"Smart" Meters - published in the Sun August 11, 2011

Aldo Salinas, a supervisor with Texas Meter and Device,

 is in charge of installing smart meters in Georgetown

A controversy about “smart” electric meters is raging through the internet.  Some say the meters are exposing us to dangerous radiation; others believe the meters are prying into our private affairs.  The city of Georgetown is currently in the process of installing new meters that measure the amount of electricity used by a home in 15 minute intervals.  The data is stored, and then several times a day the information is sent wirelessly to the utility company, as if the meter were sending a text message.  This transmission is the crux of the concern.

The truth is that Georgetown residents have already been using meters with wireless technology since 1998.  The old meters transmitted only once a day, but the wholesale market for electricity operates on a 15 minute standard, so the old meters were obsolete, and they were wearing out anyway.

Currently customers pay the same price for electricity no matter what time of day it is consumed, but at some future date the new meters could be used for time-of-use pricing, offering customers the option to pay lower rates for electricity during off-peak hours.  For example, rather than running the dishwasher at 6:30 pm when demand is high, it could be run at 11 pm for discounted rates.  This shift would not only save customers money, but would allow the city to avoid buying expensive electricity during periods of high demand.

The smart meters are clearly useful from an energy standpoint.  What about possible health effects?

Human beings have always lived in a soup of electromagnetic energy from the sun, coming at us in a broad spectrum of wavelengths and frequencies.  We are most familiar with the center of the spectrum, visible light, because that is the frequency our eyes evolved to receive.  Higher frequency energy, like X-ray, carries more energy than visible light.  Because X-rays have a very short wavelength, they can penetrate all the way through your body to make a picture, but you can’t feel anything at all because you have no sensory receptors for X-rays.  X-rays are called “ionizing” radiation because their extremely high energy enables them to knock electrons off molecules in DNA, which can lead to mutations and even cancer.

In contrast, microwaves and radio waves are less energetic than visible light.  These waves are called “non-ionizing” radiation because they are too weak to knock electrons off DNA molecules.  They can however cause vibration of molecules in biologic tissue.  A microwave oven uses a 2450 megahertz signal to vibrate water molecules in food, heating it up.  This is called thermal effect.  Radio waves are even lower frequency than microwaves, but thermal effect has caused serious burns in workers or military personnel who stood directly in front of a powerful radar antenna for a prolonged time.  Sailors used to believe that the thermal effect from radar could make them infertile for 24 hours.  Unfortunately for women on shore, this method of contraception did not prove to be reliable.

Just as sound waves can be loud or soft, radio signals can be generated with differing power densities.  The inside of a microwave oven is going to have a very strong power density, because it is designed to create a thermal effect, which only occurs at power densities greater than 100 milliwatts/centimeter².  The power density of a cell phone is less than 1 milliwatt/centimeter², so the energy dissipates too quickly to heat tissue.  Even so, a cell phone can be pressed to the ear for hours at a time, so the Federal Communications Commission regulates the output of all cell phones and other devices that use wireless transmission.

Power density decreases rapidly with distance.  A smart meter on the outside wall of the house is a thousand times less exposure to a resident inside than talking on a cell phone would be.  Even baby monitors, cordless phone bases, and wireless routers expose you to more radio waves than smart meters.  Some people claim that they experience headaches or nausea when exposed to these devices, but controlled experiments have demonstrated that people experience the same symptoms if they are just told that they are being exposed but really aren’t.  Humans cannot perceive radio waves, just as they cannot perceive X-rays.  We do not have “eyes” for those frequencies.  Put the issue in perspective:  if you are comfortable with a cell phone, don’t worry about the much smaller risk from a smart meter.

The other main objection to smart meters is that they are an invasion of privacy, that the city might check how often you use your margarita machine.  Electricity is electricity; a meter cannot distinguish your toaster from your hair dryer and it can’t figure out what kind of videos you are watching.  A “smart” meter is just not that smart.  Once again, your phone is the guilty party.  Your service provider knows who you call, what you Google, and where you are at any moment of the day.