Visitors to the Singapore Botanic Gardens can stay cool, thanks to a newly installed cooling system - and without feeling too guilty about harming the environment.
The system, known as Green Aircon Flex, has been installed since last December in the open-air National Orchid Garden within the grounds. It is the first time the cooling system has been installed outside Japan.
Developed by Japanese electronics giant Panasonic, the system is said to cool down the surroundings without worsening the urban heat island effect. This is mainly because it features an improved nozzle technology that consumes less power.
By using a two-fluid nozzle to generate mist from water and air, the size of the mist particle emitted is about six micrometres.
Conventionally, this type of two-fluid nozzle is limited by large-scale infrastructure and high energy consumption. It is also not possible to install the control panel outdoors.
The technology allows Panasonic to develop a compact and energy-saving system for outdoor use. It is estimated to use up to 70 per cent less energy compared with conventional two-fluid mist systems.
Panasonic's system also emits less waste heat, which is heat produced by a machine as a by-product.
The cooling system's waste heat is generated only from the compressor, while an outdoor heat pump air-conditioning unit emits waste heat generated from both the compressor and the cooling component.
The power consumption of the Green Aircon Flex system ranges from 1.1kW to 2kW, depending on the configuration. The system has been used in Japan, such as at shopping arcades and train stations.
Generally, the system is said to be able to make a person standing about 60cm from the mist nozzle feel cooler by up to 4 deg C.
Currently, four of the cooling devices are installed in the Mist Garden, and one in a resting pavilion. They will be used at the National Orchid Garden until the end of June, subject to a new agreement between the Singapore Botanic Gardens and Panasonic. Three devices have also been installed at the Jurong Lake Gardens.
Panasonic is keen to introduce the Green Aircon Flex in more outdoor areas in Singapore and other countries in the region.
The price depends on the size of the project, the complexity of the installation and the maintenance required. One system with a single control box that has up to 10 nozzles may cost about $25,000.