Developing KPIs for the Energy-flexible Operation in Energy Systems in the Dairy Industry

In the Paris Climate Agreement 2015, 195 countries committed to reducing their greenhouse gas emissions to counteract climate change. In Germany, the dairy industry has significantly contributed to reducing greenhouse gas emissions in recent years. The milk production still accounts for 3 % of total greenhouse gas emissions worldwide, of which the dairy level accounts for 17 %. Energy consumption per ton of milk has fallen by 15 % to 20 % since 1990, thanks to improved energy efficiency and renewable energy technologies. Energy costs still account for around 1.5 % of the annual turnover of dairies. In order to face the economic and ecological challenges, energy flexibility measures (EFMs) can be implemented. In addition to the cost reduction possibilities, implementing EFMs also contributes to reducing CO<inf>2</inf> emissions. This paper proposes an energy flexibility assessment approach based on using EFMs according to key performance indicators. The VDI guideline 5207 provides the framework for the examining EFMs and their prioritisation in consideration of the specific requirements of the dairy industry. The presented procedure, identifies objectives of an energy flexible energy system, prioritises them, and selects suitable EFMs inherent to the energy system of the dairy industry to act upon the identified objectives. Key performance indicators are derived from the objectives and prioritised to quantify objective fulfilment. The proposed method enables the use and evaluation of energy flexibility in industrial energy systems and demonstrates this for the dairy industry.