Roth water-to-water heat pumps with external heat exchanger

Interaction of nature and technology

Groundwater as an energy source - favorable possibility of regenerative energy production

Water is a medium with a very high storage capacity, a very balanced temperature level and a very good regeneration. Three strong reasons to include this element as a natural heat source in the energy supply.

Groundwater is the most effective heat source for a heat pump compared to air and soil. An important prerequisite is that groundwater is available in sufficient quantity and quality. Since groundwater has high and constant temperatures of 8 °C to 12 °C all year round, the heat pump starts its heat refinement from a higher temperature level than when using brine or air.

Roth water-to-water heat pumps

Based on water temperatures that remain constant almost all year round, Roth ThermoTerra heat pumps combined with a high-quality external heat exchanger for system separation enable the best performance figures and thus favorable operating costs for the user.

Roth ThermoTerra brine/water heat pumps are used. In order for these to be operated as water/water heat pumps, an external plate heat exchanger is required for system separation of the brine side and the water side. Roth also offers these high-quality stainless steel heat exchangers as options in its product range.

 

Products

Roth brine/water heat pumps

Water is life,
life is energy,
energy is water

This cycle is supported by the ThermoTerra water-to-water heat pump.
Groundwater is used as an energy source via a well system consisting of production and absorption wells. This variant of heat pump technology is a very inexpensive way of generating renewable energy for heating and supplying hot water to buildings.

A submersible pump is used to extract the groundwater from the production well and transport it to the heat exchanger of the heat pump. Energy is extracted from the water there. Depending on the design, it cools down by up to four Kelvin, but its composition is not changed. The water is then returned to the same groundwater vein via an absorption well located about 10 to 15 meters away.

Deep boreholes are very expensive, so for one- and two-family houses the usable groundwater should be at a maximum depth of 15 meters.

Notes

The following points must be observed during system planning and execution:

  • The use of groundwater as an energy source must be approved by the water authority.
  • Depending on the heating capacity, a minimum volume of water is required, which must be provided by the well system as a continuous output.
  • The water temperature must be at least +7 °C all year round.
  • In general, a water analysis by a water technical laboratory is recommended. Initial information about possible groundwater use can be obtained from the local water supply companies.
  • By means of a pump test, information is obtained about the available water quantity as well as the quality and temperature of the water.
  • The well installation must comply with the existing legal regulations, ordinances, standards and guidelines and be constructed by an approved drilling company (DVGW W 120).