Sydthy Spa and Swimming Pool

Wellness and unique experiences are given top priority at the public pool centre Sydthy Spa and Swimming Pool regardless of whether you are a guest at the spa, which is reserved for adults, or whether you are visiting the swimming pool which is for everybody.

Sydthy Kur- og Svømmebad
Idrætsvej 5, 7760 Hurup Thy
Phone: +45 99 17 31 60

  • Guided tours: By appointment
  • Open for guided tours: By appointment
  • Booking: Please contact Sydthy Spa and Swimming Pool
  • Participants: By appointment
  • Admittance fee for guided tours: By appointment
  • Parking: Parking ground by Sydthy Spa and Swimming Pool
  • Public transportation: Sydthy Spa and Swimming Pool is located close to the train station in Hurup
  • Toilet: Yes
  • Language: Danish.



IMG_7841 is all about pure relaxation in beautiful and serene surroundings while the swimming pool is complete with water slide, children’s pool, warm water pool and a Roman bath.
Sydthy Spa and Swimming Pool is awarded with the Green Key – an international eco label for the tourism and leisure branch allowing consumers to choose businesses that are ecologically sound and responsible. Green Key businesses focus on reducing resource and energy consumption and on using environmentally friendly products. To maintain the Green Key award constant improvements are required which is why the environment is always a concern at Sydthy Spa and Swimming Pool.

District Heating

27 The comfortable temperatures in and out of the water in Sydthy Spa and Swimming Pool are due to district heating from the local district heating plant in Hurup. Here the boilers are fired with wood chips from Thy National Park and power from the many wind turbines in the area. These are heating methods with a low carbon footprint according to the Green Key criteria.

Solar Power

The roof of Sydthy Spa and Swimming Pool is fitted with a 20 kW solar power system producing 20.000 kWh per year which covers some of the centre’s power consumption but not all. Apart from lighting the main power consumers are the ventilation system and the water recycling pumps – and this is where there is money to be saved through energy optimization.

Ventilation and Heat Recovery

With a relative air humidity between 48 and 55 inside the swimming pool a well functioning air conditioning system is of paramount importance to both indoor climate and the preservation of the building. Condensation on walls and ceilings will result in stains requiring extra maintenance and as a result the ventilation system runs as needed. The ventilation system in the basement below the swimming pool controls the temperature and air humidity in all areas of the centre treating 42.000 m3 air per hour. 8 minor systems all operate by heat recovery through a heat exchanger recovering heat from the air in the swimming pool. This energy efficient way of heating the centre also secures a comfortable indoor climate in every room. Optimizing the energy consumption also means frequency controlled ventilation ensuring an even flow adjustable according to the number of guests in the facility.

Recirculation and Water Quality

sydthy-kurbad_20131008-DSC_4016 Maintaining a high water quality is vital for Sydthy Spa and Swimming Pool making water consumption reduction a challenge. Prolonged water recirculation time results in particles in the water that are too small for the filters to retain. This leads to bacteria growth which requires extra chlorification and reduces the water quality. Samples from Sydthy Spa and Swimming Pool have never shown significant bacterial counts. This is mainly due to the extensive cleaning process of the entire water circuit which takes place in the 400m2 large engineering room in the basement. Recirculation speed depends on how many guests are using the facilities. The water in the large swimming pool is replaceable within four hours while the water in the hot water pools is replaced within 20-25 minutes. The fully automated Captura® filtration system filters the water through a combination of coal and sand. The water initially trickles through a layer of coal and subsequently through sand. During this process the water undergoes UV radiation which kills bacteria. The method used is slow sand filtration which happens without applied pressure thus saving energy. The system was the first of its kind to be installed in a Danish swimming pool and is performing so well that similar systems eventually will replace the two pressure sand filters and the three coal filters in the basement. Components in the Captura® filtration system are made from very durable materials that will not corrode or weaken with the constant heat they are subject to.

After rinsing the filters 4 – 5000 m3 of backwash water per year is lead into the sewer resulting in quite significant bills at the sewage treatment plant. But a new project is in the pipeline to remedy that fact: The backwash water is led to a separate tank where particulate matter will be allowed to settle before the water is clean enough to be directed to the rainwater well.

The Chemist in the Basement

sydthy-kurbad_20131008-DSC_4042 Water treatment with physical purification of the swimming pool water through filters is important but not sufficient. The water also needs to be disinfected which is done by adding chlorine. Sydthy Spa and Swimming Pool is the first public pool in Denmark to install its own on-site hypochlorite production plant in the basement. The system is a prototype developed in cooperation with Danish Technological Institute and Jysk Svømmebads-Teknik A/S. The chlorine used in Sydthy Spa and Swimming Pool is produced by an electrolysis unit in the engineering room. First of all this production method minimizes the risk of accidents when industrially produced chlorine is transported on the roads from plant to swimming pool. Secondly this method of adding chlorine allows for a smaller dosage of chemicals which helps improve the water quality. Thirdly Sydthy Spa and Swimming Pool can avoid having large quantities of chlorine stored in the basement constituting serious health hazards in the event of a fire or leakage.

The chlorine is produced by electrolysis which is a method for separating matter by electricity. An electrochemical cell passes a direct electric current through a solution of salt in water. The positive ions in the solution are attracted to one of the electrodes in the cell, the anode, forming chlorine. The negative ions in the solution are attracted to the other electrode, the cathode, forming hydrogen. The hydrogen is released since only a small quantity is produced while the chlorine is directed into the swimming pool water in carefully adjusted intervals. A Dulcomarin® measuring and control system regulates the pH value and chlorine content while an Elektrocell® 300 control system has been installed for extra surveillance and security.

The system helps maintain a very high level of disinfection with the use of as few chemicals as possible. Industrially produced chlorine contains approx. 80% preservatives as opposed to the chlorine produced at Sydthy Spa and Swimming Pool which is put to use immediately eliminating the need for added preservatives. Due to the electrolysis system Sydthy Spa and Swimming Pool has obtained a special permit for low chlorine content even in the hot water pools. Furthermore the results from Sydthy Spa and Swimming Pool have contributed to an alteration to the decree for regulating public swimming pools to the effect of allowing the pH set point to be lowered to 6.8 instead of 7.0. The pH value is crucial for the ability of the chlorine to kill bacteria and germs. Maintaining good water quality with as few additives as possible is essential to the user’s experience, particularly if the guest suffers from asthma or has problems with the immune system.


sydthy-kurbad_20131008-DSC_4034 Four frequency controlled Grundfos pumps make for optimal operation and flow through pipes and heat exchangers. The pumps have a ceramic coating on the inside to prevent bacteria from forming over time. The four heat exchangers are cleaned on a regular basis to keep the pipes open securing a proper flow and thus saving energy for pumping.

Production Data

  • Solar power: 20.000 kW per year
  • Water consumption: 7300 m3 per year
  • Guests: 90.000 per year.