Hofmann & Vratny

In the category ‘From clever to digital: the broad spectrum of energy efficiency’, the award goes to the Bavarian tools manufacturer Hofmann & Vratny for fossil-free heating and cooling of buildings and production facilities. The measures introduced at their site in Aßling achieved energy savings of six per cent.

Hofmann & Vratny

As part of an energy advice project, this company developed a concept that combines energy-efficient and environmentally friendly methods of heating and cooling, so that the company can manage without heating boilers and fossil fuels. To achieve this, integrated insulation was installed throughout its buildings, and the company’s four production sites were connected by a heat distribution systems to enable heating and cooling to be transferred. At the same time, the company converted the heating system to low temperature. This enabled them to make use of waste heat as well. A constant ambient temperature of 25°C is required for the tools to be manufactured with precision. The ventilation required is achieved by energy-efficient means using cross-flow heat exchangers. On very hot days in summer, the cooling system is supported by a surface ground collector. During the heating period, all office-, recreation- and sanitary facilities are heated using the waste heat from the air compressor and the absorption refrigeration machine used for cooling. Surplus heat is stored in a buffer tank and used at night or in times of increased need. When temperatures are low, cooling for all working areas is provided in a particularly energy-efficient way by using the ‘free cooling’ principle.  Any surplus cool energy obtained is stored in a cold reservoir.

A control system, which coordinates the operating modes of all the energy storage systems with consumers, was installed to optimise energy utilisation.