During July of 2009, I predicted I would have problem with radio/electro-magnetic interference using the HES EnergyNet Internet service.
However, Energynet will suffer from the same faults of a crowded 2.4 Ghz band that includes routers, wireless phone handsets, and microwave ovens.
This is definitely true for microwave ovens. The wireless is completely unusable while the microwave is running. Recently, the room where all of the computer equipment is, was re-arranged with two major changes related to the networking setup. The first being the removal of two big CRT monitors from the room and the second is that the EnergyNet box is now plugged into an uninterruptible power supply. I noticed over the next several days that Internet speeds were dramatically better. Before the re-organization data transfers averaged ~400 kilobits/second. Which is far less than the advertised 3 megabits. After seeing the difference in speed after making these changes I got curious and plugged the Energynet box directly into the wall like it was before. Internet speeds worsened at the same time.
Based on this anecdotal evidence, I would recommend using a battery backup to power the EnergyNet router. The UPS serves to isolate connected devices from fluctuations in mains power. At least in this instance it does an excellent job.
I would be interested to know whether other customers have experienced the same symptoms. Overall, I like the service from EnergyNet but other people considering buying it should realize the equipment is very sensitive to interference. Another thing about my setup is that I use a wireless router of my own to re-transmit the signal to my laptop. So if there is any interference in the air I get it both coming and going.