A new district heating system in Rørvig, Denmark – which is powered by Danish OEM Advansor’s SteelXL CO2 (R744)-based heat pump – will help reduce residents’ energy bills by up to 50% and CO2 emissions by up to 70%, according to a case study from Casper Christiansen, Business Development Manager for Heat Pumps at Advansor, and Martin Sønderby, Sales Manager at Aktive Energi Anlæg (AEA), the project’s designer and contractor.
The case study was presented by Christiansen and Sønderby during an HVAC and heat pumps session at the ATMOsphere (ATMO) Europe Summit on natural refrigerants. The conference took place November 15–16 in Brussels and was organized by ATMOsphere, publisher of R744.com.
Advansor’s air-to-water heat pump has a heating capacity of 1.5MW (426.5TR) and will provide around 244 households in Rørvig with heat for hot water production and space heating. Previously, most residents used oil burners or electric heating, explained Sønderby.
By transitioning from gas heating to a CO2 heat pump, consumers will save around €2,000 (US$2,050) a year in heating costs, he added.
According to Christiansen, the adoption of the district heating system in Rørvig will save 300,000m3 (10.6 million ft3) of gas each year, which will avoid the emission of 470 metric tons of CO2e annually.
“Not only are there economic benefits in choosing a CO2 heat pump, but it’s also a sustainable and environmentally-friendly solution,” he added.
“Not only are there economic benefits in choosing a CO2 heat pump, but it’s also a sustainable and environmentally-friendly solution.”Casper Christiansen, Advansor
The system, which is still in the commissioning phase, is designed to have a COP of 3.1 at an ambient temperature of 2°C (35.6°F). At a recent inspection, it is currently “on target” having achieved a COP of 3.4 at 11°C (51.8°F), said Christiansen.
To ensure this level of efficiency, the heat pump includes permanent magnet motors on the 12 compressors – six medium temperature and six intermediate – which results in 8% energy savings. It also includes a high-pressure lift ejector that reduces energy consumption by a further 5–10%, he explained.
The heat pump also comes with a standard controller platform to make maintenance and service of the system easier for contractors and other service partners, added Christiansen.
The district heating system includes three Evapco evaporators, which were chosen by AEA based on previous experience with the product and the flexibility for installation and because AEA had participated in its development, explained Sønderby.
District heating in Denmark
With a national goal to reduce CO2 emissions by 70% by 2030, Denmark is leading the way when it comes to district heating in Europe, said Christiansen.
“We have to stop burning things to stay warm, and solutions are here with heat pumps with natural refrigerants, and of course with CO2,” he added.
In support of this goal, district heating companies are obligated to convert as many households as possible to a sustainable heating source, explained Sønderby.
In Rørvig, residents were given the choice between converting to a modern domestic heat pump or joining the district heating system.
In this case, 244 households chose the district heating option, and AEA was selected as the project contractor responsible for suppling the machinery, piping and electrical work, as well as maintenance and servicing for the next 5–10 years, added Sønderby.
In addition to being installed at Rørvig’s district heating plant, an Advansor SteelXL heat pump was also recently installed at a district heating plant in Frederiks, Denmark, following its exhibition at the Chillventa trade show in Germany last month.
Advansor has been producing heat pumps since 2006 and now has a range of systems that can provide up to 10MW (2,843TR) in sustainable and energy-efficient heating and cooling for commercial and industrial applications.
Advansor is hosting a webinar about its heat pumps on December 1.