The KØNR Radio Site

BPL Update

Bob Witte KØNR
Technical Coordinator
ARRL Colorado Section
Tel. 719 488-0859
 

You've probably heard about Broadband over Power Line, commonly known as BPL. This technology uses an electric utility's power lines to deliver broadband Internet to its customers. Sounds pretty good until you understand how many of these systems cause interference to the ham bands. This is an update on what is happening around the nation and in Colorado concerning BPL.

Xcel Energy BPL in Boulder

Xcel Energy has announced plans to make Boulder the first SmartGridCity™ in the nation. The pitch from Xcel is:

The next-generation electricity grid will allow our company to better meet growing demands, address environmental challenges, maximize available resources and optimize the entire energy system. Ultimately, a “smarter” grid helps us serve our customers by creating more options for managing personal energy use, habits and cost.

BPL has caused quite a bit of concern in the amateur radio community due to its use of HF spectrum for data communications via powerline. Some BPL deployments have resulted in considerable interference to licensed amateur radio operators.

Xcel has posted quite a bit of information on their Smart Grid approach on their website. The good news for ham radio operators is that Xcel is using BPL technology from the Current Group. This implementation of BPL is considered "ham friendly" since there have been multiple deployments of this flavor of BPL that have resulted in no radio interference complaints from the ham community. This could be just luck, but there are technical reasons that indicate Current may have a system that doesn't interfere with most ham frequencies. The key attributes of the Current BPL system are that the Medium Voltage Lines use 30 to 50 MHz (outside the ham bands) and the Low Voltage Lines use 4 to 21 MHz notched for the ham bands using the Homeplug standard.

The radio amateurs in the Boulder area have been monitoring the ham bands for interference and there have been no complaints. It seems that the notching of the ham bands is working to an acceptable level. Interference to general shortwave broadcasting is noticeable.