IT & Automation
proficiently, will also confer a number of extra benefits such as in-field upgradability, ownership of the design, flexibility of manufacture and supply chain control. One of the key ways to build for the future is to specify a meter with a larger flash memory capacity – this provides the ability to store firmware images for upgrade purposes, and to record rich, deep data to support future applications such as usage profiling and load disaggregation, for almost no additional cost. Using industry standard processor architectures and hardware interfaces between functional blocks means that, as new improved versions of devices become available from different manufacturers, it is relatively easy to update the design to take advantage of them, and mitigate the risk of component obsolescence. Considering the capability to deliver additional functionality, even if not implemented in the initial firmware, is also likely to extend the useful life of the meter.
Product replacment Traditional meter manufacturers have built their businesses and manufacturing up around the model of a steady ongoing replacement of product as it reaches the end of its working life. Te new waves of smart meter deployment require much larger volumes of meters to be delivered over short periods of time, something that not all traditional manufacturers have been prepared for. Tis has been evident in North America, where the current rate of electricity meter installations is approximately five times higher than the historical replacement rate. Tis rapid fluctuation of the supply volume is very familiar to the world of consumer electronics, where products are typically manufactured in high volume by contract manufacturers for relatively short production runs. Capacity can be scaled up and down relatively quickly, and at multiple plants if needed. At the end of the product design life, or a particular wave of installation, the contract manufacturer simply reassigns the production facilities to build different products. By contrast, traditional meter manufacturers who have invested in their own capital-intensive production facilities may struggle to meet these peaks in demand,
Specification questions
S
ome of the more obvious specifications relate to, for example, the quantities to be measured and
their accuracy limits, the time-of-use tariff structure, and minimum frequency and reliability of remote reading. The harder ones relate to ill-defined
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www.engineerlive.com and evolving requirements – for example:
● Will it need to be paired with a home energy monitor, to help engage customers, and what sort of depth and resolution of
data will this require? ● What communications means and protocols will it need to support out of the box, and in the future? Does it need to communicate with other smart meters – maybe an electricity meter that’s already installed, or perhaps one that might be
installed later? ● What types of smart grid functionality
will be needed in future – load shedding or time shifting of smart appliances, or
control of the charging of electric vehicles? ● How will it integrate with future distributed local generation and manage
future feed-in tariff changes? ● It’s hard to predict and build in all these diverse requirements today, so which hooks and features for adding them in remotely do we need to include? ●
and have to carry the cost of the line and employees when orders are low – these costs all have to be passed onto the utility as part of the product price, and might affect the cost or payback of the rollout because it is extended over a longer period. For utilities specifying meter design, the ability for the finished product to be built by a contract equipment manufacturer (CEM) is an important part of the design challenge. Tis ranges from taking advantage of the tremendous buying power of the CEM by using components widely used in other
Fig. 2. OnStream smart electricity meter.
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