Measuring building power useage

[Nick]

I'm in the process of installing one of these:

Emporia Smart Home Energy Monitor with 16 50A Circuit Level Sensors | Real Time Electricity Monitor/Meter | Solar/Net Metering https://smile.amazon.co.uk/dp/B08CJGPHL9...WGYBQ134C3

It's very accurate, typically within a very few % (some say 1%) of the utility meter. My configuration is different to the one I've linked to - I have three 200A sensors and 8 x 50A wide aperture sensors.

It's circuit-based rather than outlet-based as its intended to be installed in a consumer unit.

As we have a reasonably complex 3-phase feed to our property, I'm installing one in our meter cupboard.

This is more complex than a CU installation as effectively I'm having to make a small CU for safety reasons.

I like the architecture and it's, IMHO, very reasonably priced. The unit handles single or three phase utility feeds up to 200A and up to 16 x 50A circuits. It monitors voltage and current drawing its own power (40mA) from one of the phases. It uses your WiFi and the app is cloud-based. There's a range of different sensors, e.g. I'm using wide-aperture CTs as rather than clipping onto 2.5mm circuits in a CU, my CTs are having to fit 10+mm meter tails.

Fairly new to the UK - the company is very popular in the USA.

   
   

[Nick]

The simple plugs are ok for individual comparisons - they have variable accuracy but are ok for simple stuff.

Chalk vs. cheese compared with the system I'm putting it, which records and costs out circuits, provides trend and historical data plus much much more for up to 16 circuits at a time.

If you need more than 16 circuits monitored (we have about 30 in our house, plus workshops, an office building, sauna & a cottage), you can add more units. However, in our case we're looking at the utility supplies rather than the individual circuits.

[ppppenguin]

I'm thinking about energy monitoring for the BECG's premises at Hemswell Cliff. It's 100A 3ph and we have a smart meter. We can't find a way to link the little readout unit to a PC or network. In any case the meter is in an external hut and can only just communicate with the readout unit when it's in the building. This image shows the meter/intake hut in the foreground. It's the small one with a pitched roof: https://goo.gl/maps/BwNtD9w4dHuiiFor9 There's a dashboard on the Octopus website but it's far from real time. There's an API which I suppose we could try and use.

I don't think we need a breakdown of usage by sub-circuit, so a monitor which clips on the 3 phases at the main switch would work. Any ideas on what to buy?

A complication is that we should be fitting a 30kWp solar panel array soon. Subject to G99 consent from Northern Powergrid. The smart meter will be able to measure reverse power for the Smart Export Guarantee and the inverter will have a network port. It would be nice to integrate all the information into a single dashboard that we can monitor both locally and remotely.

[Nick]

I'm 100A three phase here. The unit I refer to above handles up to 200A three phase utility and up to 16 x 50A sub-circuits.

I does have solar panel awareness but I'm not sure how that works...

[PerdioPal]

Does it tell you which phase the sub circuits on? I guess it must know to do PF measurement.

I does stuff with PF but as yet I'm still building the infrastructure so it'll be a few days before I have a proper play with it.