ECO Savings

It's confirmed, Temperzone ECO rooftop packaged units are the product of choice if you’re interested in driving down costs and reducing your carbon footprint.

Large warehousing retail outlets have become increasingly popular over the last 20 years across Australia. These buildings hugely range in size with high ceilings and are air conditioned using large capacity packaged rooftop units with extensive ductwork to distribute air throughout. Many of these buildings still have old R22 systems which are reaching replacement time.

Typically, air conditioning comprises a large proportion of the total running costs for these buildings. Ongoing running costs are a major consideration when equipment is initially specified or evaluated for replacement. Considering these drivers Temperzone developed the ECO range of rooftop package units to provide a highly energy efficient solution.

Temperzone ECO units have been designed utilising a combination of components which work in unison to attain higher annual energy efficiency. These components include backward curved plug fans, variable capacity digital compressors and electronic expansion valves all precisely controlled by highly developed proprietary unit controllers.

The question remained, how efficient are ECO units and how much can be saved?

In response, Temperzone commissioned energy modelling of an office supplies retail outlet to examine the efficiency and environmental impact of three different technologies:

• Old R22 units with a scroll compressor
• Temperzone Standard OPA R410A units
• Temperzone ECO OPA units (R410A + Plug Fans + EEV + Digital Scroll Compressor)

Using ACADs Camel and ACADS Beaver software, annual energy consumption was modelled on identical warehouse configurations in Sydney, Melbourne and Brisbane each with a total heat load of 148kW. Energy modelling was based on a system consisting of 3 X OPA 550 rooftop units or their R22 equivalents. (*For a summary of findings and further details of the study configuration see the tables and notes following the article.)

The modelling results show that while modern R410A package units offer significant energy savings over older R22 units, Temperzone ECO OPA units provided a twofold increase in efficiency in all three locations. In Melbourne this amounted to annual energy savings of 66% over the R22 equivalent - a significant reduction in running costs!

Expanding on the Melbourne energy saving figures, if we were to factor in a commercial electricity cost of $0.15 per kWh we would expect annual running cost savings of $10,583 over the R22 system. Applying these savings over an estimated 15 year lifetime of the units would amount to a savings of $150,838. Furthermore, if we were to factor in 10 stores within the state of Victoria the savings would then be in the millions! Now ECO units are starting to prove their worth.

Of course these energy savings also translate into a much smaller carbon footprint. The CO2 emissions due to general electricity consumption may surprise you. Melbourne has an emissions factor of 1.17 per kWh of electricity consumed. Therefore, the Melbourne store with an existing R22 system is responsible for a staggering 125 tonnes of CO2 emissions annually. In contrast, ECO units with a 66% reduction in electricity consumption are responsible for only 43 tonnes of CO2 emissions annually.

To put this in perspective we can compare how this would impact on our ecosystem. A mature 30 year old pine tree will absorb 87.5kg of CO2 each year. At this rate it would take over 1,400 trees a whole year to absorb the CO2 emissions which one Melbourne store with an R22 system is responsible for annually. ECO units as an environmentally responsible choice allow individual companies to measurably play their part in reducing the impact of global warming.

Temperzone offer a complete range of ECO units to suit most projects. To find out more about how you can benefit from ECO rooftop package units or to learn more about this study please call your Temperzone representative.

Modelling Configuration Notes:
Configuration assumed to be 3 x OPA550 units (or R22 equivalent)
All locations hours of operation: 5840 hours per year (16hr/day, 365 days per year)
Sydney Peak cooling load – 115kW GTH/93.6kW GTSH, (ACADS CAMEL 5.10.2)
Peak cooling load – 106kW GTH/101kW GTSH, (ACADS CAMEL 5.10.2)
Brisbane Peak cooling load – 127kW GTH/95.4kW GTSH, (ACADS CAMEL 5.10.2)
Energy calculations using ACADS BEAVER 7.11.0
Sydney CO2 Emissions based on NSW emissions factor of 0.87
Melbourne CO2 Emissions based on NSW emissions factor of 1.17
Brisbane CO2 Emissions based on NSW emissions factor of 0.82
Cooling coil capacity standardised to 130.8kW
Sydney cooling assessed @ 25C, heating @ 8C
Melbourne cooling assessed @ 25C, heating @ 5C
Brisbane cooling assessed @ 25C, heating @ 10C