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EnergyLink has offered the EnergyLink smart energy management system with submetering to this Sydney pub. EnergyLink allows increased visibility into electricity consumption, automated daily, weekly and monthly reports, and an engineer to look after the site’s behaviour on a daily ongoing basis.

Many of the initiatives revolved around the A/C usage on site, first by reviewing the schedules for all units to reduce weekly operations by 60 hours or 16% of their previous runtime.

Secondly, A/C units were found to be operating overnight with 12 kW more than usual. By resetting the units at the circuit breakers, and then running a schedule update from the BMS through to all the units, the units fell back in line to reflect the schedules that they were programmed for. This issue would occasionally recur when connected to the BMS computer, due to time being reset to original dates and times. This was due to CMOS/BIOS failure, which was eventually resolved by replacing the CMOS backup battery (CR2032), responsible for maintaining the computer time and date.

The EnergyLink sub-metering energy management system was installed at Novotel Wollongong Northbeach in November 2015. The hotel operates 24 hours a day with large common area services for guests as well as over 200 individual rooms. The annual electricity spend is in excess of $40,000 per month. With the increased cost of energy, network and demand charges that were mostly beyond their control, it is important for the hotel to reduce its operating cost and monthly electricity invoice through a low capital expenditure, cost effective solution.

The EnergyLink system provides a circuit by circuit view into the operations of the chillers, HVAC, mechanical plant rooms, pool pump rooms, electric heating, kitchen and lighting. This allows EnergyLink to highlight inefficiencies and then work in conjunction with Novotel’s engineers to improve consumption profiles and operating schedules across the site.

In the first month after installation, EnergyLink identified several critical areas of improvement at the hotel. The first initiative that was implemented achieved large off the invoice savings and was the correction and optimisation of electric duct heaters fed from Fuse Link Box – Level 4. Data from this board showed that there was an inverse relationship with external air temperature. This is unusual as the chiller cooling load is required 24 hours a day for the hotel. Upon further investigation and ruling out electric pool heating, it was discovered that there was a bank of electric duct heaters operating 24 hours a day at a load of 15 kW causing a significant heating cooling conflict. The physical correction of this issue on the 14th of December 2015 by Novotel’s engineers is shown in the image below.

The savings achieved on an annual basis are calculated by the reduced operation (kWh), reduced maximum demand (kVA) and reduced load on the cooling system by removing the heating cooling conflict. The annual consumption reduction is approximately 150,000 kWh and maximum demand reduction is 15 kVA resulting in a combined annual savings of $25,400 or a 4.8% reduction in electricity spend from this immediate correction.