Commercial Bakery – ENERMAX System with ROSC20 Solar Control & Gas Boost


Commercial bakery in Sydney, NSW. Large scale manufacturing operation, with consistent high volume water heating needs for manufacturing, systems cleaning and office hot water supply.

System Requirements:

Due to manufacturing expansion, additional hot water supply was required.

Hot water requirement of 4,600L in the first hour with 4,000L/hour recovery, all delivered at 65°C.

There was concern the existing system would not be capable of meeting this increased demand, and as energy costs were higher than desired an additional objective was to minimise grid-supplied AC electricity through off-grid solar PV as the primary energy source, with gas boost backup when required to additionally service the water heating load.

Original System:

  • Traditional design plant –
    2 x 315L Heavy Duty Triple Element Electric Steel Cylinder Storage tanks

ENERMAX ROSC20 System Installed:

  • 2 x ENERMAX SMARTcube SC500 tanks, comprising dual 316 stainless steel coils to provide hygienic hot water and high flow rate capability

  • 2 x ESW ROSC20 direct solar PV powered elements providing 2kW of solar yield into each ENERMAX SMARTcube
  • 3 x Noritz 50L/min condensing Commercial Continuous Flow gas, 330MJ/Hr at 95% thermal efficiency
  • 16 x 275W Solar PV panels, set onto 45° angled tilt frames

System Performance:

  • Footprint – No increase in plantroom footprint, with Solar PV panels located separately on the building roof.
  • Performance – is consistently delivering 4,600L at 65°C in first hour with an hourly recovery of 4,000L at 65°C as required.
  • Efficiency

    • Angled mounting of Solar PV panels is consistently delivering above average solar gain, even through Winter months.
    • High constant tank water temperature maintained across both tanks:
      • Maximum temperature average of 73°C/72°C (Tank 1/Tank 2), peaking at 76°C
      • Minimum temperature average of 60°C/61°C (Tank 1/Tank 2) and not dropping below 57°C.
    • NIL grid-supplied AC electricity required in 204 days since installation, including Winter. Backup boosting, if required, provided by the condensing Commercial Continuous Flow units.
    • The ENERMAX SMARTcube tanks act as energy batteries when energy is not being demanded, banking energy for future use.
    • Lower electrical energy demands vs the previous triple element dual tank system


The new Thermal Energy Solutions system meets the client’s requirements for reliable high-volume Commercial water heating with improved energy efficiency. Relying primarily on solar PV energy input, it meets the client’s targets for performance and efficiency and will continue to do so over its life due to the unique system design.