The Case for Sub-Metering

The guide to Automatic Monitoring and Targeting

If you don’t have sub-metering all you really know about your utility or energy consumption is – how much? And perhaps when?

You may know this monthly or you may have more granular data if you have Half-Hourly metering (and your meter operator has a web portal that you have access to), but this is defined by the fiscal meters that you have installed. You may be able to identify wastage from a baseline, but have no idea where or what that waste is attributed to.

As soon as you install sub-metering, you add a where and a definite when to your information sources and that is a very different thing knowing how much, when it took place and where it took place.

With the installation of sub-metering you are in far stronger position in terms of the granularity of data you hold and what you can do with it.

With sub-metering you can:

  • Reduce waste down at the point where it is taking place
  • Evaluate plant and equipment (and then optimise it)
  • Ensure plant performs to expectation (including new equipment)
  • Raise awareness and encourage/enforce best practice (combined with the right software front-end)

Taking the last point, a sub-metering solution combined with the right software can help to raise awareness with everyone within your organisation via a web-based front end, particularly if it has dashboards and a platform area for the invited audience.

Highlighting via the granular data you now have, the area relevant for them, to show data for example on their area (kitchen/canteen for example) to capture their interest and support your continual reduction strategy

The Technology

There are many different technical terms for sub-metering that actually relate to the data acquisition technology or features that are used.

These include:

Modbus | M-Bus | profibus | UHF | sms | LoRa |GPRS | ZigBee | 3G | WiFi | https | sftp

Metering Data Acquisition Technology Types

You will probably engage a contractor to help you, but there are a few things that you need to be aware of, because not all providers have the same approach.

Generally speaking you tailor the system that gets delivered to what the client, the site and what the user expectations actually are; rather than to try and make a particular technology fit the site.

The right technology has to give you:

  • Data portability (i.e. take data from that location to where it’s needed, cloud, locally etc.)
  • Future Proofing (not just the technology, but in how the installed system is understood by you)
  • Hardware Interfaces (keep on using as much existing hardware and infrastructure as possible)

In particular, around the concept of future-proofing, consideration must be made to the fact that internal staff with the knowledge of the system may move on and this has the potential to cause problems. For example, if a system is installed by an individual whose position  is now succeeded by another, it is now somewhat problematic to attain what is needed from the system, and as a result this can cause significant changes to the way of working.

A lot of this goes on and it’s fairly easy to make sure that it doesn’t. What you want to do is put a system in that once you’ve long gone on after being promoted is still working, even if put in a decade ago. Still fit-for-purpose, meeting your original objectives and still does the job!

This should all be aligned with the site considerations and performance expectations as alluded to earlier.

The site topology – the kind of site that you are metering will have an impact on the type of technology that you should employ to make the system work effectively and what are you expecting the system to do in terms of the need for a simple or complex design.