Gekoppelte Kälte- und Wärme - Huber Energietechnik AG

Gekoppelte Kälte- und Wärmeerzeugung mit Erdwärmesonden Abstract
Abstract
In restaurants, bakeries and a lot of grocery stores, there is very often at the same time a need for heating as
well as cooling. Normally, this problem was solved by using a traditional heating system (with oil or gas
burners) and by one or several cooling devices. Often, the waste heat of the refrigeration was not recovered,
or worse, was even let into the rooms that needed to be cooled down by an air conditioning system.
In such situations the use of a single heat pump system that meets the needs of all cooling and heating demands
should be considered. This system can be used for heating, production of domestic hot water, air
conditioning and cooling of storage rooms at different temperature levels. When different heat pump layouts
are compared, the systems with direct evaporation are preferable to systems with an intermediate, hydraulic
heat distribution. Since standard heat pumps cannot be used for this direct evaporation, the heat pump
supplier should be involved in the planning as early as possible. The described solution is already several
times installed and successfully tested. The planning process (cf. Bild 2.14) is described in detail in this
handbook and with an example explained.
One of the key points of such systems is the simultaneity of heat and cooling demand. Within the period of a
day, heat storage tanks can compensate a certain temporal difference in demands. The demands of a
seasonal fluctuation can be met by a ground coupling of the heat pump system: Vertical boreholes are very
suited to yield the needed heat in the winter and to absorb the waste heat in the summer. The designing of
such a field of vertical boreholes and of the heat storage tank is one of the main issues of this report.
For an energetically comparison of different systems, the energy efficiency ratio for heating and cooling
(GLZ) and the performance efficiency ratio for heating and cooling (GAZ) are introduced. The comparison of
different systems shows, that even with a moderate performance of 2.5 of the heat pump, the combined heat
and cooling generation is more efficient than a solution with separate heating and cooling. In the described
example, the combined solution needs 4.5 times less energy for the heat production than the traditional
solution with an oil heating does.
This handbook is written for engineers, but not especially for heat pump manufacturers. A theoretical part
can be found in chapter 1, the planning proceed as well as examples are located in chapters 2 to 5. A
detailed appendix finishes the handbook.