Author Archives: Greening Me

Assault and battery

Like many households we actively embrace recycling sorting our routine household waste into (i) garden and kitchen waste (i.e. uneaten food), (ii) glass (jars, bottles etc), (iii) other recyclables (paper, card, tins, some plastics) and (iv) non-recyclables. Other sorts of waste can be returned to the recycling centre including (I) electrical and electronic (WEEE), (ii) batteries, (iii) used oil and (iv) wood. This post concerns batteries.

The 3Rs: Reuse, Reduce and Recycle

Like many households with small children we have many batteries in use in toys as well as in items like TV remote controls, burglar alarm sensors, and the doorbell. However we also have dozens in smart home devices like radiator valves and sensors including window, movement and environmental. Of the 3Rs of Reuse, Reduce and Recycle we are clearly far from Reduce.

Recycle is clearly possible with many supermarkets adding bins to collect used alkaline batteries which at least prevents that material going to landfill, but does involve energy and other inputs for recycling.

The alternative that I’ve been exploring for some time is Reuse. The closure of the Maplin chain in early 2018 prompted me to acquire some discount Nickel Metal Hydride (NiMH) batteries in both AA and AAA sizes and a suitable charger from my local store’s clearance sale. These batteries are the same size as the mostly commonly used alkaline batteries but have a slightly lower voltage being 1.2 Volts rather than 1.5 Volts.

Different battery sizes compared

I’ve been running these NiMH cells of AA size in Eve smart home devices for two and a half years gradually replacing alkaline batteries as they became exhausted. My only issue has been that the low battery warnings on the Eve devices are almost always set as the batteries have a lower voltage even when full, enough though the batteries have plenty of power to run the device. One thus cannot rely on the low battery warning to flag the need to change the batteries, and so I have adopted a pattern of swapping freshly recharged batteries for part-discharged batteries on a quarterly basis. Over the first weekend of the first quarter I work my way around the house room by room swapping and recharging batteries.

After two and a half years I’ve acquired multiple types of rechargeable NiMH batteries from different brands or of different capacities. I make a habit of charging and using only like cells together.

So far I’ve had no failures of rechargeable batteries.

The latest change is that I managed to locate a rechargeable replacement for the 1/2AA non-rechargeable lithium batteries used in the door/window sensors. These 1/2AA batteries are half the length of a regular AA battery, but are 3.7 Volts rather than the 1.5 Volts of an alkaline cell. The voltage of these rechargeable cells is the same as the standard non-rechargeable equivalents so hopefully the near-continuous low voltage warnings can be avoided.

Next time a door or window sensor battery requires changing I’ll be able to put these to the test.

Tapping the Admiral

I was recently amused to see a smart home feature in a television advertisement for Admiral Insurance. In that advertisement George the householder meets The Admiral outside the local bistro and, as the day is set to be warm, decides to turn down his smart heating from his smart phone.

George and The Admiral

Unfortunately George manages to hit the wrong button on his smartphone and instead of turning off the heating manages to open the garage door.

An unfortunate chain of events

The opening garage door hits George’s red car, which hits the yellow car, and pushes down the boundary wall onto the road. George witnesses all this as it turns out that the bistro is on the opposite side of the road to his home, so has a go with another button.

Sprinklers on

George’s second attempt at adjusting the heating is no more successful as he manages to turn the fire sprinklers on which floods the house. Hopefully George has more than just multi-car Insurance.

So, besides amusement, what else might we gain from George’s issues?

  1. Firstly, I’ll observe that in my home you can put the whole heating system into summer which disables heating completely (such as in the summer), or vacation which disables the schedules but which continues to heat as necessary to maintain a minimum temperature (such as winter frost protection), or turn off the radiators in individual rooms, or turn down the temperature until such time as the schedule turns them back up.
  2. You don’t always get many characters to label a device or scene, but it does need to be clear what function will be achieved by pushing the button. (I find rules particularly frustrating in the Apple Home app as you can’t name rules and it becomes hard to distinguish between them, although Eve’s app which edits the same rules does allow naming and is much clearer for programming rules generally. The WIFIPLUG app also allows the button to be customised with a photograph of the appliance which is quite neat.)
  3. Devices like garage door openers can be linked to safety interlocks. I don’t have one myself but you can have a light beam, for example, across the doorway so you can’t close the door when obstructed by a car. I haven’t come across an interlock which ensures that the car is far enough from the door to allow opening, although in reality I think that a domestic car door opener would likely stop when it touched the car, detect an over torque / current condition, and then automatically reverse.
  4. Finally I think that smart home systems would benefit from a configurable ‘Are you sure?’ question to double-check that the user really wanted to perform some potentially damaging action such as open or unlock a door.
Click to play the advertisement

(Tapping the Admiral is a nautical expression referring to being prepared to drink anything alcoholic rather than be without a drink, notably including drinking the contents of the barrel in which the body of a recently deceased and pickled admiral was being carried.)

Leading the charge

Regular readers will know that my Energy Smart home includes a storage battery. That battery is either charged from my solar panels (effectively free electricity), or low cost electricity bought from the grid, or some combination of the two depending on the solar forecast for the day ahead.

The logic of how much battery charging is required has until now been driven by a set value for the number of charging hours required. The number of hours of solar charging predicted is deducted from the the number of charging hours required to calculate the number of bought charging hours required outside the solar production window.

Bought charging hours required :=

Total hours required – Solar hours predicted

However with experience this appears to be a sub-optimal arrangement. At one extreme on a very sunny day the battery will fully charge and then be allowed to discharge continuously through all other hours, there is no middle ground in which the battery is not permitted to discharge through the night. However at the other extreme if the battery is replenished entirely from the grid then there will be hours when discharge is not permitted since, after accounting for cycle efficiency, the value of the electricity in the battery is higher than the cost of that from the grid and thus it’s better value to use grid electricity than stored electricity. As there are fewer discharging hours then fewer hours of charging will be required to refill. Thus the depth of discharge is greater when charged from solar than from the grid requiring more charging hours to refill. Leaving the longer charge time for a full charge in use then creates a risk of charging the battery when the grid price is higher than necessary leaving the battery possibly full by the time the lowest cost grid energy is available. Having a more accurate target for the charge time would enable the lowest cost charging periods to be selected more precisely.

Schedule with some solar

The new refinement is to automatically adjust the bought charging hours between two existing user-defined values: the existing target hours and the maximum charging hours currently used just to cap charging hours during plunge pricing events (i.e those with negative cost events). The new algorithm can adjust to any value between the two limits in half hour intervals. As currently configured that’s anything between five and seven hours. The new algorithm is:

Total hours required := minimum (Maximum hours from plunge,
maximum (Target hours, Solar hours predicted + 1))

max hours (A)Target hours (B)Solar hours (C)C + 1Max (B, c+1)Min (A, Max(B, C+1))
7.05.0>= 6.5>= 7.5>= 7.57.0
7.05.06.07.07.07.0
7.05.05.56.56.56.5
7.05.05.06.06.06.0
7.05.04.55.55.55.5
7.05.04.05.05.05.0
7.05.0<= 3.5<= 4.55.05.0
Output of new algorithm,

Too smart by half

One of the challenges in the smart home world is to distinguish between a group of functions associated with remote control of devices in the home for aesthetic or convenience reasons versus automation associated with the management of electricity costs, carbon management, or smart grid integration. I thus choose to differentiate using the terms Smart Home and Energy Smart.

Smart Home and Energy Smart

Smart Home

Functions within my Smart Home space include:

Space heating. In many homes space heating is controlled by a central thermostat and timer, possibly in combination with Thermostatic Radiator Valves (TRVs). In my home thermostats and timers are commonly pushed down to room level with individual rooms set points and schedules. General advice to reduce heating costs is to reduce heat loss through insulation and lower temperature set points, which I have but also add only heating rooms in which heat is required.

Window management. On occasions household members were known to go out leaving windows open. We now monitor the most commonly left open windows (plus the garage door) and use their status to illuminate and colour a smart bulb in the hall near the burglar alarm panel. The same window sensors can also be used to disable heating in rooms while the window is open.

Lighting control. We automate dusk-to-dawn external and internal lighting by the front door and in the downstairs hall. There’s overlap in bulbs between Window Management and Lighting Control.

Watchdog. To improve the robustness of all the rules operating the above functions, I have a smart plug that cycles on and off automatically at regular intervals and is used to trigger re-evaluation of the rules.

Energy Smart

Energy Smart functions include:

Battery Storage. Storing surplus output from my solar panels for later use, or buying energy from the grid when the price is low to avoid buying later when the price is higher.

Car charging. Managing my car charger to absorb surplus solar energy or buy energy from the grid when most cost-effective.

Water heating. Managing my car charger similarly.

Both Smart Home and Energy Smart

Wet goods. Controlling dishwasher and washing machine for lowest energy cost at the boundary of Smart Home and Energy Smart in both the Apple HomeKit ecosystem and with API integration for HEMS.

The Smart Home group of devices is managed via various user-friendly interfaces within apps like Apple’s Home or the Eve app where rules can be created of the form if {any trigger(s)} and {all conditions} then set {scene(s)}. These are processed by a hub which in my case is an Apple TV (or two).

On the other hand the Energy Smart devices are managed via the HEMS and are controlled by more fundamental programs (strictly in my case scripts) which are executed on my HEMS (which is based on a Raspberry Pi with HEMS-specific programming of my own creation.

In summary then, the Apple HomeKit ecosystem provides a smart home environment with a comparatively wide variety of supported devices managed from Apple’s own Home app or companion apps from the device manufacturers; while the Energy Smart side is in its relative infancy and (at least as far as my integration goes) quite a lot of bespoke software.

For me the need for much bespoke software is because I had the majority of the devices first with no thought when acquired of doing a HEMS-like project. They were originally bought or developed to maximise self-consumption of the output of my solar panels, so I had to develop the software to interface to what equipment I had. However for the Apple HomeKit, having settled on Apple HomeKit largely because we were iPad users, it becomes relatively easy to add additional devices that are sold as compatible with the HomeKit ecosystem.

Works with Apple HomeKit

Getting heated

Regular readers may recall that our hot water can be generated in 3 different ways: (i) conventional gas boiler, (ii) from grid electricity and (iii) from the surplus on my own solar panels. Attractions of these options are that gas is always available and stable in price, but my grid electricity is lower carbon and may at times be cheaper than gas, and my solar electricity is lowest in both carbon and cost but is subject to significant daily and seasonal variation.

The logic to sort out which source to use is managed by my HEMS. Gas is the baseline and the gas boiler is set to heat water for an hour a day in the early evening to ensure that baths etc are possible. The heating is thermostatically controlled so it doesn’t heat if the water is already hot, and that thermostat is set slightly lower than the immersion thermostat too.

The ImmerSUN normally operates automatically to divert surplus solar electricity proportionately to the immersion heater after the needs of general house load, battery charging and car charging have been taken. However if the electricity price is negative (yes, really) then the HEMS may override the ImmerSUN so that water heating is not done by free solar but instead may be delayed to allow use of paid-to-use electricity.

The final part of this triumvirate is buying electricity from the grid to heat water. Here the price of bought electricity is compared either to the price of gas and a decision made to use electricity when it is cheaper (it’s always lower CO2), or compared to the price of surplus solar (effectively zero) to buy from the grid. Both of these are obviously comparisons with a price threshold but until now the choice of threshold has been made manually – typically against gas in winter when solar output is limited and against solar in summer when more readily available. However the reality of UK weather is that this is a compromise as it may be very sunny one day but very dull the next.

Solar forecasting

The new refinement therefore is to use the existing solar forecasting integration. Solar forecasting already informs HEMS decisions about when to charge the storage battery from the grid and when to operate the wet goods (dishwasher and washing machine). The latest change is that the solar forecasting is now also use to choose whether to base a decision to buy electricity for water heating against a threshold related to the gas price or against the price of surplus solar PV.

HEMS schedule for July 4th.

The above schedule shows that, as a result of no significant solar production anticipated on the 4th, the HEMS has compared electricity price to gas price and thus elected to buy electricity from the grid to make hot water overnight since at 1.7640 to 2.4675 p/kWh electricity is cheaper than gas.

You learn something new every day.. WIFIPLUG

Increasingly I’m starting to use Siri when loading the dishwasher, as in (i) load dishwasher, (ii) start dishwasher, (iii) “Hey Siri, turn the dishwasher off”, and (iv) allow the HEMS to resume the cycle when then cycle cost is most attractive. The dishwasher (and washing machine) are operated by WIFIPLUG smart plugs to achieve this.

WIFIPLUGs v1 and v2.

However on occasions I used WIFIPLUG’s own app to control the plugs rather than Apple’s Home app, the Eve app, or Siri.

The WIFIPLUG app used for dishwasher and washing machine control

However I have a frustration with the WIFIPLUG app that it often takes three presses to turn the dishwasher off after starting the cycle:

  1. Initially the app shows that the plug is off, although the plug is physically on – the first press reports a communications issue.
  2. The second press reports that it’s turned the plug on, although the plug was physically already on.
  3. Only the third press turns the plug off as was the original intent.

However today I discovered that the WIFIPLUG app is not supposed to reflect the live status of the plugs, instead one swipes to refresh and then presses to toggle status – so two actions in my case rather than three listed above.

I find the need to swipe to refresh completely non-intuitive as both Apple’s Home app and the Eve app show the live status of devices and there is no refresh concept, but I suppose it’s reassuring to know that the app is designed to work this way rather than being broken.

In the meantime, to the best of my knowledge, WIFIPLUG is the only smart plug not only supporting Apple’s HomeKit ecosystem, but also having an exposed API for smart home integration, making it uniquely suited to my application.

It’s official – I’m a smart home / energy pioneer :-)

It can’t be very often that an energy company blogs about its customers’ achievements. Last week it happened. Octopus Energy wrote a blog entitled “How to hack your home for cheaper, greener, energy with our open API” which featured the achievements of its customers, and Greening Me got two honourable mentions.

For those not familiar with geek-speak, API is Application Programming Interface which is a mechanism by which an app, webpage or computer program may give commands to, or receive data from, another program – often a web server. Such APIs are often closed (that is that they are only available for use by the creator’s own app or webpage etc), but in this case the Octopus APIs are open so that they can be used by others (including me) to create our own apps, webpages, or other integrations to get data from Octopus. That data may be future price information for a UK electricity region or the actual consumption from a specified electricity meter for example. Octopus document their APIs and encourage others to find innovative uses for them.

Other APIs that I use were either documented privately by the manufacturers of the equipment concerned, although the manufacturer has not put the API in the public domain, or were reverse-engineered by myself or others by looking at how the manufacturer used it or at the internet traffic that it generated and working out how we could use it ourselves for a slightly different purpose. Such purposes would include controlling equipment other than by the manufacturer’s own app, or collecting data into some non-supported form.

Diversity in third party solutions using the Octopus API.

Greening Me’s first mention in the blog came under the Smart Electric Vehicle (EV) Charging section where Octopus wrote..

One of our own smart energy pioneers, Greening Me, has used a Raspberry Pi and an add-on circuit board with our API to switch his electric car charger on/off and set the best time for his hot water immersion heater to run. He also has solar generation and so he can direct his solar power to either his smart car charger or hot water.

The first reference

Later in the “I’ll do it myself (tech level 🌶🌶🌶)” section after describing a group of “smart home pioneers” Octopus wrote..

In the home-brew category, users like GreeningMe have created their own Home Energy Management Systems (HEMS), using the ubiquitous Raspberry Pi to manage a large part of their energy consumption.

Together with Western Power Distribution, Passiv Systems have also created something similar to Greening Me’s HEMS, which is currently being trialled and evaluated as another BEIS funded research project called MADE.

The second reference

So it’s official – I’m a “smart energy pioneer” and a “smart home pioneer”. I also quite like the idea of being a “home hacker” in the positive sense of someone who makes their own home conform to their wishes. If you’d like to read the full blog post from Octopus Energy then you can do so here https://octopus.energy/blog/agile-smart-home-diy/.

Overall I’m proper chuffed.

Opportunities in the import / export business

Most of us are used to a simple world of electricity where we pay for what we consume. For most folks like myself based in the UK that’s typically a fixed price per kWh/unit consumed regardless of time of day, even through dual-rate tariffs have been around for decades – the best known being “Economy 7” tariffs. However as the grid gets smarter then there are increasing opportunities to save on, or make money from, electricity.

Electricity opportunities for import / export and positive /negative cost.

Conventional – pay for power.

This is the area with which most of us are most familiar. We all get the idea of paying for the power we consume. Most UK households pay a fixed price per kWh/unit regardless of the time of day. We have a competitive electricity market, so there are the choice of 70 to 80 different providers who will make different offers regarding standing charge (sometimes marketed as a subscription) and unit cost.

There’s also the opportunity to choose between a flat rate tariff or Economy 7 even on conventional meters that provide a discounted night rate for 7 hours.. These typically provide a discounted night rate, but may charge a little more during the day. They used to advertise these as ‘less than half-price electricity’ but that’s often not the case now.

Stepping up in complexity (and opportunity) smart meters provide the opportunity for a more diverse range of tariffs including different cheap night time periods, more than two rates at different times of day (in extreme 48 half-hourly rates), and a free day at the weekend (i.e. a zero rate of a weekend day) etc.

Beyond that my own tariff (Octopus Agile) not only has up to 48 different half-hourly prices/day that change daily based on that day’s market prices. That might sounds a bit scary but it can yield very cheap electricity prices – 4.48 p/kWh for me in April/May 2020 (for example) which is a third of what most people pay.

My electricity costs April/May 2020

(The original version of this post wrongly had the table from my gas bill above and mistakenly claimed that I had paid “a quarter of what most people pay” rather than a third. Total consumption is untypically low at the present time due to limited miles driven.)

Agile – paid to consume

Top left on my initial diagram is Agile – paid to consume.

One of the features of the wholesale electricity market is that at times the market price for electricity goes negative. At such times the a significant excess of supply (typically because of high output from wind turbines) over demand (often but not always at night) yields a negative price so electricity companies looking to buy electricity are being paid to take it. Most electricity companies will continue to charge their customers the standard price in these circumstances but, with the octopus Agile tariff, the negative pricing is passed to the consumer so that you are paid to consume electricity. This is one of the reasons that my electricity costs are so low.

My electricity costs – Saturday 23rd May 2020

The above chart shows my electricity costs for Saturday 23rd May 2020. The blue line shows the half-hourly electricity price varying between minus 10 p/kWh and plus 15 p/kWh. The red bars show my electricity consumption in each half hour. You can see how consumption tends to be highest when the price is lowest leading to an average price paid of minus 6.22 p.kWh (i.e. they paid me to use electricity) – indeed they paid me 82.4 p to buy electricity that day.

Conventional export – paid to export

The next opportunity to make money from electricity is to sell it to the grid. Obviously that depends on having a source for the electricity typically a generating asset like solar panels or a wind turbine, possibly coupled with a storage device like a battery. It’s also possible with a battery alone, but I know no-one who does that as the economics are more challenging.

The UK currently has a scheme called Smart Export Guarantee (SEG) where you can sell your export to an electricity company. Prices vary enormously so it’s worth shopping around and not just assuming that your electricity company will give you a good offer.

SEG rates from the Solar Trade Association

There is also a smarter SEG option where Octopus offer a dynamic SEG based on market rates (Octopus Agile Export) which may at times offer a high rate, but also offers a lower rate at times, and is thus perhaps better suited to those with storage.

I myself am NOT on such a tariff as I’m on an older legacy Feed-in Tariff (FiT). Despite its name FiT is a generation incentive, not an export incentive. As a generation incentive FiT encourages self-consumption since each kWh that I consume myself does not reduce my income, whereas on SEG each kWh that I use myself (such as making hot water) would reduce export income. So, for example, if I use a kWh of electricity to make hot water that’s saved a kWh (or thereabouts) of gas at around 3 p/kWh, but if I was on SEG then I might have lost 5.5 p/kWh of export revenue to save 3 p/kWh on gas which is clearly an on-cost not a saving. There are other benefits of course because I’ve reduced my carbon footprint by using my own low CO2 electricity to replace a fossil fuel, but it’s not (in this case) improving my financial position.

A further area of research by others is V2X (V2H and V2G) – taking electricity stored in an electric vehicle and using that within the home (V2H) or exporting it to the grid (V2G).

Export penalty – penalised for export

A logical consequence of this smart grid that I’ve outlined is being penalised for export. If there are times when the market price for electricity is negative then if I were part of that market then I might expect to be penalised for export. This doesn’t actually exist in the UK, as the only model that links SEG payments to the market price, Octopus Agile Export, protects its customers from negative pricing.

Should consumers be exposed to this risk then a logical behaviours would be:

  1. To manage self-consumption into the negative export periods, and potentially thus increase export in the positive export periods. For example disable diversion to an immersion heater or car when export price is positive, and then maximise self-consumption when the export price (and presumably the import price also) is negative.
  2. To disable the generating asset to avoid the export penalty.

Conclusions

Some people like myself will find developments in the smart energy sector a fascinating and engaging topic with opportunities both the save money and engage in creating a cleaner and greener electricity system.

However given that many choose not to even participate in the competitive market for electricity supply created when the regional electricity companies were privatised in late 1990 (i.e. 30 years ago) then there will be a significant number who are not so motivated.

This then creates opportunity for a wider variety of smart offers. Some products, at the Agile Octopus end of the spectrum, giving the consumer the opportunity to benefit from their own decision making, while others look more like a traditional dumb tariff with a very simple price structure but potentially making the energy company a more active manager of the home appliances so that the consumer hopefully plays a lower unit rate while the energy company takes responsibility for managing the assets within the home.

Bright revisited

Back in late 2018 I purchased a Hildebrand Glow Stick Consumer Access Device (CAD) to monitor my electricity consumption. A CAD is a consumer device that can be paired with domestic smart meters to provide the consumer with a means of reading the meter. All UK smart meters are supplied with a dedicated in-home display (IHD) to display energy consumption, which is also an example of a CAD. The Glow Stick pairs with the meters like the IHD but shares the data to the cloud from where it can be read either via an app (Bright) or another device using APIs.

Glow Stick CAD

Each smart meter effectively has two interfaces – a Wide Area Network (WAN) connection used for metering and billing and a Home Area Network (HAN) used for connection between meters (electric and gas), hub (embedded within the electric meter) and IHD. The HAN is also available for smart home devices.

“Network hub“ including Glow Stick

“Network hub” including (from top to bottom):

  1. Network switch providing additional hardwired connections to the internet, placed behind..
  2. TalkTalk router providing WiFi and 4 hardwired connections to the external internet, placed above..
  3. Network storage, placed above..
  4. Immersun bridge (left) and Glow Stick (right and forwards)

When I initially installed the Glow Stick it provided a very useful tool to see current and historic energy consumption, but the equivalent cost displays were incorrect (at no fault of Hildebrand) because the CAD correctly read the meter costs, but the meter was not sufficiently sophisticated to store the complex Agile tariff (where unit cost changes every 30 minutes).

I recently learned that Hildebrand now had the ability to take the tariff directly from Octopus Energy via API, bypassing the incorrect tariff data in the meter. A quick support email to Hildebrand confirmed that this was not only possible, but also that the cost data would be corrected back to when I bought the Glow Stick back in 2018. A few days later and the conversion was complete.

These two views show today’s part-complete data:

The screenshot on the left shows today’s part-complete energy data. That on the right shows the equivalent cost data. Had the unit rate been constant throughout the day then the two profiles would have been proportional, but instead the screenshots show the magnifying impact of the higher unit rates in the four to seven PM window with equivalent consumption to the late afternoon resulting in rather higher costs.

I should emphasise however that my average unit rate is very low as I usually have much higher consumption in low cost periods than I do in high cost periods.

My electricity bill to May 2020

One of my recent electricity bills had an average of 3.49 p/kWh ex-VAT. Half-hourly rates varied between around minus 10 p/kWh (I.e. I was paid to use electricity) to plus 25 p/kWh. A low average price was achieved by shifting electricity consumption to when the price was lowest.

My next step is likely to be to use the API to get the real time household load for load management as an increasing number of electrical consumers (potentially a second car charger) risks overloading my supply fuse if all loads were on simultaneously.

Washing away any confusion

I previously described how I had integrated the washing machine into the smart home ecosystem using a smart plug so that it is (re-)started by the HEMS when the cost to complete a washing cycle will be lowest, bearing in mind that my electricity supply is a combination of paid-for electricity where the price varies each half hour and ‘free’ solar. As the means to get the best from the combination of washing machine and smart plug has been the source of some confusion within the household then I thought I would lay out how to get the best from that combination.

Bosch Washing Machine

Starting the cycle:

  1. Normally as found the smart plug should be on having been left on following the end of the prior load, but if not then turn the plug on using either (i) the button on the plug itself, (ii) the WIFIPLUG app or (iii) the Apple Home app.
  2. Load the drum in the normal manner which is optional washing liquid tab first with colour-catcher if required and clothes on top.
  3. Select and start the required cycle.
  4. Almost immediately stop the cycle on the smart plug using the same options as in #1.
  5. Put washing powder, fabric softener and water-treatment tablet (e.g. Calgon) in the drawer as required.
  6. At the optimum time the HEMS will restart the cycle. Do NOT move the cycle selector dial on the washing machine while waiting for the cycle to restart or the washing machine may become confused.
WIFIPLUG smart plug

Adding more clothes while waiting for step #6 above:

  1. Pull the drawer forward so that any water admitted to the washing machine will not take the contents of the drawer with it.
  2. Turn on the smart plug as per step #1 in the ‘Starting the cycle’ list – our washing machine starts to fill with water at this point.
  3. On our washing machine clothes may be added during the early stages of load by pushing the start button. Washing machine briefly displays “No” and then (i) stops the water flow, (ii) unlocks the door and (iii) displays “Yes”.
  4. Extra clothes may then be added.
  5. Once the extra clothes have been added, the door can be closed, the start button is pressed and then the washing cycle will resume.
  6. Stop the cycle almost immediately with the WIFIPLUG using any of the usual options.
  7. Close the drawer.
  8. At the optimum time the HEMS will restart the cycle.
Home

Ending the cycle is absolutely unchanged versus the washing machine without smart controls. The washing cycle finishes. The WIFIPLUG is left on by the HEMS. The door can be opened and the clean clothes dispositioned appropriately in the normal manner.

The dishwasher works similarly but more simply. The door can be opened at any time while awaiting the restart instruction from the HEMS and items removed or added as required.