"Bumblebee" uses sun to cool buildings

Big maschine with pipes

Solar Cooling System "Bumblebee". Photo: GIZ

The new Solar Cooling System was successfully installed on top of the GJU building in Madaba and will be handed over from the joint project partners the Jordanian Ministry of Environment and the GIZ to the site owner GJU. Within close technology cooperation, the operation and maintenance team of the GJU worked hand in hand with TU Berlin, the provider of the bumblebee, HEAT, a technical consulting firm specialized on refrigeration and air-conditioning and Millennium Energy Industries, the local engineering firm, to set up the cooling system and integrate it into the existing solar thermal field of the GJU.

This demonstration project is part of the "Solar Cooling for Industry and Commerce" (SCIC) project implemented by the Jordanian Ministry of Environment's (MoEnv) National Ozone Unit (NOU) and the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH, on behalf of the German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) and was funded by the International Climate Initiative (IKI).

The project is considered an important first step within the scheme to promote climate friendly cooling technologies in Jordan through the use of natural, non-ozone-depleting, and climate-friendly cooling agents, as well as benefiting from the high levels of solar irradiation in the region. The system developed by TU Berlin was integrated into the pre-existing air cooling system at the GJU and is able to deliver cooling power at a COP of 0,75.

In short, the technology of "Solar absorption cooling" uses solar heat collected by solar collectors to extract the refrigerant from the refrigerant/absorber mixture at high pressure and deliver it further on to the condenser as in typical refrigeration cycles. Energy savings using this approach are achieved by relying on solar heat energy combined with liquid pumps rather than the conventional compressor in order to achieve the pressure difference between the condenser and the evaporator. In addition, absorption systems use different kinds of refrigerants which have no adverse effects on the environment or ozone depletion, typically lithium bromide as absorbent and water as the refrigerant.

Millennium Energy Industries will provide an on-site operational instruction training program to the GJU's staff for the handling of the chiller system in relation to the control system and the data monitoring.