Benpointer Posted June 17, 2022 Share Posted June 17, 2022 Hi all, I am thinking of buying an Emporia Gen 2 Vue Energy Monitor with 8 or possibly 16 50A sensors to help further improve our energy efficiency. We have an all-electric, well-insulated house but the running costs are now going up with recent energy price rises. The house has underfloor heating run from a Mitsubishi Ecodan 85 ASHP. We also have 4kW of PV panels, solar hot water and MVHR. I'd like to be able to monitor the electricity use in detail hence the potential Emporia purchase. I know these devices hold the data on a cloud, with potential future risks that that poses but still they seem the best option at the moment. I have some questions which I cannot get clear answers to from the Emporia website. If someone has one of these units or knows the answers to my questions, I'd appreciate any thoughts... The device has two 200A clamps which need to go around the L and N supply leads into the distribution box. Why both leads? Just curious. Does this device measure the live voltage or make a voltage assumption to calculate the power level? Can I measure the PV panel output on this device too? If so how? If we are feeding into the grid will the monitor distinguish that, or see the power going through the supply leads as an absolute value (i.e. will a 1kW feed into the grid from our PV panels look like we are using 1kW from the grid?) The instructions say the clamps have to be fitted inside the consumer unit (CU). Anyone know why? The issue for me with fitting them inside the CU is that the ASHP, UFH, MVHR and solar water are all on one CU circuit, so I wouldn't get any granularity about the individual demand from each of those devices... ...Also, is it safe to open the consumer unit to fit those clamps, if the main switch is off? (Obviously I can be careful not to touch any bare wires but it sounds a bit scary to me!) If I clamp a 3-core cable (e.g. the individual supply to the ASHP) would I get a double reading, or zero? (i.e. would the currents running through the live and neutral wires be added together or cancel each other out?) Sorry, that's a lot of questions but if anyone can answer some of them, I'd be grateful. Many thanks Benpointer Link to comment Share on other sites More sharing options...
SteamyTea Posted June 17, 2022 Share Posted June 17, 2022 Before you go and buy a monitor that has very comprehensive (on paper) capabilities, have you got a meter already set up that can log the usage? A few of us on here have modified cheap ones to add logging. Knowing what each device/circuit is doing, and when, can be useful, but it does not, in itself, change usage and habits. Leaving a 3W light in will take 20 minutes for the main meter to register it (1Wh). Leaving the hot water cylinder on to make sure there is always a constant supply of piping hot water will take 1.2 seconds for the meter to register it. Reduce the time heavy loads are running. Just use what you need to. Turn off gaming machines and anything that needs auto updating. Link to comment Share on other sites More sharing options...
Benpointer Posted June 17, 2022 Author Share Posted June 17, 2022 10 minutes ago, SteamyTea said: Before you go and buy a monitor that has very comprehensive (on paper) capabilities, have you got a meter already set up that can log the usage? A few of us on here have modified cheap ones to add logging. Knowing what each device/circuit is doing, and when, can be useful, but it does not, in itself, change usage and habits. Leaving a 3W light in will take 20 minutes for the main meter to register it (1Wh). Leaving the hot water cylinder on to make sure there is always a constant supply of piping hot water will take 1.2 seconds for the meter to register it. Reduce the time heavy loads are running. Just use what you need to. Turn off gaming machines and anything that needs auto updating. Thanks for the reply SteamyTea. Have I got a meter already? Only the BG smart meter which does not work most of the time 'because of cellular phone issues'. I could probably manage to link an Arduino to a cheap meter to do some logging (I have done some Arduino projects before although I am a bit rusty now) but I am not sure I want to devote the time to that if I can buy something off the shelf for £100 or so. Some of the questions I want to answer are not to my mind obvious. For example, our ASHP has always been 'on' 24/7/52, with usage controlled entirely by the room stats (so it's not really operating this time of year). This works well from a comfort pov, but is there a background load? How much does our pond pump and filter cost us to run? Should I keep the MVHR running through the summer? Could we run certain things at a time better optimised to use the PV power we generate? etc.etc. Link to comment Share on other sites More sharing options...
SteamyTea Posted June 17, 2022 Share Posted June 17, 2022 (edited) 14 minutes ago, Benpointer said: Some of the questions I want to answer are not to my mind obvious. Fairly easy to disaggregate if you know the power of items. I noticed that my fridge was constantly on as my usage went up. Go around and jot down the power usage of each item. Then buy this, https://www.ebay.co.uk/itm/225026280748 a RPi Zero W and get some free code. Job done for 30 quid. Just seen you have an Ecodan. You may have real reasons to be concerned about usage. As you are in Dorset, @Radian is local and knows a thing or two about monitoring. Edited June 17, 2022 by SteamyTea Link to comment Share on other sites More sharing options...
Benpointer Posted June 17, 2022 Author Share Posted June 17, 2022 Thanks I will take a look at that. Yes, I read the thread about the Ecodan base load concern - I am not sure if there was a conclusive answer though? It's one of the reasons why I want to start monitoring. Link to comment Share on other sites More sharing options...
SteamyTea Posted June 17, 2022 Share Posted June 17, 2022 6 minutes ago, Benpointer said: I am not sure if there was a conclusive answer though Stick one of these on it. https://www.ebay.co.uk/itm/354031328769 Link to comment Share on other sites More sharing options...
joth Posted June 17, 2022 Share Posted June 17, 2022 1 hour ago, SteamyTea said: Stick one of these on it. https://www.ebay.co.uk/itm/354031328769 This only really helps if you leave it unused on standby for days at a time (i.e. don't use it for DHW, or for cooling in summer). Otherwise I've found 10s granularity logging much more useful. (I have a home assistant sensor setup for my ecodan) Link to comment Share on other sites More sharing options...
joth Posted June 17, 2022 Share Posted June 17, 2022 3 hours ago, Benpointer said: I have some questions which I cannot get clear answers to from the Emporia website. If someone has one of these units or knows the answers to my questions, I'd appreciate any thoughts... The device has two 200A clamps which need to go around the L and N supply leads into the distribution box. Why both leads? Just curious. Does this device measure the live voltage or make a voltage assumption to calculate the power level? Can I measure the PV panel output on this device too? If so how? If we are feeding into the grid will the monitor distinguish that, or see the power going through the supply leads as an absolute value (i.e. will a 1kW feed into the grid from our PV panels look like we are using 1kW from the grid?) The instructions say the clamps have to be fitted inside the consumer unit (CU). Anyone know why? The issue for me with fitting them inside the CU is that the ASHP, UFH, MVHR and solar water are all on one CU circuit, so I wouldn't get any granularity about the individual demand from each of those devices... ...Also, is it safe to open the consumer unit to fit those clamps, if the main switch is off? (Obviously I can be careful not to touch any bare wires but it sounds a bit scary to me!) If I clamp a 3-core cable (e.g. the individual supply to the ASHP) would I get a double reading, or zero? (i.e. would the currents running through the live and neutral wires be added together or cancel each other out?) I've been looking a bit at Emporia too, as I'm underwhelmed by the emonpi I currently use. 1. The UK instructions only seem to have one 200A clamp. The versions with 2 main clamps i think are the USA deign and they have split-phase supply there, so it just happens to have the 2 clamps out of box. Looking at the install manual seems to confirm: they have one clamp on red, one on black, which is the L1 and L2 two-phase hot wires in USA. (White is neutral). 2. Yes, this is step 8 in the above manual 3. They also sell a solar suppliment, not sure why that would be needed maybe just if you have >16A of solar. 4. ?? The HW supports it, but it's up to the app used as to how well it displays it ? 5. The clamps need to go over the L wire only, not the L and N as they will cancel each other out. Inside the CU is the only place where the wires should (reliably) be individually accessible in a standard install. Else you'd need to split open all the T&E to pull a core out and clamp, which would be non-comformant 6. Yeah that's a lot of stuff on a single circuit. Ours is split across 3 (ASHP outdoor unit, heating controls, MVHR). 7. Fairly safe, but there is still live power going to the main switch, non-RCD protected. It's better if you have an upstream 100A breaker for the whole house at shut that off. Apparently some supplier meters include a main switch. Probably the main risk is you disturb something and cause a hazard when turned back on. It can get very crowded with all these CTs in a UK style CU. (USA breaker panels are much more spaced out) 8, zero. See #5 FWIW I'm not interested in using the Emporia cloud/app function and would only use it if I can get it working local connection only. It is possible but bit of a hack. As this jolly guy says they should just support this out the box: 1 Link to comment Share on other sites More sharing options...
billt Posted June 17, 2022 Share Posted June 17, 2022 It's worth looking at the Iotawatt. https://iotawatt.com/ They don't advertise, so you won't have heard of it, but having tried the Emon devices, the Brultech GEM and Brultech ECM, the Iotawatt is the best of these. (I wouldn't consider the emporia - don't like cloud dependency.) It's a development of the Emon monitors, but it's a neat solution, logs locally (but can upload to other databases). I've just bought my 4th, arrived from the US in just over a week. It will do everything that you list, it uses a voltage transformer for a voltage reference, so measures power correctly. 3, you just put a CT on the feed from the PV inverter. 4. The Iotawatt can record either the actual power on a circuit, including direction, or it can just log positive or negative power. 6. Presumably you can get access to the individual feeds for each device so you should be able to monitor them separately. Link to comment Share on other sites More sharing options...
Benpointer Posted June 17, 2022 Author Share Posted June 17, 2022 Thanks joth and billt, lots of info there. It seems like most of my concerns can be overcome. I'll also take a look at iotawatt. Cheers Link to comment Share on other sites More sharing options...
Benpointer Posted June 17, 2022 Author Share Posted June 17, 2022 2 hours ago, billt said: It's worth looking at the Iotawatt. https://iotawatt.com/ I can only find a US site and they don't seem to have all the components in stock 😞 I can't find iotawatt on Amazon. Link to comment Share on other sites More sharing options...
billt Posted June 17, 2022 Share Posted June 17, 2022 Yes, it's a US company and they only sell direct, but they do respond promptly. They were out of stock of the 240V reference transformer when I ordered the latest one. Any 9V AC transformer should work, you can calibrate it in the Iotawatt setup. I had a couple of these left over https://shop.openenergymonitor.com/ac-ac-power-supply-adapter-ac-voltage-sensor-uk-plug/ and they work fine. The power supply is a standard 5V usb supply. Incidentally, if you're installing many CTs in the consumer unit, it's better to use small toroidal ones rather than split core as they're much more compact. They seem to be a bit difficult to get hold of here. I had some of these https://www.brultech.com/store/index.php?id_product=45&controller=product from another project. Link to comment Share on other sites More sharing options...
Radian Posted June 17, 2022 Share Posted June 17, 2022 Ah, my pet topic. Been sorting out impossible door locks and electric awnings all day so only got to this thread now 😬 But it turns out you've all pretty much got it covered (especially @joth's 8 point answer). The Emporia Gen 2 looks to be quite a decent bit of kit but I'm not impressed by their response in their FAQ about why their API is closed. To use the excuse that they're only a small team seems pretty lame to me. Does this imply that it's so poorly devised that they don't want anyone to see its workings? I doubt it. Really the free 'cloud only' option smacks of them reserving the ability to charge for this at a time of their choosing. Several high profile players have already closed down services when the cost of providing server bandwidth for free became unviable. @Benpointer If you opened up your CU would you have access to all the circuits you want to monitor? @billt is right about the benefits of the more compact toroidal CTs if you're prepared to pop a few wires off the busbar (you can use circuit Neutrals) but without lots of tinkering you might not be able to make them work as plug-and-play with the Emporia. But because of the limited cable length all your circuits would need to be inside the CU and I doubt that this would be the case. 9 hours ago, Benpointer said: I could probably manage to link an Arduino to a cheap meter to do some logging (I have done some Arduino projects before although I am a bit rusty now) but I am not sure I want to devote the time to that if I can buy something off the shelf for £100 or so. Can't fault you on that except for if it means compromising on what you really want. I've often faced this dilemma - sometimes the only way to get exactly what I want is to make it myself. For a distributed system I would point you to the PZEM-004T as the measuring device and ESP8266 or ESP32 programmed in the Arduino environment as the comms link to datalogging via MQTT. This way you can get the granularity down to a reading every second and keep all the data to yourself. You could get one up and running to begin with then replicate as often as you like. There's a Arduino Library ready to go for talking to the power measuring module. Link to comment Share on other sites More sharing options...
SteamyTea Posted June 17, 2022 Share Posted June 17, 2022 5 hours ago, billt said: It's worth looking at the Iotawatt. https://iotawatt.com/ Can you export the raw readings as a *.csv file for easy playing about. This is what mine (home made) churns out. Time, temperature, power. 01/06/2022 04:49:34,19.5,02749 01/06/2022 04:49:39,19.5,02753 01/06/2022 04:49:45,19.5,02755 01/06/2022 04:49:56,19.5,02755 01/06/2022 04:50:01,19.5,02753 01/06/2022 04:50:07,19.5,02740 01/06/2022 04:50:13,19.5,02744 01/06/2022 04:50:24,19.5,00294 01/06/2022 04:50:29,19.5,00196 01/06/2022 04:50:35,19.5,00147 01/06/2022 04:50:41,19.5,00117 01/06/2022 04:50:52,19.5,00084 01/06/2022 04:50:58,19.5,00073 01/06/2022 04:51:03,19.5,00065 01/06/2022 04:51:09,19.5,00058 01/06/2022 04:51:20,19.5,00049 01/06/2022 04:51:25,19.5,00045 01/06/2022 04:51:31,19.5,00042 01/06/2022 04:51:37,19.5,00039 01/06/2022 04:51:48,19.5,00034 01/06/2022 04:51:53,19.5,00032 01/06/2022 04:51:59,19.5,00030 01/06/2022 04:52:04,19.5,00000 01/06/2022 04:52:15,19.5,00000 01/06/2022 04:52:21,19.5,00000 Link to comment Share on other sites More sharing options...
billt Posted June 18, 2022 Share Posted June 18, 2022 I'm sure that you can, although it's not something that I've done. I think that it uses a modified version of the Open Energy Monitor CMS so the data is there. I upload to a local EmonCMS instance and that does all the processing that I need. If you want any more information https://docs.iotawatt.com/en/master/ should tell you all that you want. Link to comment Share on other sites More sharing options...
Benpointer Posted June 18, 2022 Author Share Posted June 18, 2022 36 minutes ago, billt said: I'm sure that you can, although it's not something that I've done. I think that it uses a modified version of the Open Energy Monitor CMS so the data is there. I upload to a local EmonCMS instance and that does all the processing that I need. If you want any more information https://docs.iotawatt.com/en/master/ should tell you all that you want. Thanks! I'll take a look Link to comment Share on other sites More sharing options...
SteamyTea Posted June 18, 2022 Share Posted June 18, 2022 41 minutes ago, billt said: I'm sure that you can Looks useful. Link to comment Share on other sites More sharing options...
Bramco Posted June 20, 2022 Share Posted June 20, 2022 On 17/06/2022 at 15:47, joth said: I've been looking a bit at Emporia too, as I'm underwhelmed by the emonpi I currently use. Just out of interest, what underwhelms you about the emonpi? I've run the open energy software on a home baked system for quite a long time and haven't had any issues with it. Of course if you want to monitor individual circuits then you'd need something else - but the Emporia system seems to be a less useful system than emonPi or the emoncms software on your own system with an emonTx. On monitoring individual circuits, I can see the need if you suspect your Ecodan is using a lot when idle but for everything else, read the back of the device and understand what each item you turn on uses. Regularly monitoring your washing machine is like expecting to save energy because you have a display attached to your smart meter - it doesn't. Simon Link to comment Share on other sites More sharing options...
joth Posted June 20, 2022 Share Posted June 20, 2022 The emonpi SW stack and HW looks nice, but just been a long battle through small niggles. - limit on number of circuits, and expensive to expand - emonTX being the best way to expand but still only 4 circuits and insists on an unnecessary and unreliable wireless link - the sampling frequency of the emonpi is slower than I expected (not fast enough to control PV redirect, really) - it's possible to increase frequency but requires manually flashing the embedded micro-controller and it's really easy to get micro-controller and pi stack speaking incompatible versions - after doing the micro-controller manual FW flash any Pi SW updates break it. - the graphical editor for managing data feeds and measurements always catches me out and i have to mess with it multiple times to get it to do what I want it to - I don't really want my logging inside a pi, as it wears the SD card, so I do most the real work on a bigger machine with Raid drive and influx+grafan anyway, making the Pi rather overkill for my needs - (slightly related) I also got the OpenEVSE which came with a duff wifi board (ESP32) that was a bit more hassle to repair etc Absolutely no point is unfixable, but for what I thought would be a fairly easy plug and play setup, it's taken a heck of a lot more tinkering than I had expected when I set out, whereas everything I've put ESPhome on has been simpler than my expectations for effort needed, hence feeling attraction to the Emporia. Link to comment Share on other sites More sharing options...
Bramco Posted June 20, 2022 Share Posted June 20, 2022 21 minutes ago, joth said: The emonpi SW stack and HW looks nice, but just been a long battle through small niggles. - limit on number of circuits, and expensive to expand Agree but as per my post, in a normal house, why would you wan to monitor individual appliances - it's not going to really tell you a lot, except what's already on the back of the appliance. I found that with one CT on the main feed, I could seen what our base load was, could see the fridges turning on and off at night and also see when the washing machine went on etc. - although of course I knew full well when I'd put the kettle on or the dishwasher on. So actually base load was the only information that helped me to reduce our bills. 25 minutes ago, joth said: - emonTX being the best way to expand but still only 4 circuits and insists on an unnecessary and unreliable wireless link You can attach it serially or with a cheap esp board via wifi - I have to admit the RF link is the weakest link ;-D 26 minutes ago, joth said: - the sampling frequency of the emonpi is slower than I expected (not fast enough to control PV redirect, really) You need to be a heck of a lot faster for PV divert and there are diy instructions on the open energy monitor site with sw to accomplish this. I've had one based on Martin's sw running for several years without a hiccup. If you bought a commercial diverter, then you could still have a CT on the PV circuit to monitor generation 29 minutes ago, joth said: it's possible to increase frequency but requires manually flashing the embedded micro-controller and it's really easy to get micro-controller and pi stack speaking incompatible versions - after doing the micro-controller manual FW flash any Pi SW updates break it. I thought they'd fixed this? But I don't use an emonPi, only the sw - and to be honest, it hasn't been updated since it was installed - but it works, so I'll only change things if I need to. 31 minutes ago, joth said: the graphical editor for managing data feeds and measurements always catches me out and i have to mess with it multiple times to get it to do what I want it to Yup - but then again, if you've got a functioning interface why change it? 32 minutes ago, joth said: I don't really want my logging inside a pi, as it wears the SD card, so I do most the real work on a bigger machine with Raid drive and influx+grafan anyway, making the Pi rather overkill for my needs Well don't then, it's east enough to redirect it to something more suitable. There was a lot of discussion about SD card wear on their forum a few years ago and the solution they found seems to work as there haven't been any problems related to SD card wear for a few years. The Pi isn't overkill although the emonPi might be - just set up a Pi zero - our system has been running on a Pi zero with a usb drive for ages. We're about to move into our new build and I'll just repurpose all the old hardware, Pi zero, emonTx etc. but rebuild the system with the latest sw. Although I'll probably get rid of the RF interface between the pi and the emonTx - that wasn't the best solution. Btw have you seen the latest developments - more along the lines of iotaWatt - https://community.openenergymonitor.org/t/avr-db-emontx-v4-new-hardware-in-progress/20209 Simon PS I have nothing to do with these guys - just a customer - but found the openness of the hw and sw a great feature - as well as not being in hock to some cloud. Link to comment Share on other sites More sharing options...
joth Posted June 20, 2022 Share Posted June 20, 2022 (edited) The reason for more CTs is to track actual annual stats on energy consumption, it would be nice to gather for the passive house DB and people are always asking. They typically want to know about energy used in heating, lighting, generation, and everything else. So if doing it properly, this would be monitoring for: - ashp - heating controls - electric floor mats - towel rads - immersion heater - lighting (4 circuits but could jam 3 of them in one CT) - ovens and hob (3 circuits, although I've evil jammed them into one circuit) - quooker (I have this on an tuya/ESPHome smart plug) - car charger - PV inverter - (battery when we get it) - everything else. I don't deny open SW and HW stack is worth a lot, and I don't regret any of the £ I have thrown them over the last 2 years towards supporting that. Just as I'm thinking forward to help other setup similar systems, I feel due diligence is comparing the field a bit more first. Edited June 20, 2022 by joth Link to comment Share on other sites More sharing options...
Radian Posted June 20, 2022 Share Posted June 20, 2022 6 minutes ago, joth said: quooker (I have this on an tuya/ESPHome smart plug) You may have noticed that I'm a big fan of these! ~£12 for an energy monitor that talks over MQTT and can be turned on and off as well - just heaven. The only grumble is how hard those cases are to pull apart to reflash the chip. I think there might be a way to do it OTA but I like to eyeball the circuit before putting it into service. You never know what you might find inside them! Link to comment Share on other sites More sharing options...
joth Posted June 20, 2022 Share Posted June 20, 2022 Just now, Radian said: You may have noticed that I'm a big fan of these! ~£12 for an energy monitor that talks over MQTT and can be turned on and off as well - just heaven. The only grumble is how hard those cases are to pull apart to reflash the chip. I think there might be a way to do it OTA but I like to eyeball the circuit before putting it into service. You never know what you might find inside them! yeah I got a box of 2NICE, which work perfectly with tuya-convert I have a couple UK style wall sockets running tuya I need to try and convert some time. this will bring a few more interesting items under control. But as you see, vast majority of stuff I want to monitor is hard-wired so really has to be CT clamp or expensive (and space consuming) din-rail mounted energy monitors. 1 Link to comment Share on other sites More sharing options...
Benpointer Posted August 20, 2022 Author Share Posted August 20, 2022 (edited) Quick update: I took the plunge with an Emporia Vue £160 on Amazon with 16 x 50A sensors. So far, so good. Here's some thoughts from the Amazon review I posted earlier today: A clever product which seems to work well. Good app and great support. This was a UK DIY install. A few notes re installing in the UK: I managed to fit 15 50A sensors in my consumer unit. It was a bit of a squeeze but it all fitted in ok (see photos) Make sure you get each sensor round the right way, they are clearly labelled 'breaker' with an arrow (in the photo, I have two sensors, 3 and 7, upside down, I fixed that before closing the consumer unit). The 16th 50A sensor went on the PV feed live, the 200A on the live from the grid supply meter. The device itself was definitely not going to fit in the consumer unit. I therefore shortened the 4-wire power lead and connected it to a two-core connector: red, white and blue leads to neutral, black to live, with some shrink wrap over the wires for neatness and to provide double insulation. You can see this in one of the photos. The other end of the connector is wired into a standard UK 3-pin plug which is plugged into a wall socket. This works fine, no need as far as I can see to wire the power lead directly into the consumer unit. I guess the only issue is that you could accidentally unplug the power lead or switch the wall socket off, at which point you'd lose monitoring of course. As our socket is in the service cupboard this isn't really an issue. I did have an issue after the install when trying to configure the device via the app. It failed at the point I told it I had solar PV. Within the app there is the option to connect to a chat support service, which I did. The guy (James) was really helpful, checked lots of things with me. He was a bit worried that the unit wasn't powered directly from the consumer unit but... eventually we discovered I had made the novice mistake of putting the 200A sensor on the live feed from the meter THE WRONG WAY ROUND (doh!) Once I flipped it, it all worked fine. Tbf I have one further minor problem - the tip of the jack plug has broken off one of the 50A sensor leads. I don't think that was me. I actually have 15 circuits plus the PV so ideally I could use all 16 50 A sensors. I have emailed Emporia to see whether they can replace it or whether I should go via Amazon. I suspect it will be fixed without issue. Anyway overall a good product and very good support. Aimed primarily at the US & Canada but it's working well for us. I can now see how much of our PV generation we are actually using minute by minute, and how much we are giving to the grid. This will help us decide whether batteries would pay for themselves. Edited August 20, 2022 by Benpointer Link to comment Share on other sites More sharing options...
Benpointer Posted August 20, 2022 Author Share Posted August 20, 2022 Ah, and... Our Ecodan 8.5kw ASHP is using 27 watts on standby, which I am ok with tbh. Link to comment Share on other sites More sharing options...
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