24 Mar 2021

Vital Energi’s range of vTherm Heat Interface Units (HIU’s) have distinguished themselves as the most efficient HIU’s currently on the market in UK when tested independently against the 2018 BESA Test regime, making them ideal for 4th generation district heating projects that use heat pumps.

Ian Spencer, Associate Design Director for Vital Energi Utilities Ltd. explains, “Heat pumps operate at lower temperatures than traditional heating systems, for heat pumps the lower the temperature the higher the efficiency. Some HIU’s can perform poorly when connected to a heat pump as they are not designed to operate at lower temperatures, resulting in higher flow rates and narrower temperature differentials. This brings down the overall efficiency of a scheme and also generates higher carbon emissions and costs residents more money. Whilst losses may be relatively small on an individual HIU basis, across an entire development these issues can cost thousands of pounds in inefficiencies each year.”

“Our vTherm range of HIU’s was developed with the next generation of district heat networks in mind and the inclusion of heat pump technologies. We believe that the upcoming BESA HIU tests with lower temperatures will clearly demonstrate that the vTherm HIU range is the right choice for 4th generation district heating and renewable energy sourced projects.”

The vTherm range of HIU’s also recorded the lowest VWART (Volume Weighted Average Return Temperature) results when independently tested against the BESA criteria at 60 degrees. This, alongside its low heat losses showed our HIU’s to be the most efficient on the UK market.

Alex Hill, Managing Director of Whitecode Design Associates commented, “After years of Whitecode and Vital working on challenging and interesting projects together it was only natural that Vital would turn to Whitecode to help them understand the value of their new HIU and the systems Whitecode regularly design. It was clear to Whitecode that the Vital Energi product is going to lead the market with ultra-low returns and will be perfect for the upcoming switch to the large-scale application of heat pumps.”

We are currently installing our vTherm units on the Queens Quay Project in Scotland which is the first large-scale water source heat pump project in the UK.
Ian Spencer concludes, “HIU’s are a specialist area and it’s important developers are in contact with experts at every stage as not all units are suitable for modern projects. This is such a critical area, and has such a strong impact on overall efficiency, that getting it right is essential for a successful 21st Century energy project.”

For more information on vTherm, please visit: https://www.vitalenergi.co.uk/hius-overview/



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