[LINK] NBN and Batteries

Paul Brooks pbrooks-link at layer10.com.au
Wed Feb 23 16:53:00 AEDT 2011

On 23/02/2011 3:11 PM, Tom Koltai wrote:
> Interestingly enough, if they left the copper in the ground, it could
> provide a back up current for the NBN so that in the event of a power
> failure at the local suburb level, Power could be supplied to the fibre
> (kerbside MDF Node) and the home via the copper....
> What a revolutionary idea...

Well, there is no kerbside MDF node that needs power, only a completely passive
dark-fibre splitter - but the argument about powering the ONT at the house is worth

One of the original justifications for Telstra deploying the FTTN network originally
is that this would alow them to decommission and sell off the valuable real-estate
space that the current exchange buildings are sitting on - the NBN should still
provide this option to Telstra, as long as the NBN doesn't decide to use corners of
existing exchange buildings as their regional switching hubs.
These buildings are where the central batteries and generators and fuel-stores are
located, so if Telstra sell off the exchange buildings there won't be anything left to
inject power into the copper loops at the exchange end.

Also, another justification for the fibre network is that apparently much of the
Testra copper is in a poor state, and the maintenance costs are crippling high -
recall Telstra thmselves stating in Senate Estimates that the Telstra copper networks
was "at 5 minutes to midnight".
If the home network terminals are powered from line-current over the copper pairs,
then that copper network wll still need to be maintained, including all the millions
of dollars they spend each month and year carting trucks of compressed air cylinders
around to keep leaky pressurising jackets pressurised - which almost defeats the point
of pulling fibre through.

If you can get past these two issues, powering from the obsolete copper line might be
worth pursuing.

I'm a much bigger fan of local powering, for those that need it or want it - perhaps
linked (as we discussed Tom, and I think I raised it a few months ago) to a seed/pilot
solar panel installation to provide an in-house continuous power solution if the mains
fails, that can also be used to power the cordless telephone and ATA box or IP
telephone handset, all of which are currently plugged into a mains power point and
won't be backed up by either the ONT battery or the small current available from the
exchange on a copper telephone pair.

For so many people there is no point in providing backup power to the NBN
terminal,because the home user doesn't have any telephone handset that can plug into
the terminal that will run without mains power. The NBN doesn't need a builtin backup
battery, it needs an external UPS with several 240V power-points.

There are other arguments about not cutting off the copper when a new network is
installed - this was to counter FUD around at the time about the exchange-based copper
interfereing with FTTN services, or vice-versa -


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