Concepts for Energy Efficient Cooling

While solar cooling is especially well suited for new projects and buildings, solar-assisted cooling (SAC) also provides the ability to reduce the electrical consumption of existing compression cooling systems, thereby reducing the carbon footprint.

As the name implies, SAC systems employs solar thermal-driven absorption chillers, which assist electrical compression cooling systems. The chilled water supplied by hot water-driven absorption chillers helps to “pre-cool” the chilled water cycle of the compression chiller(s). This “pre-cooling” reduces the deltaT of the electrical chiller(s), thus significantly reducing the overall electrical consumption of the system.

Among other things, SAC systems provide three key customer-specific advantages:

1. SAC provides building owners and investors with the opportunity to upgrade existing cooling systems to “green building” standards, while at the same time significantly reducing the operational cooling costs.
2. SAC systems help to reduce the electrical load of compression chillers during daytime peak demands and reducing total electrical consumption.
3. Absorption chillers in SAC systems support air-cooled compression chillers in arid climate zones affected by a rise in ambient temperatures: since the efficiency of air-cooled compression chillers is drastically reduced by ambient temperatures above 40°C, SAC support the efficient operation of air-cooled chiller systems.

YAZAKI Aroace WFC series is especially suitable for solar cooling, as it requires the lowest driving energy temperature (70°C) in absorption technology.

Advantages of solar-assisted cooling applications:

• Driving energy for absorption chillers is taken from renewable energy (solar-thermal hot water) and thus CO2-neutral.
• Reduction of electrical consumption and thus of cooling-related CO2 emissions.
• Possibility to update existing cooling technology in order to meet new energy efficiency requirements.
• Lower retrofitting costs of SAC makes for an affordable alternative to full-scale solar-cooling systems due to reduced solar surface requirements.
• Facilitates the use of renewable cooling for existing properties.
• Reducing the electrical consumption of compression chillers in SAC alleviates the strain on electricity grids by decreasing cooling-related demand peaks.
• SAC compensates for the “air-cooling”-related disadvantages of compression chillers, enabling compression-cooling operations in even the harshest climates.

YAZAKI provides the chiller/heater unit only. If you need more information about other equipment such as cooling towers, valves etc. please contact the equipment manufacturer directly.