MEA
41 Vine Street Magill SA 5072
Phone: 08 8332 9044
Fax: 08 8332 9577
[email protected]
www.mea.com.au
MEA and the Development of Wind Systems
managed the whole thing in an ancient Land Rover (and
occasionally on horseback). I won the contract for the
noble sum of $9000 per year – apparently no other
electronic engineers with wife and kinder wanted to live
below the poverty line for three years to set up wind
monitoring sites around South Australia.
Dr. Andrew Skinner, Engineering Director.
Reflections of a wind energy pioneer
Sometimes I forget how long I’ve been carrying this dream
of a renewable energy future…
Back in 1976, with my early wages as a newly-minted
electronics engineer, I purchased 30 hectares of very
marginal hill country for $6000 out the back of the Mount
Lofty Ranges behind Adelaide. I had a head full of ideas
about living a self-sufficient existence out there, but it
proved to be too dry and certainly too windy.
At the time I was designing mining instrumentation, and
carried on with that in Australia, Papua-New Guinea and
Canada.
When I had enough money together, I went off hitch-hiking
through Asia, Europe, Canada and North America.
In my rucksack I carried a notebook which I filled up with
drawings of mechanical data loggers that would somehow
be able to measure and record wind speeds and rainfall on
this (now mythical) MEA site, which we called Pine Hut
Knob. [It’s located off Pine Hut Road, and at the time, the
only wind generator operating in the world was on a hill
called Grandpa’s Knob in Vermont USA]. This was in an era
before microcontrollers and personal computers had
arrived, so electronic data loggers for remote monitoring
were yet to come onto the scene in any useful sense.
When I arrived back in
Australia in 1983, thoroughly
fed up with building mining
instrumentation, I worked
on a farm shoveling pig shit
and driving tractors while I
angled for a berth on the
second South Australian
Wind Energy Survey (the
first was conducted by ETSA
in 1953 – the year I was born
- by another engineer named
Les Mullett, who apparently
When that all came to an end in 1987, a single 150kW
Nordex wind turbine was set up near the Coober Pedy
diesel power station. There was no wind, but the Minister
for Mines and Energy of the day figured this turbine would
be very visible to tourists travelling up to Ayers Rock, so he
went against all our advice and went for political points.
This probably set wind power in South Australia back a
decade, as the blades rarely turned (no bloody wind!)
“ ... I worked on a farm shoveling pig shit
and driving tractors ...”
With wind energy monitoring moribund, the fledgling
MEA went off and became involved in monitoring railway
locomotives and level crossings, climate, soil moisture and
literally thousands of other environmental applications
where we cut our teeth in remote measurements. All
that experience stood us in good stead when wind energy
monitoring came back into vogue in the late 1990’s.
Pacific Hydro recently called townsfolk and land owners
together out near Pine Hut Knob to talk to them about
their plans for putting up a wind farm in SA pretty much
where, a decade earlier, I suggested they look.
How many other folk can say they’ve seen a dream come
true? This new wind farm will be visible from the peak at
Pine Hut Knob, where it all began for me and MEA 35 years
ago.
temptation to rush a new product to market, and set it
all up at MEA’s very own wind site at Pine Hut Knob on a
10m mast. There we beat it up for more than four months
in a 7 m/s average wind regime, in the dead of winter
(to test solar charging), and logging data at a one-second
rate to place maximum strain on the telemetry link while
simultaneously testing new sigma-theta and standard
deviation wind algorithms. And yep, the new MEA wind
logger passed all field testings without a hiccup.
150kW Nordex wind energy tubine established at Coober
Pedy in far-north South Australia as a result of the 1984 1987 wind energy survey.
The development of the 4th
generation MEA Wind Logger:
The short version…
MEA has spent nearly 28 years perfecting all the fine detail
needed to reliably collect wind data from remote sites; we
estimate that MEA has logged over two thousand year’s
worth of wind data in Australia and the Oceanic region
during that period, measured on a ‘per-anemometer’
basis.
If you’re really good at something, it looks easy. So others
come along and figure it’s a cinch to do what MEA does;
this is the finest form of flattery. Sadly for them, the devil
is in the detail; we’ve seen off many competitors over the
years when they’ve tried to pull together similar wind
monitoring systems without the benefit of three decades
of hard grind under field conditions.
While the new data logger is visibly different to existing
MEA wind loggers, the high level of integration has a
significant side benefit; production time – and therefore
cost-to-customer – has been reduced by almost a full day.
So MEA wind systems just got less expensive AND more
powerful.
At the most recent wind energy conference in Melbourne in
May 2011, notable for the sense of gloom and uncertainty,
the rabble in the pin-stripe suits, pointy shoes and spiky
hair had disappeared, presumably having moved on to
the mining conferences in a ‘chase-the-money game’ that
favours opportunism over industry loyalty and stability.
Only one old measurement stalwart was present – MEA –
one of the industry’s founding members.
Now we’ve gone the extra mile by spending R&D money to
back our faith in this renewable energy sector.
The development of the 4th
generation MEA Wind Logger:
The long version…
But staying at the top requires continual ‘fine-tuning’ of
products and systems, and MEA’s engineering team has
spent two years quietly lifting our Australian-made wind
measurement systems to a new level well beyond that
offered by imported data loggers.
“... MEA has logged over 2000 years worth
of wind data in Australia ...”
The end-result is an MEA Wind Logger with more
channels than ever before, built-in swappable lightning
protection cartridges, the latest modem USB and packetdata technology, integrated solar/battery systems, quickrelease connectors and SCADA-compatible outputs that
allow us to split signals off and ship them from met-masts
to wind turbines once the site matures. A single-circuit
board at the heart of these systems simplifies production
and lets us build quickly any one of the many wind and
solar monitoring applications that we’ve custom-made
over the years. New metal work allows graded access
to the interior of the logger enclosure under the worst
weather conditions.
Having done all that, we resisted the ever-present
Part 1: Philosophy
Good companies grow organically, continually reinventing
their own product line while they manage human and
financial resources carefully. There are also a couple of
great ways to de-rail a good company, through sloth and
greed.
Sloth is complacently sitting on your bum and stagnating
while technology and customer expectations change
around you, leaving you stranded up some backwater
without a paddle.
Greed is the more insidious version of these two deadly
sins; it is bred from the arrogant expectation that success
in one field will translate into equal success in any related
endeavor combining vertical integration with a grab for
market share. The disciplined creativity that created the
company and its product line is irrationally abandoned,
and a leap into unknown territory is made more hazardous
by not even knowing what one doesn’t know.
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And so here at MEA we steer via the ‘long view’, plus a
pretty deep understanding of what our core strengths
are, about one hundred years of combined engineering
experience in environmental measurements, and a solid
understanding of what parts of the wind business are NOT
ours and that we must hire in…
In the wind energy monitoring business for example, we
know we can build the instrumentation, software and
telemetry systems that have powered over 300 wind
monitoring sites over many decades. We also know that
we are NOT in the wind mast manufacturing business.
Nor do we have riggers on the MEA staff to erect these
towers and to get the instrumentation aloft. To that end
we form partnerships with those companies who make
those aspects of wind monitoring their core business. The
upstream phases we don’t do either; data analysis, wind
site modeling, negotiating with land holders, civil and
electrical engineering works and so forth.
programs written in Basic for a DOS operating system.
There was no telemetry, no portable computers, no
Internet, no solar power systems, no data display, no
cellular phones. Logger memory was a miniscule 8kB. Data
was collected by swapping loggers over in the field with
help from local farmers, station masters, aboriginal
community officers and land owners. All data analysis
software had to be coded in Basic to apply calibrations,
generate printed reports and create histograms.
MEA simply brings the whole wind measurement system
together and gets data flowing back to a customers’ desktop.
MEA is then just a thin layer in this renewable energy
sandwich, and the whole stack relies on our expertise in
producing ‘hole-free’ bankable wind data.
The case study that follows is the story of the development
of the fourth generation of MEA wind loggers; why we did
it, how we did it, and how it all turned out. We’ve put
much of the technical stuff into layman’s language to
make it readable.
“... here at MEA we steer via the ‘long
view’ and a deep understanding of our core
strengths ...”
There’s not too much to be found here about the project
financing. Suffice to say that the small profits gleaned
from earlier MEA wind system sales have been ploughed
back into the product development process to keep this
all-Australian technology up there at the sharp edge of
competitiveness and utility. There are still no BMW’s in the
MEA company car-park: Joe and Andrew continue to walk
to work and live frugally so that the MEA itself may live on
for many more years.
And down in the MEA engine-room, the 5th generation
MEA wind systems are already on the drawing board. But
that’s a story for another day…
Part 2: A short history of MEA wind logging
systems – Generations 1 to 3
MEA first generation wind loggers were built in 1984 for
the South Australian Wind Energy Program (1984-1987).
Thirty sites across South Australia were instrumented in
both coastal and remote areas.
Back then ‘PCs’ (personal computers) were new, ran at 4.7
MHz, had monochrome screens, floppy disc drives (no hard
drives), noisy dot-matrix printers, no graphics, and
Loggers had no programmable instruction sets, but instead
used customized commands created for the wind industry.
Anemometry consisted of combined wind speed/wind
direction sensors from VDO in Germany and were largely
used by yachtsmen at the mast head. Calibrations were
carried out at the local university in a wind tunnel calibrated
against pitot tubes and sloping manometers. Masts were
9m Hills Industries three-section guyed telescopic masts
that could be collapsed down and carried on the roof-rack
of the Toyota Land Cruisers used to deploy the equipment.
MEA second generation wind loggers went into the field
over a decade later. Not because we were slow to develop
the technology, but simply because the wind monitoring
business had collapsed after the token study carried out
by ETSA and the SA Department of Mines and Energy was
completed.
By this time (in the late 1990’s) MEA had diversified into all
sorts of general data logging activities to survive. These
applications included monitoring on freight locomotives, in
remote diesel power stations, at electricity sub-stations,
and all sorts of climate and soil moisture applications, to
name but a few.
“There was no telemetry, no portable
computers, no Internet ...”
By now we had a new generation of data loggers that
were more generally programmable, DOS had given way
to Windows operating systems, telemetry had advanced
from copper land lines to analog phones to GSM to CDMA
cellular wireless networks, and MEA had spent serious
development money (for such a small company) to develop
Magpie software to handle all these functions.
We had tested about a dozen anemometers but were
finding the Climatronics wind speed and direction clusters
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that we’d settled on and adapted were failing way too
soon at exposed coastal wind sites subject to salt-laden
winds. The American manufacturer claimed that no-one
else had reported failures and therefore accepted no
responsibility; a common tale heard over many years that
we came to understand was the hallmark of a poor supplier.
data at ever higher baud rates. We discovered high-gain
antennas which allowed us to get to remote wind sites to
collect data economically and reliably. These multi-user
data systems allowed MEA’s technical staff to access remote
systems without having to leave Adelaide, diagnose and
repair faults, or to recommend actions to resolve issues.
We became experts at diagnosing problems without taking
our feet off the desktop.
“... data capture rates headed above the
99.0% mark.”
Early towers - 10m, then 30m, then 50m, then...
Tubular towers imported from Wales and the USA were
beginning to be replaced by Australian-made products,
and early surveying 10m towers were giving way to 50m
tubular ‘tilt-up’ towers.
MEA third generation wind loggers moved to more memory,
more channels, 16-bit differential measurements to cope
with long cable runs, high gain channels to handle solar
thermopile instruments, bigger displays, more counter
channels for more anemometers. We had sorted out
temperature-compensated three-stage solar charging of
sealed lead-acid batteries so that they’d last at least a
decade under field conditions.
The big change in data handling came with the advent of
the Internet and packet-data facilities on new cellular
phone modems; we spent another two years of product
development time to create a ‘packet data terminal’ or
PDT that would automatically push data offsite to a remote
Internet-connected ftp server that Magpie software could
access to get data to desktops in a wired world. Now we
had ‘tera-byte’ logging capability, and two layers of data
buffering between the measurement and the final
database. Wind farmers heading off on annual leave need
no longer organize someone to take care of data unloading
for them; the MEA PDT ‘robot’ kept on pushing up near
real-time data every few hours. Data had less ‘holes’ in it
due to user errors. If the Internet or cell phone links went
down, data backed up safely in the logger or ftp server and
made its way home once the connection was restored.
MEA data capture rates in our wind systems headed above
the 99.0% mark.
A long evolutionary process had sorted out how to protect
all this gear on tall metal towers on exposed peaks from
the lightning strikes that returned again and again to these
favourite spots. Tilt-up towers had peaked at about 60m,
and climbable lattice masts heading up to 100 m were
taking their place. More instrument layers were added,
and we were able to use the high-speed serial buses on the
new loggers to expand counter channels to 8 or 12.
MEA’s Packet Data Terminal automatically
unloads the data logger & pushes the data to an
FTP server.
Magpie software for wind systems sported new Wind Rose
software and multi-site data comparison in graphical
format. The big change was the introduction of stable
Next-G cellular phone telemetry in Australia, and modems
registered on these networks were capable of moving
Cable damage and data loss due to cockatoos chewing
PVC cable jackets was overcome with the introduction
of flexible steel cable conduit. We developed special
equipment for threading multi-core cables through 100m
lengths of this conduit. Coated-steel logger enclosures were
still not holding up at coastal sites and were rusting out;
these were replaced by more expensive but more durable
stainless steel enclosures, and we found that we could
have them specially pre-punched to speed production.
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We also invented novel methods of laser-alignment to
ensure that wind vanes were accurately lined-up on sensor
cross-arms.
Mast-head junction boxes, un-pluggable sensors and much
tinkering with cross-arm hardware allowed riggers hanging
off towers to manage system installation and maintenance
much more efficiently. We worked closely with the
riggers and tower installers to make sure everything came
together and was working perfectly before we left site.
We sent MEA techs to site to commission each system, as
this was beyond the technical capabilities of the riggers
who had put the tower up.
period, logging several thousand years of wind data on a
‘per anemometer’ basis.
You can’t hurry experience!
Barometric sensor technology stabilized, temperature
and humidity sensors improved, sensor shelters became
smaller and we learnt how to match air temperature
sensors to better than 0.1°C to measure air mass stability
over the tower height.
But the big change came with better anemometry out of
Denmark’s national research institute, Risœ. These
anemometers had an impeccable pedigree, scientific
credibility and MEASNET bankable calibrations performed
in European wind tunnels. They satisfied the grumblings of
even the most fastidious and skeptical banker’s engineers.
We learnt about international standards, and changed
cross-arm designs to avoid any tower-induced turbulence
and to get cup sets into the free air stream. We found a
Welsh wind vane of comparable quality and added it to our
stable of sensors.
From a production sense, however, we were still
manufacturing systems that relied on solid point-to-point
wiring and all sorts of modules that had been gathered
together to answer customer needs as those demands
grew and varied.
The 4th generation of MEA wind loggers needed to make
an incremental development in our in-house production
efficiencies, to include the latest modem and lightning
protection technologies, to speed up installation and field
servicing, and to cut the cost of production at a time
when a maturing wind industry was again on the ropes as
Government policy wavered in the wind.
Wind folk were beginning to think more about cutting
costs now that reliability had maxed out.
So our next chapter tells the story of how MEA’s R&D team
took up the challenges of getting all the latest technology
delivered at a better cost – our 4th generation MEA wind
logger.
This work began in early 2010, with four months of field
testing completed in July 2011. Production units became
available in August 2011. Estimated cost of the project was
somewhere north of A$100 000.
Back at base, we discovered that under certain conditions,
standard deviation of wind speed and sigma-theta of wind
direction measurements exhibited tiny errors that were
none-the-less annoying to our more meticulous customers.
Much high-speed wind logging followed at MEA’s wind
site at Pine Hut Knob, and at various customer sites.
Spreadsheets piled up, and both problems were identified
as stemming from the precision of the algorithms involved
in the calculations, which were of themselves correct. So
we fixed all that.
So why a fourth generation of MEA wind logger?
Technically then, MEA wind systems had evolved by the
third generation to deliver bankable data from remote
wind sites with almost absolute reliability. Almost 300
wind sites had been installed by this stage over a 25 year
“... the big change came with better
anemometry out of Denmark’s national
research institute ...”
Part 3: The Technology
Three major things and a bunch of minor things drove us to
improve the MEA wind loggers by yet another generational
change.
Printed not wired circuits!
Big Deal #1, the big no-brainer in the room, was to replace
wiring looms with printed circuitry and to consolidate all
the small pieces of circuitry onto a single PCB that would
be made by the robots down at the circuit board factory.
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This would neaten everything up and cut a day or more out
of our production cycle.
And what were all these bits?
Just stuff that evolutionary forces had added to our wind
loggers over more than 25 years - chargers, terminal
blocks, lightning protection units, signal conditioners,
extra counter channels, modems, PDTs, communications
ports, switched power supplies, fuses, switches etc. etc.
etc.
ports to the appropriate channel on PDT+ modem, while
allowing for the horrible likelihood that we might one day
need to get data out of a site so remote that only satellite
communications would do the trick.
“So we turned out some elegant circuitry ...”
SCADA interfaces
Big Deal #3 was the ever-present dual-purpose nature of a
wind monitoring tower. Some folk want the meteorological
data to be shared in the future from the met mast to other
on-site recording (SCADA) systems once an actual wind farm
is installed. The very low-power nature of solar-powered
monitoring systems makes this interface problematic, so
MEA’s engineers needed to solve this one ‘right here right
now’ so we wouldn’t get caught napping somewhere down
the track.
So we turned out some elegant circuitry and created
signal splitting technologies and current-loop generators
to allow up to 7 anemometers and 7 analog sensors (wind
direction, temperature, humidity, barometric pressure)
to be tapped off the polled sensor circuits and shipped
off over hundreds of meters of multi-core cable to some
future wind turbine logging system.
New modem technology
Big Deal #2 was driven by the upcoming obsolescence
of our standard Next G modem and the need to shift to
the more compact and less expensive style of ‘built-in’
modems. This sounds grand and easy, but bogged us down
for three months as we tore our hair out while trialling
three different modems from around the globe in a shootout for fitness and readable documentation. OK, the
Chinese one turned out to be inscrutable, the German
one was too clunky, so we settled on an American/French
model with good technical support right here in Australia.
Then the damned things wouldn’t work with our packet
data terminal (PDT); it had worked perfectly fine with
the modem that preceded it. Our chosen modem kept
hanging up on us right after the first call, exactly like all
those young maidens all those years ago dropping the line
when Andrew called them up to ask for a date. As always,
there turned out to be an inscrutable trick to it which
we stumbled across in a chat room frequented by other
nerds like us struggling with similarly weird problems. So
we got our PDT to say the magic line we’d discovered to
the modem, and we were through. The project went from
being dead in the water to back on track within the space
of half an hour!
“Then the damned things wouldn’t work ...”
Of course, that wasn’t the end of it all – the new modem’s
power supply proved to be finicky, we found we needed to
add yet another USB port to be able to program the modem
if its head blew up under field conditions, we needed to
physically shield all this sensitive circuitry from possible
condensation out on remote hillsides, and we had to
steer communications from both USB and RS232 computer
All this at no cost, of course, so we needed to create
plug-in interface circuits that would only get plugged in if
needed, rather than lump every customer with stuff they
might never need.
OK, then we were ready to sort out all the minor things…
Squads of anemometers
For all those of you who think that more than three
anemometers is self-aggrandizement, you’ve never had to
festoon a 100m met mast to study terrain-induced wind
shear at high logging rates where giga-bytes of wind data
tracking every gust and lull must be logged and pumped
off-site for in-depth analysis. So our new wind logger comes
fitted out ready for at least eight anemometers and all
the usual wind vanes, barometric pressure, temperature,
humidity and solar sensors. We could do this via special
counter circuitry that makes use of our logger’s special
serial buses to import external data.
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Lightning protection
Is there more?
Lightning protection is a big deal in wind systems, and
lightning strike (either direct or nearby) is the single
greatest cause of data loss.
Yes, there’s plenty of little extra touches that went into
the 4th Generation MEA wind logger, but they’re pretty
boring and so won’t get a mention here.
Fortunately, once you’ve got all your sensors, logger and
modem prophylactically protected in such a way that all
that horrible high-voltage high-current electrical energy
is shunted safely to ground there’s only more thing to
remember; that the price of this protection is the selfsacrifice of the protection device itself. They die to
protect their friends. One has then to harden ones heart
and ditch the corpse for another unblooded lightning
protection unit. So we built in plenty of multi-channel
PCB-mounting swappable LP cartridges so that even the
local land-owner can service an MEA wind logger without
any training whatsoever. Our systems come back on-line in
minutes with the most unskilled labour!
Someday one of these little touches will kick in and save
our bacon without our knowing it.
“... the price of this protection is the selfsacrifice of the device. They die to protect
their friends.”
Quick-release wiring
If your business is environmental measurements, then you
have to dream up the worst-case service scenarios and
design for them, all based on Murphy’s Law #36, that
‘Mother Nature is a Bitch’.
To this end, we had to recognize the possibility of
catastrophic failure of the whole of the field wiring and
communication systems, and design some serviceability
into the product for the sake of our own staff.
In fact nobody will know, except that MEA’s reputation
as Australia’s reliable wind logging company will remain
intact, our staff will keep their jobs, the directors’ can
sleep easily each night and Australian engineers will have
made some small contribution to Australia’s renewable
energy future.
That will be something to be proud of as we sit in our
rocking chairs on the verandah of the Old Folks Home,
looking back…
Acknowledgements: fourth generation
MEA wind logger R&D team
Project leader and
mechanical engineering:
Jack Hoogland
PCB layout, testing and
design-for-production:
Christian Bischoff
Modem qualification and
PDT interface coding :
Raffaele Iacobelli
Electronic and
system design:
Andrew Skinner
The reason for this imperative is that good wind sites are
very unpleasant places. Therefore one can only service
systems at a fairly crude level; we call this working method
‘pulling the guts out’. This needs to be done swiftly before
our techs die of exposure. So all that field wiring of a dozen
or more sensors and solar panels has to be ripped off the
burnt board, a new system plugged in, and the wiring
plugged back together with no possibility of mistakes.
To this end, we found ‘unpluggable terminal blocks’ that
could be uniquely ‘keyed’ so that pushing the right socket
into the wrong hole just wasn’t going to happen.
New wind logger enclosures
We also needed to prevent the wind logger innards
drowning in ‘horizontal rain’ while all this service work
was going on.
So Jack, our mechanical engineer, came up with a brand
new customized three-layer enclosure design that allowed
one level of access to casual visitors, a second keyed
access to the lightning protection cartidges behind the
scenes, and finally, a third level of access to the electronics
themselves.
And yes - it’s all stainless-steel, because nothing else
survives under high wind conditions where either salt or
sand is blowing…
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