Acting sustainably also and most particularly involves the responsible use of available resources. For us as a company with energy-intensive manufacturing processes, the use of energy as a resource is of great importance from both an economic and environmental viewpoint. With the implementation of targeted energy efficiency measures, there is also a possibility to further optimize the energy consumption of the SÜDPACK Group.
The significance of energy efficiency led to the implementation of an energy management system in accordance with ISO 50001 in 2011 at our most energy-intensive site in Ochsenhausen. Certification has been carried out regularly since then.
In the last three years, the total energy consumption of all surveyed energy sources has increased in absolute terms. This is mainly due to the expansion of our capacities in the areas of extrusion, laminating and regranulation.
Electrical energy is by far the main energy source of the surveyed sites. In addition, we use the energy sources gas, heating oil, diesel and coal. Hot gas from RTO lines (regenerative thermal oxidation of solvents) is also used. It is used to heat the drying channels and produce steam at the Ochsenhausen site and in Kłobuck for the thermal oil heater of the drying channels in the production facilities.
The energy efficiency of our lines in relation to throughput in tons (energy kWh/through-put t) declined during the 2019 reporting year compared to the previous year. This because we have systematically continued to reduce the thickness of our films in recent years. Assessing energy efficiency in relation to throughput in m2 (energy KWh/through-put m2) makes improvement visible.
Energy efficiency by area (kWh/1,000m²)
In addition to the implementation of energy efficiency measures, we are also putting additional extensive measures into practice to optimize our energy supply. Thanks to the self-generated energy from our cogeneration plant (CHP), which began operation in late 2016, it was possible to reduce the external purchase of energy to supply our site in Ochsenhausen by 35 %. The waste heat that is generated is fed into Ochsenhausen's local heating network or used to produce steam. The steam is used in the drying channels of our laminating operations.
To produce compressed air, we invested in a new compressed air system with heat recovery. Furthermore, a photovoltaic system was installed at the Ochsenhausen site in late 2019. In the future as well, the aim is to further increase the share of self-generated renewable energy with additional investments. Moreover, measures are planned to renovate and insulate buildings as are cooling systems for our extrusion lines.
At our site in Bioggio, extensive roof renovation work was completed, which has resulted in improved energy efficiency. Similarly, investments were made in 2018 in an energy-saving lighting concept, which accounts for an annual savings of roughly 67,000 kWh. In 2019, we also installed a heat recovery unit for our activated carbon desorption process for solvent recovery. With this investment, the annual savings amount to 790,000 kWh.
At our site in Kłobuck, we are going to replace coal utilization by transitioning to natural gas. Kłobuck is currently the only site where coal is used as an energy source.