Qatar Showpiece Stadium – Doha 2010
In 2010 the Qatari government commissioned the construction of a scaled-down football stadium in Doha to demonstrate that the harsh Qatari summer – when temperatures can reach 45°C and relative humidity levels can reach 95% – need not be a barrier to its plans to host the football World Cup in 2022.
The 500-seat stadium uses cutting-edge technologies to create a controlled microclimate over and around the football field, and in other public spaces. It is also intended to promote sustainability, using environmentally friendly technologies. The project had to be environmentally sound with a small carbon footprint, so it was designed to run from electricity generated by a nearby solar farm, consisting of an array of solar photovoltaic panels and a solar thermal mirror field. The panels are connected to the stadium’s electrical system and to the local electricity grid. The plant will export electrical energy throughout the year, with the amount of solar electricity generated exceeding the amount of electricity imported for events, thus making the facility zero-carbon in terms of electricity.
Dessicant Dry Air of Morecambe was awarded the contract to supply the AHUs, pump sets and a high pressure hot water (HPHW) system to control the water pressure in the mirror field and in the supply to the absorption chiller. The HPHW system regenerates lithium bromide coolant to chill the airflow.
Dessicant Dry Air sub-contracted Bromsgrove-based Siam Control and Automation to supply the controls for the HPHW system. These ensure that the pressure in the network of pipes around the mirror field is maintained at a constant 12 bar. An Idec Pentra PLC was chosen for this duty because of its advanced PID and communication capabilities. The PLC was programmed to control two of the inverters in a duty/standby arrangement that maintains the water pressure during the wide variations in temperature as the sun travels across the sky.The auto-tuning function of the PLC’s PID algorithm ensures that the speed of the inverters and the subsequent system pressure control is as smooth as possible. Modbus communications link the PLC and inverters to a Renu Electronics 5.6” TFT touchscreen HMI which is used for input, process visualisation and communications with a site-wide building management system. The HMI is configured as a Modbus master to facilitate communication between the inverters, while a second communication port is available as a Modbus slave to the BMS.
The mini-stadium was completed by the end of August 2010 and was able to keep maximum temperatures well below the guidelines issued by FIFA’s medical committee to avoid players suffering significant heat stress. It also beat Ashrae comfort standards for spectators. During an inspection visit by FIFA officials, the temperature on the pitch was recorded as 23°C, despite the external temperature having reached 44°C just two hours before.