BubbleZERO Laboratory

The BubbleZERO is the laboratory of the Low Exergy research module at the first phase of FCL that allows to test novel systems for cooling, dehumidification and ventilation and their control under real life ambient and operating conditions in Singapore.

The original objective was to design a space to evaluate the performance of low exergy building systems developed in Switzerland in the tropical climate of Singapore. Low exergy (LowEx) systems optimize supply temperatures to maximize performance. The basic systems were installed at ETH Zurich and shipped and erected as a laboratory in Singapore. This approach resulted in a novel laboratory environment containing hydronic radiant cooling panels and decentralized air supply units, along with a self-shading, inflated “Bubble” skin, experimental low emissivity (LowE) glazing, LED lighting, wireless sensors and distributed control (Bruelisauer et al. 2013).

The BubbleZERO laboratory is used by the PhD students of the Low Exergy research module for measurements, testing of new components and for the evaluation of simulation models. In addition, it serves as a showroom for LowEx technology in Singapore.

The setup allows to study the effectiveness and performance of a setup that covers the sensible and latent part (dehumidification) of the cooling load with different systems. Air is dehumidified in decentralized ventilation units. Sensible cooling is provided by a hydronic radiant system that can be operated with higher supply temperatures than required for dehumidification. A chiller’s performance is directly related to the temperature it has to supply and the adjustment of the supply temperature to the actual demand increases the overall performance of the setup and thereby reduces the electricity consumption of the cooling system. It is the first time that this technology has been combined and installed in such a way not just for Singapore but also for the whole of Asia.

A wireless sensor network has been developed that allows for a distributed sensing and control of the technical systems (Li et al. 2013). It allows to locally control condensation and energy consumption thereby increasing accuracy and performance of the system.

The operation of the laboratory has shown the feasibility of the technology in a tropic climate (Iyengar et al. 2013). Initial results from the operation have shown that humidity is controlled effectively utilizing a new cooling coil setup within the decentralized ventilation units (Saber et al. 2013) and that the radiant panel system operating in conjunction with wireless sensors and distributed control reduces the risk of condensation with varying indoor conditions.

References

• Bruelisauer, M. et al., 2013. BubbleZERO-Design, construction and operation of a transportable research laboratory for low exergy building systems evaluation in the tropics. Energies, 6(9), pp.4551–4571. Available at: external pagehttp://www.mdpi.com/1996-1073/6/9/4551call_made.
• Iyengar, Rupesh, Esmail Saber, Forrest Meggers and Hansjurg Leibundgut (2013). ‘The Feasibility of Performing High Temperature Radiant Cooling in Tropical Buildings When Coupled with a Decentralised Ventilation System’, HVAC & R Research Journal.
• Li, Cheng, Forrest Meggers, Mo Li, Jithendrian Sundaravaradan, Fei Xue, Hock Beng Lim and Arno Schlueter (2013). ‘BubbleSense: Wireless Sensor Network Based Intelligent Building Monitoring’, in Proceedings of ICT4S 2013, eds. Lorenz M. Hilty, Bernard Aebischer, Göran Andersson, and Wolfgang Lohmann, 159–166, paper presented at First International Conference on Information and Communication Technologies for Sustainability (ICT4S 2013), Zurich, Switzerland.
• Saber, Esmail, Forrest Meggers and Rupesh Iyengar (2013). ‘The Potential of Low Exergy Building Systems in the Tropics – Prototype Evaluation from the BubbleZERO in Singapore’, in Proceedings of Clima 2013: Energy Efficient, Smart and Healthy Buildings, paper presented at 11th REHVA World Congress and 8th International Conference on IAQVEC (CLIMA 2013), Prague, Czech Republic.