Sry for the top post... As more facilities are built/retrofitted with an eye toward overall efficiency using CCHP, we will start seeing more facilities (like Syracuse U's new datacenter) use systems like the Capstone turbines for primary power/secure power/CCHP. The main grid will become the backup. Not saying this approach replaces the need for batteries or some other storage device such as a flywheel system.. "This Year InGuard has Stopped 159,953,000 Spam E-Mails and 573,000 Viruses... Do you have http://www.inline.com/SolutionsbyTechnology/InternetDataCenter/InGuard/tabid..." InLine> bryan king | Internet Department Director InLine> Solutions Through Technology 600 Lakeshore Pkwy Birmingham AL, 35209 205-278-8139 [p] 205-314-7729[f] bking@inline.com www.InLine.com All Quotes from InLine are only valid for 30 days. This message and any attached files may contain confidential information and are intended solely for the message recipient. If you are not the message recipient you are notified that disclosing, copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited. E-mail transmission cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore does not accept liability for any errors or omissions in the contents of this message, which arise as a result of e-mail transmission. If verification is required please request a hard-copy version. From: Owen DeLong [mailto:owen@delong.com] Sent: Wednesday, November 04, 2009 4:18 PM To: Raphael Carrier Cc: nanog@nanog.org; Joe Greco Subject: Re: HE.net, Fremont-2 outage? On Nov 4, 2009, at 2:08 PM, Raphael Carrier wrote:
I know you have a rather higher faith in batteries than some of us, but practical experience suggests that batteries are merely a mostly- reliable technology.
Agreed batteries are unreliable, an alternative to battery based UPS are flywheel energy storage devices, they come either as an integrated solution with the diesel generator (i think cat offers such a package) or as a standalone UPS (see: www.pentadyne.com/uploads/18/File/Pentadyne-VSS-Brochure.pdf)
Apparently you do not remember 365 Main... Batteries are reliable. Flywheels are reliable. Both require proper maintenance and proper procedures to handle corner cases (like the multiple-outage corner-case that took out 365 main). Both have their issues. In my experience working at and with a variety of datacenters, I have to day that I have had generally better luck with batteries than flywheels, but, the key difference that suggests flywheels could actually be better technology is this: About 50% of battery failures traced back to human factors. 100% of the flywheel failures I experienced were human factors related. Owen Speaking as an individual, not representing any affiliation.