Skip to Content
MIT Technology Review

  • Qixin Chen


    PROBLEM: Many power plants connected to the grid operate well below their full capacity, wasting fuel. If we have no means to store large amounts of electricity or reliably predict power demand, however, maintaining idle capacity is the only way to respond quickly to surges in demand. The problem is particularly challenging in China, a huge consumer of electricity. Its push to add thousands of wind turbines, with their variable, difficult-to-predict output, will make it even harder to efficiently balance supply and demand.

    SOLUTION: Software from electrical engineer Qixin Chen of Tsinghua University in China accurately forecasts power demand and helps utilities coördinate power plants. His software is already in use in nearly 200 cities and 10 provinces in China. One province, he says, reported saving $30 million and 240,000 tons of coal in a single year.

    Chen found two ways to improve on existing demand-forecasting software. First, he designed the system to better choose the right forecasting approach for particular areas; differences in demand and weather patterns mean that some techniques are much better suited to some locations than others. Then he enabled his system to analyze its own previous prediction errors and adjust its formulas so as to minimize the errors the next time similar conditions occur. The resulting demand forecasts are reliable a month ahead. Other forecasting systems, in contrast, aren’t sufficiently accurate beyond a day or two, if that.

    The results are helping utilities dole out electricity more efficiently. Now Chen is working to adapt his forecasting software to predict the power output of wind turbines. His system would take into account wind data gathered for miles around the turbines, providing a sharper picture of which wind shifts are likely to affect them in the coming hours. That means utilities can know when to expect more power from the turbines so they can cut back on conventional power generation.

    Kevin Bullis