Give and take

In case of a not useable heat overflow in the house, the heat is given to the underground.

This action to transfert heat from the house in the cooler underground will in this chapter be called a "download" or thermical load cycle.

This head can at demand taken again from the underground with a heat pump. This action is called in this chapter an "upload" or thermical discharge cycle.

This heat exchange with the underground is not at all to understand as a low temperature saisonal storage. A computer simulation with actual data from November and December 1991 shows this clearly.

There are also downloads in winter! Each time in the first half of November and December had been sunny days with much overflow heat. The data are from the Austrian association "Energiewerkstatt". By order of an Austrian ministry had been build near Strasswalchen a measuring system for global solar adiation, diffuse and direct, wind, air humidity and temperature. The data had been logged every 10 minutes.

So there are in a year more than one thermical load and discharge cycle with the underground. The results are special to recognice, because the solar radiation was in November far below average and the first half of December the coldest since decades.