Charging up your home?

I do similar, but slightly more automated. I load the dishwasher, set it to run a cycle and close the door.

A load-detecting smart-plug is linked by its Kasa account to the Reactive Energy service. When the dishwasher is loaded, switched on for a cycle and the door closed, the cycle starts and creates an electric load which the smart-plug detects. The Kasa account reports it is in use to the Reactive Energy service which then switches off the plug. When the cheapest 2-hour slot is reached, the Reactive Energy service switches the smart-plug on and the dishwasher cycle continues.


I was using the Agile Octopus tariff when I first started using the RE service. Since then, I’ve switched to Octpus Go - but the RE service also allows rules too (not just smart ToU switching), so because I now have cheap(er) electricity from 00:30 to 04:30, I set the following rules in the RE service:

It works a treat, but as @Dan5 mentioned above, the human error aspect (not closing the door) is the weakest link!


cc @davidwalton

this is not as easy to do with my dishwasher, it’s an integrated unit, and so getting out to get to the plug means … well, un-integrating it :joy: Which I’d rather not do. Also, I’d have to work out if it was feasible to do in the first place.

I think I just need to move house! :eyes:

It must be the kids then :smile: - our 4 person semi-detached averages 28kWh per day, although the ASHP/AirCon has heavy use throughout the year, especially with me mostly working from home.

Unless it’s those flippin :christmas_tree: lights…

The fight to pay less for utilities against the inevitable increases continues :muscle:


I’m addicted to tracking everything in Google sheets. So those graphs are all from my mega life tracker spreadsheet.

I get the electric usage stats from an app called “octopus watch” which allows me to download the raw half hourly readings from my smart meter as a CSV.

I export the raw solar data from the solax web dashboard that came with my solar inverter.

And I have a bunch of formula that take all that data and work out costs per day/week/month/quarter/year etc.


Ah well that makes sense. If we were to factor in our gas heating into our kWh usage then our total usage ranges between 10kWh per day in the summer to around 70kWh per day in the winter. I guess the differences are that gas is much cheaper per kWh than electricity and an ASHP is more efficient than a gas boiler. So cost wise it probably means my bills remain lower than yours.

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I’m getting more into this idea.

A 5.5kwh battery would serve about 90% of my needs, I estimate (I only have monthly usage to look at though) and save me over £500 / year,

Looking at this Tesla 6.3kWh Modules | 22.8V | 252Ah - Tested Used EV Modules

If I can get that to work, that pays the battery back in just two and a half years. I don’t know the ins and outs of using an old car battery yet, but I have a very good electrician who I think might be able to sort it out. Going to do some more maths and then maybe send an email

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It seems to be. However, it isn’t enough to heat the whole house thoroughly and we also have a gas boiler which primarily heats the hot water and the upstairs radiators (downstairs radiators now turned off), plus a gas hob, so if I factor in the gas use then I’ll be at about 35-45kWh per day. This obviously drops rapidly in summer though - we’re all at peak energy use at the mo!

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Yeah I’ve heard similar from friends that have heat pumps. They are more efficient than gas boilers in terms of how much heat you get for how many kWhs of electricity they use, but their max output usually isn’t too great.

It’s tempting, but if you’re thinking used Tesla batteries you’re probably going to need some kind of custom battery management system (BMS) to safely manage the output plus an inverter. By the time you’ve bought those addition components and paid you’re electrician friend for their time and paid to have it all certified so that it can connect to the grid, you’re going to be approaching the cost of a cheap GivEnergy or moixa battery with installation.


I was just looking at other ways I can potentially change up how the house is powered.

Found this new hot water tank which appears to be able to be controlled by app, heats top to bottom in 10% points, and can toggle between gas, electric, etc sources.

The other is this phase change thermal heat battery by Sunamp. Didn’t know this existed!

Customer review and a bit of explanation

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Fully Charged (the Youtube channel) did a series earlier this year on Home Energy options. If you haven’t watched through them, might be worth a view. They did sum up quite a lot of options both new ideas being developed now, and more mature options.


Noticed this today which isn’t cool :face_with_raised_eyebrow:

Previous screenshot above

Martin Lewis saying 50% increase very likely.


This email has now gone out. TL;DR for most people: Do Nothing.

The longer story is that some people in an edge case scenario may be able to save.

Here’s a direct link to the segment of the email.