Advanced Energy Efficiency, Lecture 2: Industry - Rocky Mountain ...
Advanced Energy Efficiency, Lecture 2: Industry - Rocky Mountain ...
Advanced Energy Efficiency, Lecture 2: Industry - Rocky Mountain ...
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
AC vs. DC power supplies—so far,<br />
determined by cultures, not data<br />
◊ Swiss data centers in 2001 used about half the<br />
kWh for telco switching on a DC bus as for<br />
comparable internet apps on an AC bus<br />
◊ LBNL (06) measured 19%, plausibly 28%,<br />
savings from DC supply architecture<br />
◊ Japanese data centers are mostly designed<br />
and built by a telco firm, NTT-F, whose<br />
experience with its 48-VDC bus in >10 4<br />
installations shows order-of-magnitude higher<br />
uptime and far lower losses than AC<br />
<br />
Most US designers would use hundreds of V to shrink bus<br />
◊ PS: Why not a “distributed UPS” w/local LVDC<br />
batteries, like a bunch of laptops?
Change language