Data Centre Cooling - Airflow
Regardless of the operating standards it must be remembered that IT equipment requires a substantial amount of air to keep it cool. A typical 100kW data centre requires a minimum of 8.5 cubic metres per second – this is over 250 million cubic metres of air per annum! The lowest energy ventilation systems use Electrically Commutated (EC) axial fans. The 100kW data centre can be ventilated using EC fans which consume less than 5kW. This means the system will only add a maximum of 0.05 to the PUE of the data centre. This is a key stage in achieving a PUE of less than 1.1.
Minimising fan speeds greatly reduces energy use. As a rule of thumb a fan running at half speed uses 12.5% of the full speed power. When data centres are partly populated then variable speed EC fans exploit this and energy use is even further improved.