors, for the reference year. For convenience, energy supply and use are reported in both native units and terra joule (TJ), while emissions are expressed in carbon dioxide equivalents and reported in giga-gram (Gg). While carbon dioxide makes an overwhelming contribution to global anthropogenic GHG emissions, the inclusion of methane and nitrous oxide offers considerable richness to the analysis of climate change policies. Applying the energy balances, it was possible to compile a comprehensive emissions inventory using a consistent methodology across all sectors of the economy. The inventory allows the economic analyst to model various economic policies either with fuel as an input to production, or the consumption of fuel or the emissions generated during combustion, as a base of the analysis. The dominant role of coal as a source of energy, with a total primary energy supply (TPES) of 3.3 million TJ or 70 per cent of the total TPES, is clearly shown. Emissions from coal combustion (263 783 Gg of carbon dioxide equivalents or 74.7 per cent of total emissions) are henceforth the largest contributor to total emissions, estimated to be 352 932 Gg carbon dioxide equivalents

Carbon and Energy Life-Cycle Assessment for Five Agricultural Anaerobic Digesters in Massachusetts on Small Dairy Farms

anaerobic digestion, co-digestion, dairy operations, food processing, greenhouse gas emissions, net energy gain, Farm Management, Livestock Production/Industries,