February 2008

Web Exclusive

Clear view of wind power

OPC technology helps generate operational advantages for turbine farms

Fast forward

  • Data from different turbine systems did not offer apples to apples comparisons.
  • OPC technology allowed for performance comparisons at all winds parks.
  • Multiple levels of communication brought in more efficiency and productivity.
By Greg Howard and Pablo Asiron

AES Wind Generation is a company working on leading edge energy issues, but facing old world technology problems.

There is no doubt wind energy is quickly becoming a source of renewable energy, which will allow for a reduction in the dependence on fossil-fuel that create carbon emissions. While wind-power generation has its own technical considerations, the central challenge faced by a large-scale wind-farm operator is the same as faced by conventional utilities: getting data from disparate, geographically dispersed sources to the people that need it, when they need it, in a form they can use.

A wind-power developer, owner, and service company, AES manages 17 different wind farms across the U.S., five of which comprise more than 500 turbines, with a total generating capacity of over 700 MW, which is enough energy to fulfill the electricity needs of 200,000 homes. There are six different turbine models, from four different manufacturers, in the AES fleet, representing 20 years of wind turbine evolution, SCADA system development, and data formats.

This is in an environment where each manufacturer's turbines present a different data set driven through different SCADA systems. From that flow of disparate data, not only do basic measurements such as production and power factor need to be taken, but also analysis data such as temperatures, pressures, response times, and fault indicators.

Historically, AES gathered the data by going through individual manufacturers' data-access systems. Rather than having a web-based system that allowed the company to go and see values and data for all the different models, types, marks, and areas, AES had to go into individual systems to look at data.

These barriers to data access were potential barriers to optimal marketplace performance. It became very difficult to have the operators logging into six SCADA systems to evaluate the electrical status of a park when the power purchaser is demanding instant decisions.

In order to get the most from their technically disparate and geographically dispersed fleet of turbines, along with the megawatts of assets on which they hold third-party service contracts, AES knew they had to bring all the data into a system that allowed them to compare wind parks, evaluate turbine performance, perform analysis of problems, and maximize the output of individual turbines.


When analyzing data yields results, why not see if the same concept applies on other locations. If you look at turbines in Wyoming a certain way and get good results, why not see if you can do the same thing in Palm Springs?

Decision time

After realizing they were losing out on efficiencies and on productivity, AES sat down and came up with requirements for a data access and visualization program:

  • It needed to be universally accessible by employees, regardless of location, without installing software on each employee's computer.
  • It needed to be able to access data from legacy systems, along with new wind farms that will be coming on line.
  • It needed to bring enough data together in a single screen to allow for operational decisions even when the data was coming from three different substations with three different manufacturers' SCADA systems.

After evaluating all their options, AES decided on a system using OPC technology for real-time and historical data access.

Based on open standards, OPC technology allows access to data from disparate sources without requiring specific, proprietary software or hardware for each data standard. AES also chose a historian for its store-at-the-source data handling capability.

Combined with a web-based data visualization product that connects real-time, historical, and relational data sources to trend, chart, monitor, report, and display, OPC allowed AES to eliminate multiple SCADA systems and make their fleet data universally available to anyone, anywhere.

This system ended up fulfilling AES' requirements for data distribution. Now AES' auxiliary services also want access to the system.

These multiple levels of communication-not only of information, but of ways of looking at that data-bring in more efficiencies and add to productivity.

The biggest issue with wind generation is there is nothing really steady-state about it. You constantly have to overcome all the different variables to try to get something that gives you an apples-to-apples comparison of turbines inside a fleet and between fleets.

The new software makes it easy for users to share the information from any location. When a new way of analyzing data yields results, why not see if that concept applies on other locations. If we are looking at the turbines in Wyoming a certain way and getting results, why not see if you can do the same thing in Palm Springs?


Before the system was up and running, the software showed its potential.

When the team was building the monitoring screens for the Texas substations, it put a screen together so you could see all the Texas substations, and that was the first time they had been able to get a collective view like that. While they were wrapping up the installation, one of the wind farms' breakers came back as open. They quickly went and checked their installation to see if they made an error.

After they completed some diagnostics with some other data systems, they found out, in fact, the farms' breakers were open. They called the local support staff at home in bed and had them get out to the farm to fix the problem. It turned out a snake had crawled up into an electrical setup and shorted out the park. How long would it have taken them to notice it? They would have noticed it eventually, but having these screens that are so encompassing it is easy to pick out operation-critical factors in a short period of time.

AES is going to continue to internally develop content to share designed by its users, rather than using third parties. That will ensure the delivery of data in the ways the company understands.

AES is now living in a new technology world where they are learning to share and get the information to where it is accessible and easy to get to.


Greg Howard is a project information manager at AES Wind Generation Inc., and Pablo Asiron is a product manager at Matrikon.