Nokia Siemens Networks says its SiteStar cooling cabinet can reduce battery cooling costs by 95% and extend the operating life of batteries by as much as three fold. SiteStar is basically a dedicated cabinet designed to contain the battery of cell sites, instead of traditional solutions using conventional air-conditioner-cooled enclosures for the whole site, and is part of NSN’s Smart Site solution set.
According to NSN, SiteStar is ideal for countries with extreme weather – both hot and cold weather – and for emerging markets with dodgy power grids that might battery back-up essential. The solutions should work nicely with alternative energy sites too.
“SiteStar can replace expensive shelters and power hungry air conditioners which are often needed only for battery cooling,” said Prashant Agnihotri, Head of GSM/EDGE Product Management, Radio Access, Nokia Siemens Networks. “It eliminates the need for expensive indoor sites, while reducing the OPEX of an outdoor site thereby helping an operator not only reduce the cost of roll out and operation, but also its CO2 footprint.”
For the last couple of years, many operators around the world has experimented turning up the temperature of their network equipment from 20-22 degrees Celsius, to as high as 30 degrees Celsius to reduce cooling costs. Many have found that the network equipment worked fine at the higher temperature.
SiteStar now addresses the situation of the battery pack in such environments. As more operators turn up the temperature, the battery themselves, which previously are installed inside the same enclosure of the network equipment, would degrade.
According to NSN, the life of a battery is inversely proportional to the temperature under which it operates, and is reduced by 50% with a mere 10 degrees Celsius increase above the optimal temperature of 20 degrees Celsius. With the SiteStar, operators can run the network equipment at higher temperatures and still keep their batteries cool.
This is yet another example of isolating and supply cooling capacity to where it is needed, such as the hot aisle/cold aisle concept for data centres.
The SiteStar cabinet is scheduled for commercial launch in the third quarter of 2009. The cabinet’s operating temperature range is from -40 to +50 degrees Celsius, and uses 40W to keep the batteries cool, or warm.