Using off-peak and solar, controlling when major users of electric start.

[ericmark]

There are three major users of electric which I can set a delayed start, the dishwasher, tumble dryer, and washing machine, all will fail to start if the power is cut, so one has to use the built in timers.

Both the washing machine and the tumble dryer will turn their drum every so often before the cycle starts, this means can't put the detergent in the drum, as the concentrate would be poured onto the clothes. And it also means it is using some, although not that much power, while waiting for the start time.

I can't understand why the drum turns while waiting for the start time. I could see why after completed, to stop creasing, but why before it starts?

 

[foxhole]

Turns to even out any imbalances, detergent placed in the drum before the clothes would have no contact with clothes till water raises the level.

 

[JohnD]

The dishwasher and washing machine do not use much electricity, except during the heating cycle, which lasts about 10minutes at 2.5kW

 

[flameport]

There are three major users of electric which I can set a delayed start,

You don't need to use any delayed start feature.

You have batteries and solar.
Either run those devices during the day when solar power is available, or at any other time from the batteries.

The whole point of batteries is to store cheap energy for use when it's convenient to use - not to mess around with timers and other nonsense in an attempt to match the time of usage with the time that cheap electricity is available.

 

[ericmark]

The point of the batteries is:-
1) To smooth out the solar supply, so not continually swapping from import to export, it maintains the supply when a cloud comes over.
2) Store the off-peak supply to bridge the gap between off peak ending and the sun coming up.
3) Extend the time when using solar generated power in the evening.
4) Provide some UPS for essential equipment.
But at just 3.2 kWh they will not allow 24/7 running off the solar supply, specially in winter, this shows

how in December no day did solar production equal or exceed our use, since December we have had a smart meter installed and off peak supply, so we can charge the battery with off peak but typically use around 10 to16 kWh per day, so when solar is low, the more that uses the off peak supply direct, the better.

In the old days timers were powered by small motors, and one could switch the power feeding the devices, so when the White meter turned on we had immersion heaters etc switch on.

For me the immersion simply not used in winter, as can't turn the DHW off when central heating is running, immersion only used in summer, but the dish washer, washing machine, and tumble drier can all be simply set with a start delay, the dish washer no problem, will set at around 6 pm, and we will continue to load it through the evening, making sure to close the door, and in the morning we unload it, during winter months, but the clothes machines both do a tumble every so often, so the latter we wait before setting timer, the better.

However after wife has sorted washing, we have 5 Ikea boxes full with different colours of washing, all waiting to be washed, after around 3 pm even in summer, it is unlikely the dryer will complete before the sun has stopped recharging batteries, the washing machine cut off around 4:30 pm as it does not take as long, so using the timers, in the morning I can resume while sun is shining.

The system works well, but waiting to before I go to bed to set timers, I often forget, and it just annoys me to hear the machines tumble the clothes through the night every hour or so, until the start time, specially as I can't see why they do it.

So any idea why they tumble the clothes while waiting to start?

 

[JohnD]

So any idea why they tumble the clothes while waiting to start?

My solar panels don't generate significant power until 9.30

So I use my thumb to press the on button on the tumble drier

No need for a timer.

 

[ericmark]

I no nothing about the Cook Islands, or how power is charged for, the idea many years ago was to use the grid as ones battery, export when access solar and import when not enough, but to do that, the export and import tariff would need to match, and they don't, at the moment not paid for export, but I likely will get paid soon, and likely I will have three tariffs. In the main it means we have three costs, we have to consider using power instead of exporting is still a cost.

This has messed up some old ideas, although my Iboost+ seems a good idea so I only heat my domestic hot water when I have surplus power, since I will likely be paid more for export to what I will pay for off peak, a simple timer on my immersion heater would work out cheaper to the iboost+.

But when trying to work out who to go with, there are so many options, British Gas seemed A1 for me, but after 4 months trying to get the payment for export sorted, I have realised they give false promises, they got me to agree to an EV tariff with a £75 exist clause, with the carrot of high export payment, but one simply never gets it.

Others like Octopus will not give an EV tariff unless you have an actual EV and charging point.

The standard tariff may be easy to compare prices company to company, but the off peak tariffs vary a lot, it seems to be dependent on how long the off peak is offered for, 5, 7, 10 hours etc. And it will depend on how you use the off peak, which works out best, clearly with off peak storage heaters 5 hours would be too short, even some users of EV cars that may not help, 7 kW x 5 hours = 35 kWh so if your trips with an EV use more than that, it would not suit. We are told between 3 to 4 miles per kWh so if you travel more than 100 miles per day on a regular basis then 5 hours would not be enough.

I went to a funeral yesterday Mid Wales to North Wales and back, did not think we were going that far, but Daughter clocked 216 miles, one simply does not realise how far we travel. Our trip to St Austell or Jarrow we know are going to be long trips, but in Wales we have to go around the hills, so we can easy put a load of miles on the clock.

So I would think 5 hours is likely a little too short for most.

However since I don't have an EV (unless you count the e-bike and mobility scooter) what matters to me, is not so much how long the off peak is, but when it starts, the state of charge as the evening progresses is what matters View attachment 351611 that purple line shows how much battery is left, in the morning View attachment 351612 we have a dip, but rare it hits 10% where we start to use grid power, it is the evening where we need to watch. I considered a second battery, that would clearly help, but they are not cheap, and the maths seems to show it would not pay for its self based on a 7 year life.

 

[Why Not Indeed]

if your trips with an EV use more than that, it would not suit. We are told between 3 to 4 miles per kWh so if you travel more than 100 miles per day on a regular basis then 5 hours would not be enough.

"enough" for what? You're not going to be unable to charge your car just because the discount rate doesn't cover your entire charging needs. It just means you will pay a bit more. In other words, the difference is so marginal that you're not going to use it as the basis for decision making.

 

[ericmark]

It seems EV charging tariffs vary between providers, mine is 5 hours, some are 7 hours, I need 1.5 hours to recharge the house batteries, the longest power user is the tumble drier at around 2.5 hours, but the state of charge in the morning rarely dips to under 10% so it would not matter if the drier discharged the battery a bit.

It is the evening where I run out of battery, not much I can do about that.

The auto use of energy, be it to heat the home, charge a home battery, or a vehicle battery depends on what the automation will allow to be set, and how easy it is to set. Early white meter with Economy 7 the user had little control, as time when on we got boost features. Even today my iboost+ that controls when the domestic hot water (DHW) is heated, has a boost function, but since I don't realise I will need it until too late, rarely in fact has never been used.

 

[omega015]

Thinking slightly differently, instead of using the inbuilt timers on the appliances could you perhaps use something like a switchbot to press the start button at a predetermined time (or based on some other logic). You have to manually setup each appliance anyway so I assume a robot just pressing the start button for you should be ok? They're not the nicest things to be attached to appliances but they are fairly small.

 

[ericmark]

Can't see it working, to start drier need to turn to off, then back to cycle required, however an interesting idea.

Cheap enough, 77p it says, but still leaves me with the when problem.

Today nearly midday and the battery is 52% charged, two days ago at same time exporting 5 kW.

Considering second battery, typical run out of power around 11 pm can be as early as 4 pm in winter, or still have 15% left in height of summer, but from end of solar to running out around 5 hours, second battery would double this, maybe more as stop at 10% to leave some for UPS, could drop to 5% with second battery.

But the main thing, it would not matter so much if appliances used at the wrong times. I have suggested to wife cooked meal at midday instead of evening, but it falls on deaf ears. And today only 800 watt, so may not charge battery anyway, so it is the off peak which makes the system work as a whole.

 

[JohnD]

. I have suggested to wife cooked meal at midday instead of evening, but it falls on deaf ears.

The cooker is not a big user of energy.

 

[omega015]

Ah thats a shame, my dryer/washing machine has a dial but I have to press the START button so I could turn the dial to the setting I want to use (Wash or dry etc..) leave it like that without starting the cycle. Then at a set point the robot would press the start button (actually needs to press it twice because the display/chosen cycle times out).

 

[Harry Bloomfield]

Cheap enough, 77p it says, but still leaves me with the when problem.

Where are they 77p?

 

[omega015]

Switchbots are about £20 where I've seen them.