According to SBI Research, the market for smart grid enabling technologies (including two-way wireless communications) in the United States is currently about $6.4 billion.

This market is expected to grow at 20.8 percent annually through 2014, when the smart grid enabling technology market will be about $16.5 billion. The bulk of this market will go toward smart sensors and devices which will need to be placed throughout the grid and within consumer homes and office buildings.

via Smart Grid.