Many of the arguments against new metering technology simply don’t add up, writes Phil Kreveld.

About 1.3 million smart meters have been installed in Victoria – about half of the planned installations – but practically nowhere else is getting them in domestic settings.

In Queensland, smart meters are seen as representing an intrusive Commonwealth, and other state governments are cool on the need for them.

Yet smart meters have a tangible advantage: they allow consumers to shape their electricity consumption to capitalise on lower tariffs (the use of pool pumps, airconditioners, etc).

Smart meter technology replaces the electro-dynamic spinning disk watt/hour meter (often referred to as the Ferraris meter).

The smart meter is sometimes referred to as an interval meter. What makes an interval meter ‘smart’ is its two-way telecommunication ability with an electricity provider. The methods of communication used in the Victorian rollout of smart meters is mainly ‘mesh radio’, and some WiMAX.

Mesh radio architecture is a first step towards providing a high-bandwidth network over a specific coverage area.

The architecture is, in effect, a router network minus the cabling between nodes (individual smart meters). It is made up of peer radio devices that don’t have to be cabled to a wired port – just like conventional wireless local area network access points.

Mesh architecture sustains signal strength by breaking long distances into a series of shorter hops (between meters). Intermediate nodes boost the signal and co-operatively make forwarding decisions based on their ‘knowledge’ of the network, thus performing routing. Mesh radio operates on a frequency of 900MHz.

WiMAX has features similar to WiFi. Drawing on hundreds of experts in the telecommunications industry, the Institute of Electrical and Electronics Engineers (IEEE) has established a collection of wireless Standards:

> IEEE 802.15, also known as Bluetooth, for personal area networks;
> IEEE 802.11, also known as WiFi, for local area networks;
> IEEE 802.16 for metropolitan area networks; and,
> IEEE 802.20 for wide area networks.

Unlike WiFi, WiMAX has a range typically measured in kilometres rather than metres. The main difference between the two Standards is that WiFi is focused on local area networking technology and WiMAX is a metropolitan area network technology. WiMAX uses a frequency of 2.4GHz.

Smart meters are invoking some extreme reactions in certain quarters of the community – reactions that electricians need to be aware of so they can deal with questions raised by customers.

The chief concern expressed is that of health hazards from the electromagnetic radiation emanating from meters. The manufacturer (Silver Spring of the US) of the mesh radio platform used for many smart meters in the Victorian roll-out provides a comparative radiation exposure as shown in Table 1.

Victorian smart meters were tested in the facilities of EMC Technologies at the behest of the State Government.

The results showed that smart meters fall well inside safety standards imposed by the Australian Radiation Protection and Nuclear Safety Agency. The statements above will be challenged by some – not all of them conspiracy theorists. However, we do live in an ‘electromagnetic soup’ whose potential effects include cancer, headaches, sleep disturbance, and Alzheimer’s disease.

Peer-reviewed fields of research include cancer, reproductive effects, neurodegenerative disease and lipo-atrophy (loss of fatty tissue). These are difficult areas, and scientific investigation to discover various interaction models of electric and magnetic fields is very open as to mechanisms.

For example, one theory proposes that magnetic fields can interact with intra-cellular components including DNA. Another model shows the possible action of an electric field ‘opening’ so-called gated channels on the cellular surface. Vibration of free ions in the plasma surrounding the cell causes voltage-sensitive protein gates to open, thus disturbing the electro-chemical balance in the cell.

Environmental hazards for epidemiological studies are classified by the International Agency for Research on Cancer into groups, from 1 (carcinogenic to humans) to 4 (probably not carcinogenic). Power frequency electromagnetic exposure is summarised into groups 2 and 3 (limited evidence for magnetic fields, and inadequate evidence for electric fields).

However, even though there may be relatively weak links between effect and possible cause, there are areas of concern.

Not everyone will be satisfied with the foregoing information, as there are websites that make alarming statements.

Epidemiological studies are very complicated, and an apparent correlation between, say, a smart meter and nearby plants dying off doesn’t necessarily establish a causal link. Furthermore, the extension to human health may well be extremely tenuous.

There are other objections to smart meters in the community. Most, if not all, are without substance, and the risk of fire following installation is among the more extreme. Investigations have shown that where fires occurred it was because of installations that were already compromised. Thus any replacement, including a Ferraris meter, could have initiated a mishap.

Other objections go to cyber attacks that might bring down an entire distribution and generation network. The networks that connect smart meters and energy providers are private and quite separate from the internet. These private networks are secured by network encryption, and robust authorisation and authentication controls.

Apart from any technological risks attributed to smart meters there are political matters (and re-election issues). The introduction in July 2012 of the carbon tax has provided new focus on electricity pricing. Rather than seeing the smart meter as a way of controlling costs through demand management and price signals to consumers, some critics believe the technology offers a way of ‘gouging’ lowincome families.

METERING MATTERS

Metering technology is important. Smart meters using electronic voltage and current sampling are capable of measuring power (kW), apparent power (kVA) and reactive power (kVAr) far more accurately than the electro-dynamic meters they replace.

This is of little concern for domestic users at present, but it is different for larger users consuming more than 160MWh annually (about 18kW averaged). The simultaneous sampling of voltage and current means that distortion due to harmonics is taken into account when metering.

Some revenue-metering smart meters are capable of measuring to the 50th harmonic, whereas conventional metering offers some response to perhaps as high as the 5th harmonic.

All of this has implications for tariffs and future tariff planning, in particular for the power factor, which is severely affected by harmonics. For example, an installation with a 0.8 displacement power factor and a 100% harmonic distortion level has an effective power factor of 0.6.

A poor power factor is the single biggest cause of network voltage regulation, so it is reasonable to assume that consumers who don’t clean up their act will end up paying much more in the future.