Smart Utility Meters

© Brooke Clarke 2011

The failure of Tesla's electric power system is probably due to the fact that it contained no provision to meter the users.  Some utility companies do not use meters, for example the Sacramento, California water utility, since they feel the added cost of the meters, reading the meters and additional billing complexity does not make economic sense.  But for most applications metering the usage is the common practice.

The motivation for making this page was the recent mail from Pacific Gas & Electric saying they would be installing a "smart meter" in the very near future.

Photo when the new meter is installed.
There are a number of motivations on the part of P.G. & E. to install these meters
July 20, 2006 CPUC approves PG&E smart meters -

• Conduct remote meter reading
• Pinpoint outages
  
• Remote turn off/turn on capability
  
• Provide more accurate billing
  
• Prevent energy theft
• Enable two-way communication to each customer's meter
• Offer time varying rates to all of its customers
• Accurately forecast load and identify load centers
  

Electronic Wireless Meter Reading

The meters have 2-way wireless connectivity.  It may be Blue-tooth (Wiki) if so the max range is on the order of 100 m (300 feet).  The idea is that the meters can use neighboring meters to form a mesh network and so in populated areas the communication between meters and a node can cover a large area.  At the node the communication is transferred to a cell phone network and from there to the P.G. & E. central office.  In my case I'm in the forest and I very much doubt there are any neighbors within range (in addition to the distance there's hills and trees).  So I expect them to mount a lot of nodes on telephone poles in hope's of getting a cell phone signal (my cell phone only has 1 or 2 bars inside by house).  It may be that the data is low speed and can be reliable at signal levels lower than would be needed for a voice connection.

There are some who are worried about the radiation and it's effect on their health, but as far as I know there's data that says it's harmless and no data that shows a problem.

Accuracy

There was a CPUC investigation into the accuracy of the smart meters based on radical increases in monthly bills.  The meters turn out to be more accurate than the analog meters.  The rate increases came from billing changes.

Frequent Reading

The meters are read once per hour.

Orwell's Big Brother

By monitoring your utility usage big brother can get some insight if you're home and if so you level of activity.

Internet access to usage

I expect you will be able to go to a web page and see you electrical usage in the reading time interval step size.
See Your Power in My Account -

Energy Highlights
Select "My SmartMeter™" and view your Energy Highlights for quick facts on your monthly energy usage, like what your next bill is projected to be, and your average daily cost for energy.

Hourly/Daily Usage
Select "Usage" and view your Hourly/Daily usage to see your gas usage by the day or your electricity usage by the hour.

Energy Alerts
Select "My SmartMeter™" and sign up for Energy Alerts to receive your choice of a phone call, text message or e-mail letting you know you're projected to move into Tier 3 or higher during your billing cycle. You'll also receive additional alerts if you move into Tier 4 or Tier 5.

Time of Day Billing ^{Note 1}

The smart meters contain a digital clock that's set over the network so can bill at different rates depending on the time of day.  If you run an air conditioner at noon your bill is going to go way up with Time of Day billing.  It's my understanding the Time of Day billing will NOT be activated along with installation of the smart meter. 

Off Peak Load Control^{Note 1}

The idea is that you could load a smart washing machine and let P.G. & E. turn it on when the load is light.  In exchange you would get a discount in the electric rate you pay.  For big loads like an air conditioner the utility may make a free installation of a smart switch to allow remote On-Off control.  But for smaller loads it will be up to the resident to acquire a smart appliance.

Peak Load Control^{Note 1}

If you agree to this option some appliances, like air conditioners, furnaces, clothes dryers, etc. would have an On-Off function that could be activated when the system load is high.  There would be some limit on how long they could keep the appliance turned off.

House On-Off

If you didn't pay your bill they could just turn off your whole house.  When moving into a new house they could turn it on after a phone conversation were you setup your account.

Power Outage Detection

When there's a power outage P.G. & E. would notice at the next scheduled reading of your meter.  If that was many times an hour they would know right away, but if once per day it's not so good for detecting power outages.

Power Outage Mapping

Once they know there's an outage at some address I'm sure they will have a search procedure where they will query nearby houses based on the wiring of the grid, location of  fuses, etc. and will quickly know the exact location of the problem.  This will allow dispatching a repair crew instead of sending out a scout to find the problem.

Prevent Energy Theft

I'm guessing that this is about messing with an analog electric meter by using a strong magnet.  The smart meter does not use magnetic fields like the analog meter and so is immune to this hack.

Utility Inter-tie

The analog meter will run backwards if you are putting power back into the grid.  This was not a recommended practice by P.G. & E., they wanted you to have a separate meter just for that purpose.  It may be that the smart meters are designed to automatically accommodate feeding power into the grid. The most common system is a solar panel array that drives a special load controller combined with the utility inter-tie AC generator.  A big advantage of this type of system is that it's does not need a bank of batteries that have limited life and are expensive.

Note1 - For residential customers as of July 2011, you must agree to time of day billing.  But you can see that large commercial and industrial customers have no choice except to be on Time of Day billing.
CPUC - The Benefits of Smart Meters -

ACEEE Study Finds “Smart Meters” Not Smart Enough to Slash Residential Power Use and Significantly Reduce Consumer Electric Bills
In order to save electricity an "In Home Display" or a real time internet feedback system is needed that not only lets you know how much electricity you're using but also can let you know how well you're doing in relation to similar houses that are nearby.  For example if a neighbor has a similar house but a much newer air conditioning system how much difference is there in monthly bills for the same time period.  Substitute and other appliance name and do the comparison.