Challenger Electricity Supplier - Octopus and their Agile tariff

I think I'd prefer to act on pulled data rather than have to send my usage via a 'smart' meter every 30 minutes, so on that basis sounds like a good option. Time of use tariffs are I think one of the main intents of the disingenuous smart meter campaign. All I still see in promotional material is emphasis on how these meters will result in huge reductions in energy consumption, even after results from not unbiased utilities have shown an effect of something like 2% at best. I'd feel more inclined to fit one if the campaign simply came clean about the real intents, oh and after I felt that the meters themselves were beyond the 'minimum viable product' stage. Also, I think that although the nobler aim of TOU tariffs is to improve supply balancing, past experience would suggest that these will likely be utilised to try and obfuscate price comparison. But I doubt we'll have much choice in the end anyway, sigh..

I can't argue with any of the points you have made Karam. The idea of Smart meters making billing more accurate and homeowners aware of the power they are consuming at any given point is good. However, the way this has been sold to the populous as a huge benefit and the overall implementation is a disaster. Octopus alude to these issues in a couple of blog posts from February and April of this year. The original Smart meters, refered to as SMETS1, are now not so Smart and if you change supplier likely become dumb, only SMETS2 meters count as smart - you couldn't make this up!

Octopus currently have two tariffs of interest to me as a geek and EV hybrid owner. The Agile tariff which I described in my initial post as following the wholesale price of electricity and the Go tariff. Octopus Go is simpler and is aimed at Electric Vehicel owners, for four hours between 00:30 and 04:30 the cost of electricity is 5p/kwh. They have also partnered with MyEnergi who produce a smart charger, Zappi, so that your car will only charge during this period unless you override the setting becuase you need to charge sooner.

How this all pans out will be interesting, as you say it will make comparisons harder. In this respect we need to be able to plot our own consumption against mulitple tariffs rather than just the headline peak figure. I also charged to Octopus because they are a challenger, they have a bias towards renewables and they achieved top position from Which? review of energy suppliers.

Paul

Someone has created a site which connects to the Octopus API to pull both historical data and the upcoming cost of electricity for the next 24 hours (16:00 to 16:00) - https://www.energy-stats.uk/ It would be trivial to pull this data into Cortex using the REST configuration already available.

The cheapest time to use electricity is without too much surprise early in the morning where the cost is around 3p/KWH, the time you don't want to be using it is in the early evening where it can go over 25p/KWH. I have been invited to participate in a government-backed trial between Octopus & PowerVault (UK Li-Po battery storage supplier) the idea is to supplement my own solar generation with cheap electricity in the early hours and consume during the evening. Already people have come up with a phrase for this which is "charge cheap, use peak" - the benefit to the grid would be a flattening of demand to iron out peaks and troughs. With home automation this could be taken further whereby devices are turned off during peak times and things like dishwashers, washing machines, tumble dryers are set to start in the early hours. It'll be interesting to see how this panes out

Paul

interesting ...

we already do run our dishwasher in the early hours ... Cortex starts it a few hours after we've gone to bed - ie: a few hours after we tell Cortex we've called it a day, please sort everything to whatever's appropriate - cancel scenes, lights off, MVHR trickle, doors & gates, secure, UFH ... whatever ...

Chris

the point about flattening demand, etc ... noticed recently that in Germany East & West, rather than South, alignment of solar panels is being encouraged, for just that reason ... well, supply & demand ...

Chris

Chris,

How do you do this with the dishwasher does it have an API? Our dishwasher, if turned off, would restart but not start a cycle, same goes for the washing machine. I've noticed that Bosch now have Home Connect which as well as providing an app has a documented API which could be used with Cortex.

Paul

Westerly arrays in the Northen hemisphere make so much sense. Our house has Easterly and Westerly aspects to the roof, the biggest area being to the East where I have 12 panels. I soon noticed, not too surprisingly, that we weren't making the most of the electricity we were generating and with negligible FITs export price it was being wasted. Adding a smaller Easterly array last year has made a significant difference as in the summer we can generate around 1KW on a sunny day up until 19:00 rather than 16:00 with just the Easterly, this is the time you need generation most.

The following is the output of a script I've written to query the wholesale price of electricity updated daily at ~16:00 in essence Octopus Agile uses this pricing plus 2p and a cap of 30p per KWh. As you can see, in this example for 07-08/10/2019, the cost of electricity in the early hours is minuscule reaching a low of 3.70p / KWh the cost in the late afternoon / early evening is huge, rising to a maximum of 25.54p/KWh. With a battery there is nothing stopping you charging at low rates and discharging to the grid at high rates, you will make a small profit if you are on the Octopus Agile Consumption and Export tariffs. Though the profit won't justify the cost of the battery for about 25 years. However, it is an indication of how the grid is going with the increasing number of plug-in electric vehicles. Quite how the average Joe/Josephine on the street is going to work this out is @Karam's point earlier in the thread, but those willing to research and learn may have a significant advantage going forward to reduce their energy bills.

OctopusTariff.jpg

Paul

ours pre-dates things like API on dishwashers - 'though, having said that, many years ago, Siemens did offer appliances with EIB (now KNX) interfaces ...

would be interesting to see what the API offered / allowed, because that EIB interface was too limited ... temperatures, doors, on & off, etc ...

we had the top off our dishwasher (Miele) to see what we needed to do ... but experiments showed it remembered where it was after power was cut, and would resume where it left off ... so we just used a DRH module to turn power on & off, and the usual logic objects in Cortex to do that sensibly & conveniently ...

point being that it's all too easy to get things wrong with a dishwasher - door not closed properly, rotating arms clouting plates, items dislodged, etc ...

meaning our scheme is to press a button on the wall (QBI, DRB, whatever), dishwasher is powered-up, we set it running & it runs for 20s, allowing us to confirm all's alright, after which dishwasher powered-down, and brought on again at an appropriate time ... the button presses having indicated what we wanted - run immediately, run in twenty minutes (allows us time to go get something we forgot, but ensures it still runs when we fail to come back with whatever it was, having been distracted), run when house becomes unoccupied, run two hours after NighNight, whatever ...

this is all way beyond what most people imagine when they talk Home Automation ...

btw, noticed these short videos ...



how many years ago did Idratek enable the sort of things they talk about ... it was a long long time ago !

wonder how they implemented the variations of the blinds - the solar following part of it ?

Chris

good luck with the tariff games ...

we had a look at solar-PV & batteries recently ... PV efficiencies continue to rise, with a lot of the gains coming from the wiring & management side of things ... we were quite tempted, until we looked at the cost of batteries ... costs are coming down, but they still seem to be well into deal-breaker territory ...

Chris

I get what you are saying about batteries and I accept that I am an early adopter and won't get back the money I've spent; to me, it is a hobby, an exploration of what is possible and may come in the future.

The PowerVault battery has a schedule and five settings:
- Force Charge
- Only Charge
- Normal (charge when producing excess power from PV, discharge when solar is insufficient)
- Only Discharge
- Force Discharge

On a daily basis, I can alter the schedule to force charging when the price per unit of electricity is low (normally below 6p per KWh wholesale) then only discharge when the cost of electricity per unit is high (normally above 10p per KWh wholesale). If it is a sunny or light cloudy day then I can set it to normal, whereby the battery will charge when excess electricity is produced (rather than export to the grid and earn next to nothing), but if I turn on the kettle, the washing machine is heating water, etc. the battery will discharge over and above what the PV array is generating, avoiding importing from the grid. Having the ability to set a schedule changes the dynamics of the return on investment, but I'm under no illusion that over 20 years I'll make a loss.

The downside at the moment is the PowerVault schedule and setting are all all manual. I can see from the web page, using browser dev tools, that they have an API but it is private, undocumented and requires an API key that is generated from authentication. I am hoping that they open up the API in the future. At that point Idratek and Cortex would come into its own; being able to turn things on and off depending on the cost of electricity would be fantastic. If the cost per unit is low or the battery has capacity then appliances come on, but when the cost is high or the battery is low/needs to charge then the load is reduced to essential baseline.

I see this as an experiment and fascinating. It would mean that we could really move to renewables which suffer from unpredictability, smooth the electricity demand across the day and have really smart, grid-connected homes. But at the same time, it is frustrating because I can't see this happening for the masses.

Paul

Paul - compeletely with you ... interesting, what you’re doing, too ...

have read through the PowerVault spec’ etc - the optional WiFi / Internet box is enticing (thinking of Cortex) ... then again, several options are said to be not-yet available / arriving soon, and that one’s mentioned only in a diagram ...

one thing caught me by surprise ... for PowerVault3 the max’ allowed humidity is said to be 60% ... that seems very low ! When I checked Cortex here, to see where we could put one in our house, it told me the RH in our main living rooms was around 65%, in our garage & basement around 75% ... only in Node0 with its 24/7 PC was it usefully below 60% - but there’s no space to spare there !

experiments ... why not contact PowerValut about being given access in aid of developments - they might well respond positively, and give you what you need to get Cortex doing its bit ...

we’re into experiments, too - our self-build is one big one ... on the solar side of things we went with solar thermal, using Cortex to make it more effective ... solar-thermal is headlined as being 90% efficient, six times better than solar-PV ... in reality, of course, that ignores some practical details - mostly heat-losses from pipework & thermal stores ... our rooftop manifolds had begun to leak, too, so last year my brother was up on the roof rebuilding them ...

of course, something similar could be said of solar-PV - practical details like the effects of dust & leaves, losses from the way they are wired & controlled, and inverter life-expectancy ...

matching supply to demand is an issue for both, too ...

we left room on our roof for solar-PV, and ran cables in the loft ready for the inverter / controller ... we held back from installing them, but every now & then we have a look to see how they’ve improved, to see if now is the time for us ...

recent developments do look promising, so we’ve been reading-up on what’s now available ... lots of factors to consider, and the list of new developments is surprisingly long ... efficiencies are up from the 15% most people have, to almost double that ... along with greater effectiveness through more of the day, and coping better with things like dust & leaves, which can be surprisngly detrimental ...

one thing that came out strongly, was the need to view things holistically - individual ideas & technologies can all-too-easily be significantly offset by other factors & particular site characteristics ... especially when shadows are involved ...

keeping panels from getting too warm seems to be more than helpful, too, and there seem to be a number of ways of helping with that ...

PVT vacuum tubes look very tempting - 80% efficient, 20% in electric, 60% in heat, and they look attractive ...

batteries look to be almost a necessity, with lots of positive developments since last we looked ...

Standing back, though, do wonder about all this - the greenhouse effect is vital to our existence, we’d be dead without it, and our contribtion to it is only about 6% of the total - do we really understand how it works & what we can do, and do we really have the technologies needed - maybe we will make things worse rather than better ?