Emerging UPS Standby Power Sources
January 12th, 2010 By: Kevin Normandeau
Four Promising Alternatives to the Lead Acid Battery. Though an uninterruptible power supply (UPS) performs many important functions, most users value them chiefly for the emergency energy they provide during a power outage. UPSs give IT personnel the time they need to protect sensitive equipment and data from the effects of an electrical service interruption by shutting down systems in an orderly fashion or starting a backup generator. This white paper from Eaton discusses how a viable alternative to the lead acid battery is closer than ever before.
Today, most UPS products use lead acid batteries to store emergency standby power. A proven technology with many decades of successful service in a variety of industrial settings, the lead acid battery remains the most cost-effective energy storage solution as measured by dollars per minute of backup time.
Yet despite these merits, lead acid batteries are unpopular among data center managers due to their size, weight, maintenance requirements, toxic contents and relatively short lifespan, among other issues.
As a result, UPS makers have long been searching for an alternative standby power technology that’s smaller, simpler and “greener” than lead acid batteries, yet no more expensive to operate.Today, that hunt just may be nearing its end. Several exciting new standby power solutions, all rapidly approaching mainstream commercial viability, appear poised to give the lead acid battery a run for its money. This white paper will explore the strengths, weaknesses and future prospects of four such technologies: Flywheels, ultracapacitors, fuel cells and lithium ion batteries.
At the moment only large SOFC or MCFC can be used as UPS. In my oppinion soon it will be large market – especially for hospitals as an alternative to conventional diesel ones.
Alternatives to lead acid batteries are not only a coming trend, but are well proven in hundreds of installations of carbon fiber flywheels with our installed base. They provide a reliable bridge to standby generators without the need for batteries, and in many cases are used to “harden” or extend the life of a lead acid battery by taking the burden of the short outages and transfers during routine generator tests away from the battery itself. Beyond flywheels, the commercialization of Lithium Ion and other battery technologies is also occuring today.
Supposedly one of the killers of lead-acid batteries is frequent, short power outages. If an ultracapacitor with a few seconds of power was integrated with the UPS, the batteries could last much longer.
Of course, this puts a big crimp in the sale of replacement batteries or UPSes, so we are unlikely to see this innovation from companies with big investments in traditional UPSes.