The widespread underperformance of wind projects is generating interest in better measurement and forecasting technologies at the front end of development. Can these same devices provide a new value stream in the form of near real-time wind forecasts? Power trading desks at firms that manage actual physical assets, both wind generation as well as other forms of power generation may benefit the most.

Tools capable of generating accurate 10 to 20 minute in advance forecasts of wind power have also not been widely available until recently. For the most part, meteorological towers have been deployed to help site wind farms on the front end of the development path or at the back end of operations to optimize production. Federal Aviation Administration (FAA) regulations render so-called “met towers” over 80 meters in height as problematic due to regulatory show stoppers. As a result, there is growing interest in two new emerging technologies now being deployed to collect more accurate data at heights (140-200 meters) where today’s multi-megawatt (MW) wind turbines actually capture the kinetic energy of the wind. These two technologies are sonic detection and ranging (sodar) and laser imaging detection and ranging (lidar) devices.

Both sodar and lidar have the advantage of being ground-mount systems whose data can be cross-correlated with data from met towers. Sodar devices are typically double the cost of a met tower ($50,000 versus $25,000), while lidar costs can reach as high as $200,000 or even $250,000 per device. Sodar can run on a small solar PV systems augmented, if necessary, by a small fuel cell. Lidar is far more energy intensive, often requiring dirty diesel generators, but is more accurate up to 200 meters. Sodar technologies can also measure up to these heights, provided potential interference issues are mitigated or accounted for.

At present, leading engineering analysts working on behalf of banks and financial institutions do not accept a sole reliance upon sodar data. However, this will change as the technology gains a bigger market share and is proven and validated by a third party analysis of sodar data with actual past performance of wind farms. A recent study commissioned by NREL and released in June 2010 found that Triton’s sodar wind resource measurements at a Texas wind farm correlated well with data generated by a nearby 80-foot met tower. “We see Triton as a valid, stand-alone system for wind measurement studies,” said Dennis Elliot, principal scientist with NREL. “In addition, Triton was reliable, with an uptime of over 98 percent.”

Ironically, the main advantage of real-time wind data may not be when the wind dies down but rather when the wind speed increases to the point that the turbines have to shut-down. In this case, the entire wind farm would be producing at maximum capacity, and then rather suddenly come to a complete halt, potentially creating a nightmare for grid operators (see below).

By 2015, the costs of real-time forecasting should come down to the point of allowing broad networks of sensors to increase accuracy at a competitive price. The going rate for wind forecasting services at present is $2,500 per month per wind farm. At that rate, the current wind forecasting market in the U.S. represents roughly a $20 million annual investment. Yet that figure should escalate significantly as wind capacity continues to grow and the value of real-time wind resource data also increases as MISO, ERCOT, NYISO and other control areas look to integrate wind more directly into scheduling protocols.

Globally, wind forecasting market may be as large as a $100 million annual enterprise, but given the diversity of market designs, there is considerable uncertainty. It is safe to say that this global market will grow in lockstep with future wind capacity additions, which grew at a 31 percent annual rate in 2009.

Peter Asmus is a renewable-energy analyst for Pike Research.