‘AquaEfficiency’ an energy-efficient solution for tap water heating

REHVA Journal – October 2012

Stefan LM Eriksson

Alfa Laval, manager Heating & Cooling Systems

stefanlm.eriksson@alfalaval.com

AquaEfficiency – Alfa Laval’s latest innovation in the area of tapwater heating for collective applications – is the most energy-efficient solution available in the market. Compared with other offerings in the market, an AquaEfficiency system can save energy up to EUR 2,200 annually which means that the pay-back period of the extra cost for an AquaEfficiency is less than one year.

Avoiding off-peak waste

AquaEfficiency is based on Alfa Laval’s well-proven ‘AquaFlow ‘and ‘AquaStore’ tapwater heaters. These systems have been equipped with new variable-speed pumps and a new, advanced system controller. The controller reacts on variations in the outgoing water temperature (within 1-2˚C) and adjusts the pump speed accordingly. At every moment, the controller selects the optimum combination of pump speed and valve aperture to achieve the most effective adjustment.

AquaEfficiency

Recovering condensation heat

Condensing boilers are rapidly becoming the norm for space and tapwater heating in Europe. However, with return temperatures from the heat exchangers typically in the 45-55˚C range, the condensing potential is largely wasted. AquaEfficiency, therefore, uses a second sensor to monitor the return temperature and maintain it at 35˚C or lower during tapping periods, which is ideal for condensing boiler heat. By recovering this heat, valuable energy can be saved.

Working principle of AquaEfficiency.

Alfa Laval has patented this dual-sensor approach to simultaneously controlling pump speed and return temperature. AquaEfficiency really seems to be the right product introduced at the right time.

More information: www.alfalaval.fr