Hardware/software for automation?

This may be too open a question, with too many options/opinions, but here goes.

I've got a 4kW solar array, with a 9.4kWh battery.

As I'm about to switch to Octopus Agile, I was wondering what recommendations people currently have for automation, to make the most of the Agile tariff.

I'm assuming I need some dedicated hardware - if so, Raspberry Pi, Arduino, other?? Or is there a SAAS/hosted option?

And then there's which software to use.

Interested in opinions/lessons from the real world!

(I'm up for configuration/coding etc. - I'm a s/w developer by profession).

I went for Raspberry Pi and installed Home Assistant on it.
Got it all going in 1/2 day (and I am 62 and not a computer boffin)
Followed this https://www.makeuseof.com/how-to-install-and-setup-home-assistant-on-raspberry-pi-for-home-automation/#:~:text=Connect%20the%20Micro%20SD%20card%20to%20your%20system,Home%20Assistant%20OS%20image%20to%20an%20SD%20card.
And then https://www.youtube.com/watch?v=NQ84z_Wa19k&ab_channel=SpeaktotheGeek

SteveCook Great info - thank you!

James L
If you prefer a non-tinkering standalone easy option then WonderWatt seems to have a number of fans.

If you prefer to play then there are lots of choices, but the most popular seems to be Home Assistant - a large and very active open-source GitHub project. If you have an always-on machine already then you don't actually need any new hardware. Home Assistant and anything needed to support it will happily run on anything which has Docker.

That said, many people choose to start off with a Pi. Though it is pretty common to outgrow it fairly quickly, and it's not an ideal platform (with sd failure due to write exhaustion being a particular issue).

Although I am a long-standing HA user, I am new to the solar world. I would heartily recommend having a look at predbat. (This is a HA extension, which takes data from Octopus, your array, battery, meters, and an external solar forecast and then uses your historic usage patterns to actively manage your battery for you - including any DFS/Saving Sessions or Power-ups.)

PianSom Thanks - I've tried WonderWatt, but I'm not sure they take much notice of tariffs (or didn't when I was using it). Don't they only look at solar forecasts?

HA (and predbat) look a good option. I could get it going on my work mac, and then move it across to smaller dedicated hardware.

Personally, I have never tried WonderWatt

James L I could get it going on my work mac, and then move it across to smaller dedicated hardware.

Docker on OSX works. But it is a bit of a pain in the bum sometimes. FWIW for the last few years I have used an i3 NUC which is also used as a media server and generally useful Docker machine. Many people these days prefer using VMs on Proxmox or similar - easier to manage than docker-compose wrangling.

So yes, starting off on Docker on Mac is not an eccentric decision. Let us know how you get on, and if (when!) you get stuck. Good luck!

I've had panels for 13 years but just installed an AIO late November. I purchased a second hand Lenovo ThinkCentre M900 USFF PC Intel i5 from ebay for £72. Installed the HA OS on it and followed various youtube channels. Another recommendation for the SpeaktotheGeek channel for Givenergy products set up on HA. Another useful resource is the GivTCP group on Facebook. The PC just uses 8W when idle and not much more when processing - I have it connected by cable to the router.

I have Givtcp and Predbat (https://springfall2008.github.io/batpred/) working - you will need Predbat to optimise charging/discharging when on Agile. Will also need to setup a Solcast account and instal on HA. I'm still learning the drtails of how it all works and the customisation necessary to optimise my needs so expect a few weeks of learning. Suggest you run it in "Monitor" mode at least for a few days and look at the proposed plans to understand what it intends to do before switching the system live.

I'm currently using Wonder Watt and am impressed with the support and regular updates. They seem to monitor the support forums almost in real time and are keen to take onboard suggestions and tweaks.

I have Odroid N2+ with Home Assistant OS with 64gb microSD and 128GB SSD. GiveTcp through MQTT and Mosquito Broker and also Running Givennergy Local. Its not perfect because sometimes it will not change charging rate and battery will not charge. So you can wake up with battery not charged.

HipHopAst
Does you system still work ok with GivEnergy local, or can you put GivTcp on your device.
https://community.givenergy.cloud/d/3615-do-not-update-to-battery-3015-if-using-givenergy-local-in-home-assistant

James L As I'm about to switch to Octopus Agile, I was wondering what recommendations people currently have for automation, to make the most of the Agile tariff.

I'm simply using Octopus R&D and letting it choose the best agile prices within a given window I set on a fixed schedule. Works great for me (no EV no ASHP, just battery and solar), no fuss, no complicated setups, and I can set multiple extra charge windows if I want.

SteveCook I can confirm that on battery firmware 3015 GivEnergy local still working on my HA. Worth to mention that I have Gen1 Inverter and 5.2kWh battery. Inverter firmware version is D0.449-A0.449 and its 2 years old. So it looks like if your inverter firmware is old GivEnergy local will work.

HipHopAst
Thanks mine is Gen1 and works with GivEnergy local and that was how I was using it, but in case it was going to break i have pathed all my dashboards to GivTcp

SteveCook If you think this way or if one or other stop working i suggest use utility meter helper. If givenergy local stop working and you move to givtcp you automaticity loose all historical data for energy dashboard. If you setup Helper and use this entity to setup your energy dashboard every time you change from givtcp to givenergy local or if you decide to change to completely new inverter you still keep your historical data.

pacemaker That's also a good option to consider, thanks. I've used R&D previously.

James L We're currently working on implementing Octopus Agile integration, and are aiming to complete this by the end of January.

But fully understand that some people love full control and for them, HA might well be a better option.

Wonder Watt Thanks - that's good to know. I may give Wonder Watt a go (again) when you've got it going. Let me know!

pacemaker I've just moved to Agile, and I'm still trying to decide if I have just made complications for myself without any benefits (I was on a simple economy7 tariff before).
I have set myself up on the Octopus R&D site, but can't work out how to do what you suggest.

Is there a guide to how to set up and use the scheduler?

In the scheduler I can see optimisation options of "none", "Octopus" and "Carbon" and "Standard" or "Half-hour"

"None" seems to just charge at fixed times, which is great but takes a lot of setting up to do that for each day's tariff profile if I want to avoid certain times

"Octopus" sounds closer to what I want, but I can't get it to setup. The portal refuses my entry saying "charge is a required field" when the "charge if rate is lower than" switch is set. So have not been able to test how it works.

I dont understand the difference between "standard" and "half-hour"

Any insight into the above would be appreciated.

Thanks.

Using Octopus R&D charging on “x” amount of slots between 00:00 and 08:00. As we get into summer months i will be reducing the charge slots until system will run on solar only in March! Works great so far! Wish I joined Agile earlier actually!

James L What hardware do you actually have now? Got any NAS boxes for example? Anything which can be left on 24/7/365 without eating too much more power?

You can run HA/GivTCP on anything from an old Pi to a new gaming machine - just needs a Linux image/docker/VM depending on what you're using.

I wouldn't underestimate how hard it can be to source new Raspberry Pi units at times - or indeed how much new models get resold for. It might have started out with the intention of a cheap, ubiquitous device but it hasn't stayed that way over the years - at one point it was easier to get hold of top-end NVidia graphics cards than it was to buy a new Pi 🙂

Vestas Yes, I've got an old NAS box somewhere, but quite where I'm not sure. But even better, my Raspberry Pi 4 is being delivered on Wednesday! So at the moment, seems to be OK. Yes, I'd heard about the Pi shortage!

Top tip - if you know anyone who lives near Cambridge (or possibly Leeds) all Pi’s are readily available at the Pi shop

@James L, like @Ivan I bought a second hand Intel i5 tiny PC from ebay for about £70 which came with Windows 10 Pro. Installed Oracle Virtual Box and then Home Assistant (HAOS) as a virtual machine.

I followed the Speak to the Geek videos for installing GivTCP and initially wrote my own automation scripts (with lots of trial and error) to manage discharging my battery during Flux peak periods.

I knew that my battery wouldn't be big enough to support the home demand once I turned the ASHP on for the winter so would need some intelligent scheduling, and selected Predbat based on the Speak to the geek video again.

It took a while to get the hang of Predbat and understand what it was doing, but since then I felt comfortable enough to move from Flux to Agile in mid October and have been very pleased with Predbat and what it delivers for me since then.

There's an active community of help around Predbat and there's been quite a few improvements to the documentation, install process and configuration options even in just the last 4 months I've been using it.

Vestas

New Pi 5's are available on the three main seller websites I think one only carried 4GB other 8GB and one had both all in stock - allegedly

I decided to get one my old Pi 3 is creaking a little and I want to run node red and homebridge on it with possible NAS using some SSD's

James L Hi James - would you like to test our Agile Octopus integration? If you drop us a line labs@wonderwatt.com with your signup email, we can get you added to the test group before the full rollout. Cheers!

Wonder Watt Thanks - will do. Although I'll need to make a decision whether to go with Wonder Watt or HA/Predbat etc!

I'm still waiting to be switched to Agile...

James L Yeah that's fair, you can always give us a go though whilst you set up your full HA suite. Would appreciate any feedback tbh, even if you switch back to your own HA solution afterward, thank you! 😄

Wonder Watt one question for you - does WW support controlling third party smart devices? Eg turning on devices to charge when prices are cheapest, outside of the GW/GE ecosystems?

26Left Hi, it doesn't currently, but if there is a decent cloud API integration for those smart devices, and there is demand for this, we could look into coupling that with Agile Octopus for sure.

What specific use cases were you thinking of?

Wonder Watt thanks.

Perhaps this is too niche for your roadmap right now, but I think there are quite a few PHEVs out there that could benefit from “smarter” Agile charging to control their 3 pin charger via a smart plug - possibly more than there are people with solar+battery!

I currently use a Tapo / TP link smart plug to control charging at present on a timed schedule. In the winter I use Go for it’s a fixed window, but in summer I move to Agile. So each evening I pick the best window to charge the car overnight based on the day ahead rates (in parallel with my GE AIO to avoid one charging the other), and manually add charging in the afternoon if PV generation continues once solar battery is full (and the car has been driven).

Otherwise I think my options are

• get to grips with HA
• buy a IOG compatible charger - my PHEV charges in 4 hours at 13A (for 1.5p/kWh import saving, and a 10kWh PHEV battery, the payback time is unlikely in the expected lifetime of the charger).
• stick with Go all years round
• wait for GE to make their own smart plug, well, smarter…

26Left Interesting. We got some Tapo plugs as well and I'm aware they can be controlled via a cloud API.

Are they reliable for charging at 13 amps for several hours?

The worry is these APIs tend to be very much undocumented and could change at the drop of a hat, or access could be disabled by the manufacturer.

Food for thought though, thank you.

Wonder Watt Regardless of whether they're reliable or not, EV charging is specifically not supported by the manufacturer. Their statement on the link below is spurious but I suspect they mean it'll overheat if you try to fully charge an EV, rather than a PHEV.

https://www.tapo.com/uk/faq/358/

Edit - basically it looks like its rated 13A resistive and doesn't deal at all well with anything inductive. Cheap contacts probably.

Wonder Watt Are they reliable for charging at 13 amps for several hours?

So far, so good. I have been using it since June and it's proven reliable for me. I inspect it every few weeks and no signs of damage or degradation to date.

It's the P110 (energy monitoring) model, and the charger draws no more than 2200W (so c. 10A). I've never seen the car take more than 7.7kWh of charge from empty to full. It's therefore finished charging within the 4 hour block I set for it.

Wonder Watt I reverse engineered a bunch of EV charger APIs if that is of any use to you.
https://community.home-assistant.io/t/ev-charger-api-collection/378432

I kept the Ohme to myself for years as they got funny about it, however their stance has soften of late, so that is fair game too.

hoggy Awesome, thanks very much, could prove very useful! 🙏

26Left You got me thinking a bit more (ha!). Why and how would someone with a PHEV and no solar or batteries be on an agile tariff, as opposed to a more standard offpeak/peak tariff?

Wonder Watt Dunno about the PHEV part of it, but Agile (without a battery) will save you 30%(ish) compared to a standard tariff if you're at home/work from home and can avoid the 1600-1900 peak time. I know a few people who've been on it for years and have no PV/battery.

26Left Hi - would you mind dropping us a line please? labs@wonderwatt.com - thanks!

Wonder Watt have sent you an email

I haven’t run the numbers but my hunch is that with just a PHEV, charging once per day, c 10kWh is approximately equivalent to the entire house consumption for most. Therefore time shifting the charge window is significant.

Only a few utility providers offer an EV tariff. And agile for me was better value than the fixed time EV tariffs - at least over the summer.

And only so many people have a compatible car / charger combo for the “intelligent” tariffs managed by the utility companies, eg the most popular PHEV is / was the Mitsubishi Outlander. But doesn’t appear in the “supported’ lists.

Does anyone have any experience of using My Energy Optimiser with agile? The dashboard looks very slick and I’m interested in giving this a go over going down the HA route.

Capt_Rich We don’t do snazzy charts, as there are far better tools out there for that, but we do have smart schedules and Agile Octopus integration too, if you wanted a HA alternative.

Thanks. I was an early user of wonderwatt last year when I was on flux, at the time it didn’t work that well for me, but I’ve since had a second battery installed and you’ve obviously done lots more work since then so it may well be worth another look. I’m currently on an Econ 7 tariff for the winter and will go back to flux in the spring. Do you support Econ 7? I’m considering trying agile for a few months before there’s enough solar to make flux viable again

Capt_Rich We support Econ 7 simply via the regular schedules that you can set up. We've done some consolidation of the structure of the schedules (which was initially confusingly split into Smart Charging and Optimise Export menu options), but now it's all in one section and you can set up up to 5 charge or export schedules.

https://www.wonderwatt.com/multiple-schedules-smart-charging-with-growatt-and-givenergy/

Let us know if you have any questions or encounter any issues, happy to help you out.

Capt_Rich I've just switched this week from Eco 7 to Agile and so far so good. Everyday have been able to charge the batteries for much lower than the 14.5p Eco rate. It took minutes from their webpage to switch over and the rate was backdated to the previous midnight.

I think some automation to optimise the charge (and discharge) is necessary when on Agile - I've got predbat working and it's performing very well.

Ivan thanks. On the octopus agile compare page, the savings on my actual usage between Econ 7 & agile were minimal, but now having the second battery might make all the difference. As you say some level of automation is probably best with agile.

Wonder Watt I've decided to dive back in, have to say setting the schedule is now a lot more straightforward, looking forward to seeing how it will work for me this time

Capt_Rich Yes I have been using MyEO for nearly a month.
I switched to Agile on 23 Dec and got the very low prices over the Xmas period. I have 14kW ASHP and EV and used 2000kWh in the last month, saving about 50% compared to the Octo Flex tariff.
So very satisfied with Agile and MyEO. MyEO developer is very helpful and the Dashboard allows lots of fine control over charging etc.