Wind output to grid gets key upgrade
By Tux Turkel, Staff Writer | www.pressherald.com
Wind farms have been second-class citizens in New England’s power system.
Because their output is dictated by how hard the wind is blowing, and because most wind farms are located in remote areas with small transmission lines, their ability to get on the system has been limited.
If there was a risk that a wind farm might produce more power than local transmission lines could handle, the system operators at ISO New England had to manually call each wind farm and ask it to reduce output.
This was a complicated and time-consuming process in shifting wind conditions. Operators tended to be conservative and curtail output sooner, or by larger amounts, than might otherwise be needed.
Now that’s changing. It’s part of an effort to integrate weather-dependent renewable energy sources into New England’s power grid.
The 21 major wind farms in New England have a capacity to generate 970 megawatts. Based on the average amount of time the wind blows, they can serve 237,000 homes a year. Fourteen of the wind farms are in Maine, with a capacity of 602 megawatts.
As of last month, wind farms and small, intermittent hydro-electric dams have begun getting automatic, electronic dispatch instructions every five minutes from ISO New England.
ISO New England also gets wind and weather data from each farm. It’s fed into a forecast that’s constantly being updated by a company in Europe.
The forecasts have proven to be very accurate, which give the wind farms and system operators a good sense of how much power can be produced. That information lets the ISO set a ceiling for each farm’s output, a top end that can be changed continually so that turbines can produce as much power as possible, without the risk of overloading transmission lines.
The automatic system also lets wind farms compete on price with other generators to sell energy into the wholesale market.
URL to article: https://www.wind-watch.org/news/2016/07/07/wind-output-%e2%80%a8to-grid-gets-key-upgrade/