National University of Ireland, Galway1
The dairy ingredients and products industry is Ireland's largest indigenous industry and comprises a vital part of the agri-food sector. Additionally, dairy ingredients and products contributes to almost 30% of the Irish food and drink export market and, in 2013, dairy ingredients and products surpassed 3 billion euro for the first time (National Milk Agency, 2014). However, the Irish industry is about to embark on a period of significant change with the abolition of milk quotas in 2015, where a 50% increase in milk production by 2020 is expected. As a result of this increase, resource usage will become an even greater concern than ever before. Therefore, efficient and effective management of resources will greatly influence the growth and competitiveness of this industry.
Water and energy are two of the main resources which affect the environmental impact of the Irish dairy processing industry. Efficient use of direct energy will need to be improved to reduce costs and reduce the carbon footprint of the industry. One method of estimating the carbon footprint, or global warming potential, of an industry is to perform an environmental life cycle assessment (LCA) which takes account of the greenhouse gas (GHG) emissions associated with the resources and processes which comprise that industry. However, in order to perform this assessment, a lifecycle inventory (LCI) must be compiled and the information provided and discussed in this paper will comprise a portion of the LCI for the Irish dairy processing industry. In addition to the effect it will have on the global warming potential of the industry, water consumption will need to be reduced and more effective solutions for the treatment of dairy wastewater will need to be found if the plants are to abide by the stringent measures on emissions to water bodies being imposed by the Environmental Protection Agency (EPA). This will also help with the reduction of costs incurred by plants and, in turn, contribute to improving the competitiveness and growth of the Irish dairy processing industry.
In this paper, the water consumption and direct energy use associated with the Irish dairy processing industry are assessed. In order to provide an accurate assessment of the industry, data was used from 18 dairy processing plants located in the Republic of Ireland. These plants processed an average of 5230 million litres of raw milk per year between 2009 and 2013, which accounts for approximately 93.5% of the total raw milk processed in the Republic of Ireland during this period. The total water consumption, along with its source: groundwater; surface water; public supply, is assessed. Direct energy use is split up into electrical energy, which is comprised of electricity from the Irish grid and on-site generated electricity from combined heat and power (CHP) systems, and thermal energy, which is derived mainly from natural gas, coal and fuel oil.
Overall annual water and energy usage statistics for the 18 dairy processing plants are presented for the period between 2009 and 2013. Additionally, statistics for water consumption and direct energy use are presented at plant level, which is summarised using boxplots, and an overall industry mean. The results of this analysis are compared to the results of a similar study performed by Dr. Robert Geraghty of Enterprise Ireland (Geraghty, 2011). A case study of a 'typical' Irish milk powder and butter plant is used to illustrate how water and energy are used within the plant. The results from surveys of a number of Irish dairy processing plants are used to generate the data used within this study. From this case study, the main water/energy users within a plant can be identified and the potential water/energy savings are discussed.
As the use of water and energy is the main topic of discussion in this paper, it is fitting to discuss the energy water food security nexus with respect to the Irish dairy processing industry. Not only is the direct water consumption affecting 'freshwater depletion' but also the embodied water associated with the other resources inputted into the dairy processing plant. Since this paper deals with energy and water, the water footprint associated with these two resources is calculated in order to estimate its significance compared to direct water consumption. This analysis will be performed using the case study of a 'typical' Irish milk powder and butter plant. Geraghty, R. (2011) Resource efficiency in Ireland's dairy processing sector. Enterprise Ireland. National Milk Agency. (2014) Annual Report and Accounts 2013.