"Efficiency Plus" - resource efficiency, climate protection and production site viability at Viessmann head office in Allendorf (Eder)

Strategic "Efficiency Plus" sustainability project

With its strategic sustainability project "Efficiency Plus", Viessmann has shown that the energy and climate policy targets set for 2050 can already be achieved today. Through the use of commercially available technology, energy efficiency in particular has been significantly increased, as well as operational and material efficiency. Consumption of fossil fuels fell by two thirds, while CO2 emissions were reduced by 80 percent.

All relevant fuel types are utilised in the new energy centre - oil and gas as well as biomass, solar energy and heat sourced from the air and ground. Efficient technologies, such as condensing and CHP, make a vital contribution.

Woodchips produced from the company's own short rotation coppices are used to generate heat and power in an environmentally responsible way. Poplar and willow trees are grown on an area of 180 hectares, covering around half of the annual demand (7000 tonnes) of solid biomass.


Viessmann grows poplar and willow trees in short rotation coppices to obtain biomass.

Biofuel already covers 77 percent of the heat demand at the Allendorf site. The long-term aim is a 100 percent supply using this environmentally responsible fuel. Sustainability is the buzz word here, meaning we use only as much biomass as regrows within the same period.

In addition, a biogas plant employing dry fermentation supplies around 2.7 MWh of power and heat every year. The substrate comprises local agricultural and landscape waste, as well as regenerative raw materials. A second biogas plant was completed in 2013. This is a wet fermentation plant, which uses 15,000 tonnes of substrate annually to generate around 1.6 million cubic meters of biogas. This is upgraded to natural gas quality and injected into the natural gas grid.


The second biogas plant at the Allendorf (Eder) site works employs wet fermentation. The biogas is upgraded to natural gas quality and injected into the natural gas grid.

With "Efficiency Plus", Viessmann has proven that protecting the environment and efficiency in handling resources are not in conflict with economic success and social responsibility. The project serves as an example of best practice. The aim is to motivate other companies, as well as decision makers in politics and administration, to also take or actively promote measures to increase resource efficiency.