SILICON
SILIC
CHIP
www.siliconchip.com.au
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Leo Simpson, B.Bus., FAICD
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Nicholas Vinen
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John Clarke, B.E.(Elec.)
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SILICON CHIP is published 12 times
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ISSN 1030-2662
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2 Silicon Chip
Publisher’s Letter
Big Brother can control your aircon
Australians love air-conditioning. Over the last few
years, more and more domestic aircons have been
installed, to the point where market penetration is
now approaching 70% or more in some cities. And
why not, Australia has hot summers and if people
want and can afford air-conditioning, then there is
no particular reason why they shouldn’t have it.
In fact, most Australian cities have just sweltered
through a very hot Summer and it can be particularly difficult to get to sleep on hot, humid nights. As someone who does
not have air-conditioning at home, I can testify to that. That has made me
consider having air-conditioning installed so that we can be more comfortable next summer.
But in thinking along these lines, I and millions of other Australians are
contributing to an ever-increasing peak demand for electricity in those very
hot summer periods and our diminishing grid cannot cope, especially with
the trend to renewable energy sources which often do not contribute when
they are most needed. For example, if a large high pressure system is stationary over the southern states, as can happen in the hottest summer weeks,
there may be very little wind power generation. And solar panels drop their
power output just when the evening peak demand is ramping up.
Ultimately, if there is insufficient grid capacity, the AEMO (Australian Energy
Market Operator) can demand load shedding which means that consumers get
blackouts. Great. So there you are, enjoying your hard-earned air-conditioning
and all the other benefits of a modern economy and the electricity goes off
and you don’t know how long the blackout might last. This is set to happen
much more frequently in South Australia but other states will not be immune.
In their “wisdom”, the authorities have come up with another scheme to
control peak domestic demand and it is called, ironically, a DRED or Demand
Response Enable Device. It is a system to switch off or reduce the output of
your aircon and is described in this month’s issue by Dr David Maddison.
DRED-compatible aircons can have three Demand Response Modes,
referred to as DRM1, DRM2 & DRM3. DRM1 completely switches off the
compressor while leaving the fan running so without warning you will be
left sweltering and wondering if your aircon has failed. DRM2 and DRM3
are modes which reduce the compressor’s output and depending on how
hot it is outside, you may not notice much change.
Virtually all aircons now being sold in Australia are DRM-compatible
but most will require an additional module to be installed by the electricity
retailer to enable it to be controllable. Some energy retailers are actively
encouraging consumers to opt-in to DRED schemes with non-threatening
slogans such as CoolSaver or PeakSmart and with one-off incentive payments.
But don’t opt in; not if you know what’s good for you! The incentive
payment (typically a maximum of $400) is simply inadequate. It means that
when you really want air-conditioning, it could be switched off. Worse still,
if you have a grid-connected solar panel system, you could be subjected to
the bitter irony of having your solar panels feeding the grid with power while
you are deprived of air-conditioning. How happy would you be?
Right now, DRED is not compulsory but if Australia’s grid becomes more
crippled by having to accept more renewable energy input at the expense
of good old reliable coal-fired base load power stations, you can bet that
DRED will become compulsory for everyone who owns a compatible aircon.
Mind you, some technically savvy consumers might then decide to take
matters into their own hands and figure out a way to disable DRED. Who
could blame them?
Leo Simpson
siliconchip.com.au
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