AAWC building is a newly reconstructed five-storey building with approximately 3300m2 total area. Space heating is based on fan-coils system and 300kWgas boiler. The estimated cooling load of the building is about 150kW. In summer time the ambient temperature in Yerevan often reaches 400C. For cooling needs single effect hot water lithium bromide absorption chiller YORK Model YIA-HW-1A1-50-C-S-C has been installed in the basement of the building near the gas boiler. The chiller is shown on Figure 3.

The absorption chiller has nominal cooling capacity of 420kW and is connected to the VXT 70 cooling tower with 400kW capacity placed on the roof top of the building 25m above the boiler house. The cooling tower can be seen on the roof of the building on the right side of the PV array (Fig.1).

In cooling season the gas boiler provides hot water to the absorption chiller installed inside the same boiler house. Chilled water enters the fan-coils system of the building. The gas boiler provides hot water for chiller’s generator loop at 90°C/70°C supply/return temperature. For similar applications the hot water could be supplied by appropriate solar water heating system with gas boiler back-up. The water temperature in absorber/condenser-cooling tower loop is 290C/ 330C, and chilled water supply/return temperature is 80C/120C.

The power need of the chiller is about 24kW including chiller’s solution, refrigerant, purge pumps and cooling tower fan and water pump. A conventional compression chiller with

similar cooling capacity would require almost 10 times more electric power and, consequently, too large size cabling from building to transformer sub-station. .

Absorption chiller is an attractive energy efficiency solution, particularly when gas or solar heat source is available.

The absorption chiller has been tested with building’s fan-coils system and commissioned in June2008. The building is still under renovation and at the moment there is no need for absorption chiller which is kept in standby mode.

2. Conclusion

The 10kW grid connected BIPV station and 420kW lithium bromide absorption chiller are installed, tested, and ready for operation and will be monitored during operation.

Their performance monitoring data, particularly related to the power consumption and hot water supplied to absorption chiller, can be used when considering combinations of solar PV and/or water heating system with similar absorption chiller. The performance of the liquid absorption chiller can be compared in the same climatic conditions with the performance of the solar driven desiccant cooling system operating in Yerevan since February 2002 [2].

The combination of the grid connected PV power station and lithium bromide absorption chiller on the same place provides also the opportunity for determination of produced PV power’s

contribution to chiller’s power consumption in different cooling conditions. The results of the study can be useful for countries with similar climate conditions.

References

[1] http://www. renewableenergyarmenia. am

[2] EU INCO-COPERNICUS Programme. Design and Installation of Solar Driven Desiccant Cooling Demonstration System, Contract #ICOP-DEMO-4034/98. INETI (PT), AUA (AM), FhG-ISE (D), CONTACT-A (AM), INTERSOLARCENTER (RU), Final Report, 2002