Free heating, temperature conditioning at half price - Reisner AG

into fuel oil saved. The system has a calorific value of 9 kWh per liter. The estimated waste
heat stream of 197 kW is therefore equivalent to 21.9 liters of fuel oil per hour. If a liter of fuel
oil costs 0.60 EUR, then heating the hall with waste heat saves more than 13 EUR for each
hour of operation as compared with oil heating. Therefore, the amortization period for the
additional investment for the heat recovery is certain to be short, especially in view of the
prospect of continuing increases in oil prices.
Temperature conditioning units on injection molding machines can often be operated by
means of waste heat. However, this application generally requires an especially high heating
medium temperature of at least 60°C. Such temperatures cannot always be achieved simply
by the use of the existing waste heat. A higher condensation temperature is necessary; the
compressor uses more electric energy and the energy efficiency rating of the system drops.
Nevertheless, the use of waste heat can also be very worthwhile in this case. If, for example,
water with a temperature of 60°C is to be provided by the 155 kW cooling unit from our
example above, the output of the system drops to 123 kW. At the same time, the energy
consumption increases to about 67 kW. This results in a total thermal output of 190 kW
which is available for the temperature conditioning units. Operated with electricity, the ratio of
expended energy to generated energy would be 1:1; therefore, the operating costs would be
nearly cut in half in this example.
Severe winters, zero
heating costs. It can be
done – with the Reisner
system, which converts
Despite all the possibilities resulting from the new heat recovery concepts, Reisner never
loses sight of the fact that the core function of their systems is cooling. The main goal here is
always to achieve outstanding energy efficiency ratings. After all, the cooling system is
needed for production anyway and has to be integrated in the production process to the
fullest extent possible. That also has to be considered in amortization calculations, which
should estimate only the additional expense for the waste heat utilization.
Reisner AG ·Free heating, temperature conditioning at half price· 4