Using Heat Pumps to Supply Thermal Energy
Detailed description of the Good Practice
Heat pumps systems have been installed at Komorowice Wastewater Treatment Plant and
Aqua Centre of Recreation (swimming pool & fitness).
Heat pumps at the Komorowice WWTP were installed in 2005. The system installed consists
of three pumps of 14kW each. The system is connected to an electric boiler of a capacity of
24kW which supplies energy in times of peak demand. At Komorowice WWTP, waste water is
used as the bottom heat source, characterized by a minimum temperature (winter)
above 6 to 8°C. The water flows through the sand trap system, with eight coils made of
polyethylene pipes of the diameter of 40mm and of the length of 300 running meters each.
The collector system, being the heat sink for the bottom source, is filled with a blend of glycol
and water in a proportion of 1:3. The heat pumps produce a top source of heat of 45°C to
55°C. Heating fluid circulates within a closed system and supplies radiators, convectors, as
well as heaters.
The installation has been executed in a way enabling for separate and independent feeding of:
- Administration / office building for the treatment plant personnel,
- Administration / workshop building for the maintenance department personnel,
- Screens grids’ building.
In total a volume of over 6,000m3 room space, all sanitary water for about 80 employees as
well as four digestion chambers of a total capacity of 8,000m3 are heated.
The use of waste water within the heat pump system as a source of energy is in the case of a
WWTP the best possible solution. Recovering of energy from waste water, of which
temperature throughout the year does not drop below 6°C, allows for a better heat recovery
compared to the use of flowing surface water or ground heat.
Heat pumps of a capacity of 350 kW were also installed in the City's new indoor swimming
pool and Aqua Fitness Club (opened in 2006). The pumps use the heat contained in piped
water supplied to the residents of Bielsko-Biała and the heat from swimming pool ventilation in
order to heat and air condition the building in the summer season. The system is backed up by
a gas-fired boiler during periods of maximum energy need.
renewable sources of energy
Objectives of the Good Practice
To reduce both overall cost and negative environmental impacts due to heating activity.
Participants of the Good Practice
the City of Bielsko-Biała
More Details of the Good Practice
Heat Pumps at Komorowice Water Treatment Plant
- Bottom heat source: untreated wastewater (min. temperature: 6°C)
- Temperature achieved at the top heat source – 45°C to 55°C
- Application: room heating of 6,000m3, sanitary water heating(storage tank of 700l),
heating of four digestion chambers (of 8,000m3)
- Working efficiency: 4.44
- Benefits – 600 kWh of electric power instead of 250 m³ of gas per day
- Payback period of installation instead of traditional gas installation equals 5 years
Heat pump at Aqua Recreation Centre
- Bottom heat source: drinking water supplying the City
- Heat recovery from ventilation system
- Application: heating of water in indoor swimming pool (max 31.5°C), heating and airconditioning
of swimming pool and fitness centre space (total volume of 15,000 m³)
- Payback period: about 2 years
Marcin FILIP, Asistent Deputy Major, City of Bielsko-Biała
Tel: / E-mail: firstname.lastname@example.org, Website: www.um.bielsko.pl/bb/
Data sources and references
Association of European local authorities promoting local sustainable energy policies
(Accessed December 31, 2009)