CTC cuts heating costs for workshops with heat pumps and free cooling

CTC cuts heating costs for workshops with heat pumps and free cooling


Welcome to Valdemarsvik. The area is home to the beautiful skerries of Gryt and Tjust, as well as Allvärmeteknik, one of CTC’s major partners. With Östergötland's largest energy and bathroom store, they are hard to miss when you arrive by car and approach Valdemarsvik.

Each year, Allvärmeteknik installs around 200 heat pumps from CTC. One of Allvärmeteknik’s corporate customers is Bilam. 

1,200 metre borehole for 1,200 square metres. 

Bilam in Valdemarsvik is a full-service vehicle facility. The facility comprises a workshop, store, spare parts department, car washing, petrol station, and car and trailer rentals with 11 employees. 

- A year and a half ago, we invested substantially in our new facility. A state of the art workshop spanning almost 500 square metres together with offices, a store and changing rooms. 1,200 square metres in total, says Workshop Supervisor Peter Törnborg. 

An important part of the investment calculation. 

The heating and hot water solution constituted an important part of the investment calculation. Large areas, high ceilings, entranceways and a combination of offices, workshops and changing rooms with significant hot water needs over short periods required a well-planned solution.

- The foundation of the entire facility is ground source heating. District heating is available, but it was quickly rejected. At the time of planning, CTC EcoZenith had just been launched. It provided a perfect all-in-one solution for control and hot water, says Jonny Carlsson, Service Manager at Allvärmeteknik. 

Ground source heating and free cooling. 

With the help of four fan convectors, free cooling is a technical solution that has worked superbly. 

- Free cooling is a clever way to utilise the free energy available in ground source heating. A huge advantage of free cooling connected to a ground source heat pump is that the borehole is recharged with energy. When the heat pump needs to produce hot water, the temperature of the incoming brine is a few degrees warmer than it would otherwise be, says Johnny Carlsson. 

A rule of thumb is that a borehole providing 5 kW of heat output can be loaded with around 3.3 kW of cooling. For each degree the brine temperature is increased, the efficiency of the heat pump increases by approximately 3 %. 

Baptism by fire: Worst winter in living memory. 

The system had to prove its worth in the winter of 2010/2011, which was the coldest winter in Sweden since records began being kept. 

- We were surprised at how little additional heating had been connected since start-up. Just over 7,000 kWh in total in a year and a half. It seems like good confirmation that the system really is performing at its peak, says Johnny Carlsson. 

Return visits by Allvärmeteknik have been few and far between. The heating system has functioned like clockwork. 

- Since the start we have only had two error alerts, both of which were power outages. Otherwise the system has functioned like clockwork with an even and correct temperature. Hot water capacity in CTC EcoZenith has really lived up to our expectations. For instance, when we had a sauna evening with 12 people who all showered, we experienced no problems with the hot water, concludes Peter Törnborg.