EV Charging, Simplified

By · January 23, 2013

EV Charging, Simplified

One of the most vexing challenges surrounding EV ownership is how apartment- and condominium-dwellers will pay for the power they use to charge their cars. Starting later this year, EVs will be able to send billing information over a power line or via wireless communications to avoid this problem.

As we wrote at the end of 2011, the HomePlug Green PHY standard enables data, such as a vehicle identification number, to be sent over a power line. The low power communications channel can send messages about the vehicle, account information, and the amount of power consumed to smart meters or to other home energy equipment.

Multi-unit dwellings are particularly challenging environments for EVs, because several customers can share a single parking spot, and the meters to account for the power consumption are often far from the charging spot and out of range for wireless communications. Sending billing data over the power line also avoids the problem of having to set up additional meters or managing sub-metering.

New Models Coming

Qualcomm Atheros was the first to market with a Green PHY chip, and startup Greenvity Community is the first with a hybrid chip that can process both power line and Zigbee communications. At the Consumer Electronics Show earlier this month, Hung Nguyen, president and CEO of Greenvity Communications, told me that multiple automakers offering EVs will launch models later this year with the company’s chips embedded. Greenvity is also working with EV charging equipment companies to similarly embed the chips in their products.

Greenvity Communications is partnering with Mitsumi Electric to create modules with the integrated Green PHY and Zigbee chips that can be incorporated into home gateways or home area networks. Nguyen said that initially smart meter companies that are using Zigbee for communications can purchase a standalone box to bridge communications between power line and Zigbee. The data would be sent from the point of charging, which could contain EV charging equipment or a simple 110-volt outlet, over the power line and then converted to Zigbee wireless data close to the meter. Nguyen expects smart meter companies to embed the hybrid chips in the future.

In the future, during overnight charging, the power line could be used to send content to a vehicle, such as maps, directions, updates of applications, or even music or videos. Utilities could send price or demand signals to smart meters, which would pass them along to EVs to instantly react to changing conditions on the grid.

Solving the billing challenge for multi-dwelling units will encourage property owners to support rather than avoid EV charging, as it can create another revenue stream while reducing the technical requirements and cost.


· · 5 years ago

Zigbee is the wrong way ahead.. Too many people have been complaining about headaches and plants dying around clusters of the smart meters.. They are simply too high a power level microwave for safety around humans. Besides the fact *NOT* being UL Listed, and many of them exploding, catching fire. Of course both the meter manufacturers and the utility say it couldn't possibly be their fault, but hard to deny when there are YouTube vids of them burning/exploding. Be sure your meter trough is mounted on Brick or Masonry and NOT on Wood. A utility in Pennsylvania just put on hold a smart meter program due to the bad publicity, and fires.. More and more people are demanding their smart meters be removed, seeing as they don't decrease rates.

My own home has a 1st generation Centron which just blabs out the acct# and reading 20 times per minute and is one way only. Its not considered a smart meter. I just am having trouble how this units microwave energy compares with one of the second generation smart 2 way zigbee meters.. Anyone know? Neither Itron nor National Grid are saying anything.

Hialeah meter (which is selling used mechanical revenue meters) is doing a booming business.

· · 5 years ago

"Too many people have been complaining about headaches and plants dying around clusters of the smart meters"

Really? I am surprised that you think it is "true". I am on PG&E and PG&E received a lot of complains about it. But I have yet to see any problems with my "Smart meter". I have taken a Spectrum Analyzer to home and tried to scan for any frequency in my house and I don't see anything popping up except for cellphones when it is receiving calls...

I have plants within few feets of the smart meter and they seem to be fine..

· · 5 years ago

The plants dying is where you have a bank of meters all trying to communicate and then they have collisions with meters transmitting at the same time/ same channel. The protocol is supposed to randomly choose one of 30 channels, but at somepoint when you increase the data rate you exponentially increase the rate of collisions. So you have the effect that 50 meters cause many times the rf transmission than 50 isolated distant meters due to the requisite retransmission of botched transmissions. Plus, many of the utility's mesh networks depend on other smart meters to 'repeater' info from others. So the end result is an RF Cacaphony. I'd be interested to see hard data on the transmitted power levels, and duration of a successful packet.

Im not sure which band PG&E uses. There have also been almost unbelievable reports of college students using 2 - 13 cfl lights, one 1/4 amp netbook, and a 1 amp compact refrigerator getting $400 electric bills. Of course they blame it on a sluggish mechanical meter being replaced with an accurate one. And there have been plenty of people complaining about inaccurate billing.

My utility, National Grid, wants to INCREASE rates (since my taxes only will pay for 50% of the Smart Meter Implementation program), so that they can have all the funds necessary for implementation. In the state rate filing, they specifically say that the purpose is *NOT* to decrease rates (of course not since they are asking for a raise), and *NOT* to provide better service.

I have several questions for the 'modern' electric utility industry.

A). If these things are so safe, why aren't the meters UL listed?

B). Glass enveloped meters (like the ones they're replacing), are only a few $ more. So why are we getting these flammable poly covers?

C). Why is there scant technical info available about the RF energy from these meters? Obviously if your bed headboard is on the other side of a meter bank, its a great cause of concern.

D). Since exploding/flammable Smart Meters can alight a wood structure, why is the National Electric Code (National Fire Protection Association - 70) not concerned about the lack of a UL listing? The wire to and from the meter trough, and everything up to the point of demarcation is under their jurisdiction for comment with the EXCEPTION of the Revenue Meter (not to hard to guess why not - the NFPA is basically based on Collusion, remember all the Aluminum Romex fires in the late '60's early 70's? Nothing in the electric code about proper installation of Aluminum until a decade later- but then you have companies such as Kaiser Aluminum on the 'advisory boards' regarding 'proper wiring methods).

To see a video on the PG&E problem, check this link:


· · 5 years ago

@ Modern Marvel Fan

Its not what I think. Here is a case of a single smart meter killing a shrub. read the extended text accompanying the video:


New to EVs? Start here

  1. Seven Things To Know About Buying a Plug-In Car
    A few simple tips before you visit the dealership.
  2. Incentives for Plug-in Hybrids and Electric Cars
    Take advantage of credits and rebates to reduce EV costs.
  3. Buying Your First Home EV Charger
    You'll want a home charger. Here's how to buy the right one.