Energy label “A” for the Roth Thermotank Quadroline heat storage tank – up to 65 per cent less heat loss


Following tests conducted by the Fraunhofer Institute for Solar Energy Systems ISE in Freiburg, the Roth Thermotank Quadroline heat storage tank model equipped with the Roth Thermocoat plus has been awarded energy label A. Under the European Union Ecodesign Directive, from 26 September 2015, heat storage tanks will also be labelled with the familiar energy label. 

The Fraunhofer Institute’s results confirm heat losses S of 59.3 Watts for the 500-litre Roth Thermotank Quadroline with Thermocoat Plus. The test results show that the Roth Thermotank Quadroline heat storage tank exhibits up to 65 per cent less heat loss than standard storage tanks, making it a top performer in energy efficiency.

Jens Haffner, Head of Energy Systems Research and Development at Roth, explains: “During standstill of the storage tank, with no withdrawals, the standard Thermotank Quadroline with its plastic shell and high-quality EPS insulation exhibits over 50 per cent less heat loss than a steel storage tank. The standard version is therefore awarded energy label B. When equipped with the optional Thermocoat plus, the Thermotank Quadroline can even cut heat loss by more than 65 per cent compared to a steel storage tank and it is therefore awarded energy label A.” If the storage tank falls below the set-point temperature, the connected heat generator reheats it. Owing to its lower heat loss, the Roth Thermotank Quadroline can reduce heating processes by a quarter.

The pressure-resistant Roth plastic composite Thermotank consists of a thermally stable thermoplastic tank and high-performance composite filament material with integral diffusion protection. The energy balance of the Thermotank is considerably better than metal storage tank materials thanks to the optimum heat insulation properties of the storage tank material. The combination of the storage tank’s innovative plastic composite material and the special high-performance EPS insulation enables efficient minimisation of heat loss.

The innovative plastic composite thermotanks are available in 325, 500 and 850-litre sizes. The storage tank concept permits hygienically safe, state-of-the-art integration into the domestic heating and water system and allows the use of solar energy. Thanks to their structure, the Roth Thermotank Quadroline models can be used in individual system designs. They are used as central units for heating applications, as separation or buffer storage tanks, as solar and combination storage tanks and for heating domestic water. The Roth Thermotank Quadroline models can be integrated directly into heating systems with a maximum continuous operating pressure of up to three bar. The tank is extremely light, weighing only around a third of the weight of a comparable conventional steel storage tank, which makes for easier transport and installation. A further advantage of the specially certified plastic composite material is that it is corrosion-free.

The special manufacturing process used – composite filament winding technology – makes the Roth heat storage tank pressure-resistant. This technology is used for lightweight products with high requirements in terms of pressure and corrosion resistance. Media such as liquefied gas, natural gas and hydrogen are stored in composite pressure vessels. The pressure applied can reach up to 800 bar. Composite products are used, for example, for water hygiene applications, as gas cylinders and tanks for the automotive industry, and in the aerospace industry. With its firm EHA Composite Machinery, Roth has been a market leader in composite technology since 1964.