SOLAR "COMMERCIAL AIR-CONDITIONING" SYSTEMS
OUR ACHIEVEMENTS AND OUR GOALS
On a hot Australian summer’s day when the sun is blazing down the heat is oppressive for all plants and creatures including you. It would be nice if someone could turn at least some of this heat into cooling? A cool idea indeed! Well much more than just a cool idea, this is now a cool reality.
• Making our life more comfortable
• Making a lot of economic sense
• Improving the environment
A commercially viable, efficient, mature and reliable solar air-conditioning package is now available as a result of our research and development. Instead of siphoning away mains power on the hottest days, causing power blackouts and worse, GreenLand Systems solar air-conditioning rely on solar energy. And the hotter the Australian sunshine the more cooling power it will provide.
Meeting Australia’s electric power demand on the hottest days, when electric powered air-conditioners overwhelm the grid capacity, is a huge problem for the Australian power network. Over the last few years, partly due to hotter climate, Australian peak energy demand has been growing much faster than base power demand, making the problem worse.
GreenLand Systems solar air-conditioning is most suitable for cooling medium to large commercial buildings, hospitals, hotels, factories, community buildings, schools, nurseries, etc., providing pleasant living conditions from a totally renewable carbon-free source. The main benefits brought by GreenLand Systems solar air-conditioning:
• Slash carbon emissions
• Significantly reduce power grid load. The importance of cutting peak-power load is impossible to over emphasize
• Cut your energy bills forever
• Make full use of additional summer energy available from solar collectors
Australia’s abundant and predictable sunshine pattern on one hand, and great difficulties of the power grid meeting reliably the peak load demand, make Australia an ideal place for the use of solar air-conditioning. After two years of intense R&D by our engineering team, and after thorough system reliability and performance evaluation, we are confidently launching GreenLand Systems solar air-conditioning.
SOLAR AIR-CONDITIONING SYSTEM - OPERATING PRINCIPLE
More than 98.5% of all energy needed to run solar air-conditioning comes directly from the sun. Only a tiny amount of electric power is needed for its electronic control system, pumps, valves and other devices. The higher the water temperature supplied to the solar chiller, the more efficiently the cooling system will perform. This is why GreenLand Systems solar air-conditioning relies on highly efficient GLS100 single glass full vacuum tube solar collectors.
Solar collectors GLS100 will deliver hot water efficiently during their entire service life, assuring continuous peak performance of the solar air-conditioning. Therefore, highly efficient and reliable solar collector field is a crucial system component of any solar air-conditioning. GreenLand Systems solar collectors GLS100-16 and GLS100-16DF have been developed especially for solar air-conditioning application service.
Please check our brochure “Comparison of various Solar Collectors” for more information on GLS100 series of single glass full vacuum tube solar collectors.
GL-100-16 evacuated solar tubes
THE SOLAR COOLING MACHINE OPERATING PRINCIPLE
The physical principle of generating solar cooling power is in some respect similar to the operating principle of conventional condenser (compressor) type air-conditioning. Both systems rely on GreenLand Systems Full Vacuum Single Glass Heat Pipe Collector Picture liquid-to-vapor phase change energy of the refrigerant to attract heat (i.e. to produce cooling effect). The way the two systems achieve this, though, is quite different. While the condenser machine achieves cooling effect by expanding compressed refrigerant into a low-pressure chamber, the solar cooling machine relies on the absorbing action of the absorbent to create near-vacuum inside its chamber. In near-vacuum, the refrigerant will evaporate at a very low temperature, removing latent heat from the refrigerant (i.e. producing cooling effect). This happens at a temperature significantly lower than the refrigerant’s evaporation temperature at atmospheric pressure. A cooling effect is thus achieved at usefully low refrigerant temperatures, making this principle practical for commercial use.
Heat supply from a field of GLS solar collectors to the solar air-conditioning system is required not to directly provide the cooling action directly, but to maintain the absorbent concentration. This ensures that low chamber pressure and low evaporation temperature of the refrigerant are maintained.
SOLAR AIR-CONDITIONING - PERFORMANCE
A well designed and correctly used solar air-conditioning will almost totally eliminate the running costs of space-cooling.
Following is a very simple example of solar air-conditioning energy balance calculation:
• Peak-month summer solar input: 25.4MJ/m2/day (Canberra, ACT)
• Each GreenLand Systems solar collector GL100-16DF can under these conditions generate about 40MJ/day [11.1kWh/day], at optimum output fluid temperature
• Assuming the building’s daily cooling load of 0.50 kWh/m2, each solar collector GLS100-16DF can fully support about 13 to 15m2 of building floor space with solar cooling.
Each Greenland Systems solar collector GL100-16DF can support about 15 m² of building floor space with solar cooling during peak summer heat.
GreenLand Systems solar air-conditioning systems are particularly suitable for commercial and large domestic installations requiring continuous and reliable cooling power.
Although the installation cost of GreenLand Systems solar air-conditioning could be marginally higher than the cost of a comparable capacity mains-powered condenser system, one should not lose sight of the fact that installing a GreenLand Systems solar air-conditioning will bring cost-free zero-emission space cooling and heating comfort for the life of the system, without sending peak power load into stressful levels.
MOST COST EFFECTIVE, MOST VERSATILE: DUAL-PURPOSE SOLAR INSTALLATION
As we all know, daily solar irradiance varies with seasons. In many parts of Australia, space heating is often required in winter while in summer space cooling is often required. Huge amounts of fossil fuel is consumed annually supporting both.
The amount of solar energy supplied in Sydney during the peak summer is about 2.6 times more than during winter. Many big cities of Australia have similar solar input ratio.
Space cooling usually consumes more energy annually than space heating in many populated parts of Australia. Considering that no space cooling should be required during winter, as no space heating is required during summer – it follows that a well matched combined system will ensure nearly full use of the entire solar collector field during much of the year; supporting most of the space cooling load in summer and most space heating load in winter. Such combined use of solar installation usually brings the best financial return.
Our comprehensive solar energy modelling repeatedly confirms that, thanks to its special solar disposition, Australia is one of the most suitable countries on Earth for use of solar air-conditioning. Graph below shows historical monthly solar irradiance per square metre in Sydney, NSW.
Area below the yellow line represents typical portion of energy, required to meet the heating load demand at different times of the year.
Shaded area above this line represents the spare solar energy of an existing solar heating system, which is freely available for the purpose of solar air-conditioning in summer?
FIGURE 3: SOLAR AIR CONDITIONING SYSTEM WITH INTEGRATED CLOSE-TYPE COOLING TOWER
EXAMPLE - SPECIFICATIONS
GreenLand Systems solar air-conditioning system refrigeration capacity:
• 30 USRT (105kW) to 992USRT (3488kW).
• Suitable for commercial or large domestic space cooling.
We also provide modular Stainless Steel storage tanks for hot and cold water.
FIGURE 4: CONFIGURATION EXAMPLE OF MEDIUM SIZE COMMERCIAL SOLAR AIR-CONDITIONING
MODULAR STAINLESS STEEL STORAGE TANK
GreenLand Systems Modular Stainless Steel Storage Tank is available in “insulated” and “non insulated” versions, suitable for storage of hot or chilled water. The insulated version has PU-clad Stainless Steel insulating panels attached on the outside. Thickness of hard PU insulating layer on the inside of each insulating panel is either 70mm or 100mm. Made from Stainless Steel, with or without internal heat exchanger, GLS modular tank can be supplied to the building site on pallets. Because this Modular Stainless Steel Tank is assembled on its final location, it is especially convenient for use in existing buildings with limited site access. Its simple bolt-together construction design allows this tank to be assembled by persons with only limited training.
FIGURE 5: MODULAR STAINLESS STEEL COMMERCIAL STORAGE TANK