>>Your meter talks to the DCC. Their server downloads half hourly data from
>>the DCC. Their app downloads data from their server.
>>
>>If you buy their widget, the widget talks to your meter. The widget uploads
>>live readings to their server. Their app downloads data from their server.
>>
>>The app works however the data gets to the server, but without the widget
>>you only get half hourly readings.
>>
>>If your meter is not compatible with the DCC or the widget, you might not be
>>able to do one or the other of the above. But lack of one doesn't preclude
>>the other, since they operate in different ways.
>
>What's lacking is an obvious/easy way to see if the widget would talk to
>my meter.
For the ivie Bud, you can check it on their website:
https://ivie.co.uk/compatibility/
Other Consumer Access Device (CAD) suppliers have similar facilities on
their websites. This is reliable, because the DCC knows what meter you have
and which electricity company you are with, and the CAD approval process
requires the CAD supplier to specify which meters it works with and the
electricity company to specific which CADs they will permit on their meters.
So for the website checker it's just a simple lookup.
>The app, which is horrible by the way, says "You need a SMETS 2" - which
>I don't have - "or Glowmarkt compatible hardware" - how can I determine
>the latter?
Most people can be expected to know because they will know what they bought.
If not, then you'd need to check on the Glowmarkt website.
>ps Half hourly aggregated data isn't much use to anyone if they want to
>switch appliances on and off and see how much the household supply goes
>up and down [wasn't that the whole point of smart meter displays?]
The In-Home Display (IHD) gives real-time information, which is what you
need in this scenario. But an app which takes its data from the DCC can't.
It's worth bearing in mind that there are basically two ways for the data to
get from the meter to an app, although one of those ways has two variants:
Route 1a: meter -> DCC -> electricity supplier -> app
Route 1b: meter -> DCC -> electricity supplier -> app supplier -> app
Route 2: meter -> CAD -> app supplier -> app
Route 1 will work with any DCC-linked meter, and doesn't require any
additional hardware. If you use an app supplied by the electricity company
then you also don't need to rely on any third party system (some of which
are not necessarily guaranteed to remain free). But the downside of route 1,
in either variant, is that the display on the app can never be any more
granular than the DCC itself, which is, at best, half-hourly.
Route 2 requires an additional hardware device (the CAD), and will only work
if the CAD has been authorised to pair with your meter. It also requires the
data to go via a third party, which, again, may not be long-term reliable.
But, on the other hand, the granularity isn't restricted by the DCC (since
the DCC isn't part of the route), and therefore the app can, at least
theoretically, give near real-time information. The CAD also needs to be
connected to your wifi in order to upload the data to the cloud.
>I think my next port of call will be a clip-on ammeter with a remote
>readout. If such a thing exists. Or perhaps I can make one. The clip-on
>sensors are available 'separately' because they are part of the design
>of many EV charger systems.
Plenty of those exist. For example, one of these
https://amzn.to/3SFwPSg
added to this "smart home" network
https://amzn.to/3p8GFi0 will do the job.
Or, for a cheaper system that simply gives you a display, one of these will
do the job:
http://www.currentcost.com/product-envir.html - this particular
device is no longer marketed, but there are plenty available second hand on
eBay and the like. A lot of them were sold by, and thus branded with the
name of, an electricity supplier, but that's purely cosmetic - one with any
brand on will work with any energy supplier. I've got one branded E-on, but
it works fine with Ovo. This, for example, is one that's currently on eBay,
but a search for "CurrentCost" will find others:
https://ebay.us/7IfPBk
The CurrentCost monitor is a bit of a favourite among the hacker (in the
original sense of the word) community, because it has a socket that can
connect via USB to a PC. The official CurrentCost Windows software hasn't
been updated for some time, but there are plenty of guides on the web, along
with open source software, for getting one to communicate with, for example,
a Raspberry Pi.
Mark