Compos Mentis

If data is information, and if more information is always good, then more data is always better. Wait, that can’t be true!

Too much data can swamp any system. Too much data can obscure the information embedded in it unless there is a means for recognising useful data and culling out meaningless data. Too much data is expensive to deal with. In everyday life we intuitively learn to acquire and process enough data to make decisions and act accordingly. People who cannot make good decisions, even with ample data at hand, have a problem in life.

For one hundred years the primary objective of residential electric metering in North America has been to capture a single piece of data for each customer per month – a single number related to total energy consumption in the billing period. Early multi-register induction meters allowed time-of-use rates to be offered by capturing two or three pieces of data each month, adding peak and shoulder-peak consumption accumulation data to the total energy data, from which off-peak energy is computed. So we had three or four pieces of data per customer per month

Then there was load survey metering. It has historically consisted of acquiring a continuous sequence of consumption readings, each usually representing consumption in a 15 minute interval. These load survey data were acquired with magnetic tape recorders that typically captured up to 40 days worth of time-tagged 15 minute interval data. The recorder tapes were manually recovered monthly, a cumbersome process. By the early 1980s the mag tape recorders were replaced by a solid state equivalent with a communications modem, allowing data recovery over a phone line. These load survey data recorders captured 96 pieces of data per day per customer, and tacked on the time tags and customer ID. They are still available and are widely used.

UNNECESSARY DATA Lots of data! Yes, but not from lots of customers! In fact, the load survey data on residential customers is needed only for a few hundred or, at most, a few thousand customers – just enough to constitute a statistically valid load profile of a given class of customer. The data, in turn, is used for load studies and rate design analysis. Three thousand pieces of 15 minute data are not needed for billing residential customers!

Now leap forward to 2008. Now we want to convey electric price signals to consumers. In the new world of buzzwords and acronyms there is the notion that every product must be ‘smart’. We are now specifying, designing and deploying systems composed of ‘smart meters’. We call them AMI systems – advanced metering infrastructure. Now define AMI.

Now roll out the concept of ‘smart grid’, and acknowledge that AMI is the crucial component of the smart grid. Now define ‘smart grid’.

Your definitions of AMI and of “smart grid” may be different from mine. And yours may be different from the next person’s too. That’s OK. But if your utility is going to buy an AMI system or invest in the smart grid, the definition you choose should correspond to what your utility wants to do – not to some bizarre definition by some heavily lobbied congressman or state legislator whose limited knowledge of this arcane field was acquired from someone whose commercial interests are specifically tied to that definition.

MANAGING THE METER READINGS OK, let me be specific. Today’s AMI systems are universally designed to provide hourly interval data from each customer. Hourly data is generally conceded to be of sufficient resolution for any residential metering application – except for acquiring load survey data from a small sample of customers, mentioned above. Hourly data floods the utility in 720 meter readings per customer per month, where before there was a single reading per month – except for a small number of TOU metered consumers. That’s a lot of data, but suppliers of Meter Data Management Systems have created the products that will juggle all this data. So far, so good.

But now things really start to get a bit crazy. There is a misguided idea that AMI systems, as part of any “smart grid” system, must collect 15 minute interval data from all customers all the time. That is abject nonsense! Show me why you need that data! Sure, any meter should be capable of providing 15 minute data when asked to do so, and that will allow convenient and cost efficient recovery of that load survey data we talked about. But we will need that for only a few hundred or, at most, a few thousand meters. We do not need 15 minute data from all residential meters all the time!

Unfortunately, the notion that 15 minute data must be acquired from all meters all the time is finding its way into draft legislation in California, the regulatory requirement of several other states, and even some legislation at the federal level. There was even a notion that 5 minute interval data was required! If you ‘follow the breadcrumbs’ backwards from the source of this legislation you will find that the name of one or more communications technology suppliers crops up again and again. One such supplier lobbies legislators with the notion that a flood of (excess) metering data combined with a hazy notion of smart grid data streams will require a broadband data pipe. The argument is, “If some data is good, more must be better, so you need a fat pipe!"

Misguided legislation that forces unrealistic requirements on utilities is counterproductive, because utilities who know better will resist doing stupid things. The self-serving suppliers do a disservice to the industry they claim to serve, and harm its best interests with artificial “requirements,” distorted definitions and biased standards.

Utilities and responsible vendors must stand together and speak loudly and soon when bogus requirements are made part of legislative or regulatory requirements. Vendors who seek to sell to legislators and regulators first, and to utilities later, deserve to lose the respect and business opportunities our industry offers to its responsible suppliers.