Flat ground collector

Bury pipes of the diameter 25-40 mm at the depth of approximately 1.5-2m laid in coils filled with non-freezing liquid.

The length and diameter of pipes, the number of loops, and the depth of laying are selected carefully based on the calculations of heating and cooling power of a heat pump.

The efficiency of this type of lower source is very high.

A contractor that carries out this work has to be familiar with the structure and quality of soil, as every soil type has its characteristic capacity to return heat.

It is assumed that out of 1 running meter of 32-40mm pipes one can obtain from 10W to 20W heating power.

Geothermal drill

From one to even several hundred drills are made in order to recover heat from ground depending on the heating power of a heat pump. The depth of a drill is from 30m to 300m.

A special advantage of this system is that its production does not require a large area of land, but only a few square meters of a plot.

Two pipes are inserted into every drilled hole. They are combined in the lower part with a so-called head.

Pipes from 25mm to 50mm are applied and anti-freeze liquid are used for heat transfer.

Power generated from this type of lower source are from 10W to 35W per one meter of pipe.

The correctly calculated geothermal drills are characterised by the high stability of operation.

Wells

By using water available in ground, which in Poland maintains the all-year temperature from +7°C to +12°C, one can obtain the highest COP level for heat pumps.

This system of energy generation requires the construction of 2 water wells. The first (intake) well is used to collect water and the other (discharge) for returning groundwater cooled by the heat pump. The distance between the two wells cannot be shorter than 20m.

The above-mentioned method of recovering heat from groundwater requires the tests of the mineral and chemical composition of water to be carried out.

High iron or sediment content requires the application of filters or intermediate exchangers in order to prevent damage to a heat pump.

Water reservoirs and rivers

This is the simplest method of heat recovery. Pipes with non-freezing liquid are submerged in a lake, pond or river, and they recover heat stored in water.

Even during the winter season, when the surface of a water tank freezes, the temperature at the bottom is usually about +4°C.

This is high temperature that can be used easily and cheaply to supply heat pumps.

Ventilation air

In large commercial facilities, warehouses and industrial halls, where due to the special sanitary conditions the high exchange of air is required, heat pumps can be used that take advantage of so-called ventilation air to supply the evaporator cooler.

The temperature of air exhausted from the ventilation system and used in heat pumps is often even at 20°C.

Owing to such high temperatures, very high efficiency and COP are obtained comparable even to water-water systems.

Example:
exhaust air temperature from a building at +20°C and temperature of supply water at +45°C. COP will amount to 5.30.
On the one hand, a heat pump collects heat from the ventilation system and on the other hand it heats water and with such heating (or with heaters) it supports the central heating system of the facility.
Heat comes back to the building, transformed into heating power.
The savings of costs generated from such systems are very high.
In case of large facilities, the reduction of heating costs may achieve even 80%.
Owing to this solution, you do not lose heat and energy produced by conventional heating systems.