By Jessica Binns
Before a wind farm can be
established, extensive research must be conducted to ensure that enough power
will be generated to justify developing the property. The process involves
installing 200-foot-tall meteorological towers that measure such data as wind
speed, direction and temperature. For Renewable Energy Systems, headquartered
in Kings Langley, England, this information was captured on data cards through
wireline dial-up modems attached to the towers, a process that Dr. Andrew
Oliver, VP of technology, describes as a "real administrative burden."
RES did not employ a team of field
technicians to retrieve the data cards. Instead, it would establish a relationship
with someone who either owned the property where the test site was located or
simply took interest in the project, and pay the individual to trek out to the
remote location once a month to collect and mail back the data cards to RES'
regional research offices.
"Sometimes our contact would send
the data card back to us promptly, and sometimes they'd forget to send it right
away," says Oliver. "Sometimes the card would get corrupted, or it would get
lost in the mail. In truth, we wanted to maintain the card system but gather
data more frequently, so that if a wind tower was zapped by lightning we
wouldn't lose a month's worth of data."
When the stresses of not being able
to analyze wind data in a timely manner got to be too much, RES began to research
wireless solution options and discovered the Raven, a powerful wireless modem
offered by AirLink Communications of Hayward, Calif., which was acquired
earlier this year by Sierra Wireless of Vancouver. Featuring AirLink Embedded
Operating System (ALEOS), packet-level diagnostics, over-the-air firmware
updates, and remote monitoring and configuration capabilities, the Raven was a
considerable improvement. With the wireless modem, RES can now instantly tweak
settings, remotely reset a device that has been knocked offline, perform
onboard diagnostics and monitor the performance of the carrier network.
With more than 800 turbines in the
alone, producing in excess of 1,100 megawatts each year, RES is a leader in
harnessing wind energy. The company has helped governments and utilities, among
other industries, develop this sustainable and financially attractive energy
solution and unobtrusively integrate wind farms into the surrounding
environment. RES also controls the single largest wind farm in the world, a
sprawling site located in King
state better known for its oil production.
Setting up the new wireless system
proved to be a challenge. RES contacted AirLink partner Mobile Electron, an M2M
and wireless data systems integration consulting company, headquartered in
Lutz, Fla., for help with configuring the solution. David Schwarz, senior VP of
Mobile Electron, says his team recommended the line of Raven modems because
each one is tailored to different cellular carrier technologies, such as GSM,
CDMA, GPRS and EDGE.
"A lot of times when we start to
analyze a customer's requirement, it almost becomes a real estate analogy:
location, location, location," says Schwarz. "We initially tried to deploy the
appropriate Raven modem in the area where any given carrier might have the
preferred, prevailing service footprint, which is critical to the end-to-end
solution." The wireless modem system is an IP-based solution, says Schwarz, and
has greatly improved the transmission of data to RES regional offices. What's
more, RES can be notified of problems with the meteorological towers much more
quickly than before.
RES collects wind data by using a
Campbell Scientific data logger attached to each tower. The system is set up to
retrieve historical data on demand; workers send a query from their office
computers to the data logger via the Raven modem, which is assigned a static IP
address. "This company that is on the forefront of sustainable energy
completely utilizes M2M technology to accomplish what could be a time-consuming
process," says Schwarz. "There is a dramatic impact on the productivity of
personnel. Running a wireline out to these remote sites could take six months
and cost a lot of money. And if the site doesn't prove suitable for wind
farming, RES can just pack up and go--there's no infrastructure involved."
There were significant drawbacks to
not having robust data under the dial-up modem system. "Losing a month's worth
of information adds to the uncertainty of how much wind production there would
be at the site," Oliver says. "Bottom line, it comes down to what the banks are
willing to lend you. If there's more uncertainty, they'll lend you less."
Beyond the unreliability of
collecting the data cards, the dial-up modems themselves were not economical in
terms of power consumption. The old modems utilized solar batteries and were
run in a circuit switch, which meant that RES offices could not connect to
multiple modems at one time. "We'd have a window of time when the remote
systems would shut off so as to not drain the power supply," Oliver says.
"Sometimes the modems would search for a signal for hours."
The cost savings from the AirLink
solution include reduced long-distance phone bills, since the new modems are
wireless, says Oliver, and the elimination of expenses related to the freelance
technicians who previously retrieved and mailed in the data cards. But the
payoffs, such as "reduced operational inefficiencies," are more significant.
"We can be more proactive in our
business," Oliver explains. "Someone came in the other day and said, 'I'd like
to know [how much energy] a wind farm would have produced today.' It was the
hottest day of the year in .
[The client] wanted to know by 8 a.m. the next morning, and we were able to tell
him. There's no way we could have done that before. We wouldn't have been able
to get the data cards back to the office in time."
Finding a solution that was also
environmentally friendly is especially satisfying. "Many times you find the
alternative communications capability of a wireless network and these types of
modem solutions are preferred in that they are noninvasive," says Schwarz.
"RES, in analyzing locations for proposed wind farms, and in monitoring wind on
test sites, is looking to do as little damage and disruption as possible to the
surrounding property. The modems run off DC power, solar panels and
rechargeable battery packs."
RES has more than 60 test sites in
and roughly 48 have been transitioned to the AirLink solution. Retroactively
outfitting the towers with the new modems is a relatively simple process that
takes a few minutes, says Oliver. If a technician needed to visit a test site,
the Raven modem was installed during that trip. Today, all new sites are built
with the Raven modems, and all previous tower installations that can be
retrofitted have been.
Because many of RES' test sites are
so remote and characterized by difficult terrain, some cannot be transitioned
to the AirLink solution. "To the extent that we can use the wireless modems, we
are," says Oliver. He admits that lightning can still damage the Raven, just
like the old dial-up modems; but the difference now is that RES will have
received all of the data prior to the weather event instead losing 30 days of
RES currently maintains 15 percent
wind energy market share and hopes to increase that number to 20 percent. With
streamlined data collection operations, thanks to AirLink's Raven wireless
modem, that goal is closer than ever. //