# Is it dangerous to do a wash overnight?

Running a washing machine on a low temperature wash such as 30-40°C likely uses negligible electricity compared to the heavier loads in the household, so there's probably not much to be gained overall from running it at night on a night/off-peak unit rate
That’s a fair point. A modern washing machine uses about 0.5kWh per cycle, a dishwasher a little less than 1kWh. Depending on your tariff you might save €0.15 per kWh on the nightrate. So we’re saving €125/year by running the appliances at night. Not nothing, but not huge either.

That’s a fair point. A modern washing machine uses about 0.5kWh per cycle, a dishwasher a little less than 1kWh. Depending on your tariff you might save €0.15 per kWh on the nightrate. So we’re saving €125/year by running the appliances at night. Not nothing, but not huge either.
You must run your appliances very regularly?

That’s a fair point. A modern washing machine uses about 0.5kWh per cycle, a dishwasher a little less than 1kWh. Depending on your tariff you might save €0.15 per kWh on the nightrate. So we’re saving €125/year by running the appliances at night. Not nothing, but not huge either.
Well the savings for us using the EV rate between 2 and 5 am according to the bill I've just received is about €150 per year
That's an average of 100Kwh for a month, using the immersion for an hour and the washing and dishwasher when needed
Based on a night rate of 25.27cKwh and EV of 8.54cKwh less 25% discount plus 9% vat

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You must run your appliances very regularly?
Young kids, so two dishwashers and one washing machine every day

IF I was to run my washing machine at off peak hours and I run it 3 times a week as normal, works out at 78KwHr, assuming .5kw hr.. Assuming a saving of 20cent which is on the higher end, its 15.6 euro a year. In reality, I'd run it at 7am when I'm getting up, which looking up appears to be the off peak rate (not EV rates). I don't have a dishwasher/drier. I'd still make changes to immersion / heat pump.

It boils down to, is the small added risk worth the 1-15 Euro a month? Bigger the family (or at least the greater the number of appliances) the greater the saving, closer to 1 euro a month for me.

I've had to evacuate a hotel at about 2-3 in the morning with a toddler because of a fire alarm - not fun! Different for just adults, but even with just adults in house not worth the small increase in risk for the price of up to 1 cup of coffee a week (more like 1 a quarter for me!).

It boils down to, is the small added risk worth the 1-15 Euro a month?
I think for us it's more about the perceived risk rather then the money saving exercise
Long before we got smart meters we've been putting the dishwasher and washing machine on simply because of our routines and lifestyle
Mrs C is a night owl and puts both on before she goes to bed and as I'm an early bird I empty and hangout the dishes and clothes
I don't in any shape or form perceive this as a risk to our lives but maybe if we had kids and a normal routine, I might think differently

The added bonus of the smart meters is we can now avail of cheaper electricity plans to run these appliances, so if they suit your lifestyle and routines why wouldn't you make the most of them??

The added bonus of the smart meters is we can now avail of cheaper electricity plans to run these appliances, so if they suit your lifestyle and routines why wouldn't you make the most of them??

Of course I would, I used to have a day and night meter, I'd often be up at 6-7am and would turn on a wash and take make use of it, or similarly I'd be up till 12pm, and would turn on a wash at 11pm when I knew the rate switched over. However, I would not be setting timers to have a wash come on at 3am to make use of the EV rate when I'm out cold in bed.

I was randomly discussing smart plans this morning (friend was getting a new EV car). One of the others piped up with, just don't use the washing machine when asleep, her brothers washing machine went on fire when they were in bed. My small anecdotal data is 3 people I know had machines go on fire. But only my anecdotal data, clearly we all get to decide risk for ourselves - I'd just point out if doing it for money saving, is what you're saving worth the difference in risk.

How many people do you know whose washing machine did not go on fire?

Probably hundreds, if not thousands

I can't find statistics on this but I find it worrying that lap-tops continue to be used in beds and on top of soft furnishings. Laptops have fans that draw in air to cool components when they are in use. In scenarios where there is dust, lint, dried skin, fluff, hair, etc in the surrounding environment, these will be drawn in and can block the cooling pathways or even the fan itself.

My first suggestion is not to use laptops in this way and the second, as a regular maintenance step with the laptop powered off, is to vacuum clean the fan intake port (usually a grille on the side or bottom of the chassis).

Check leads and transformers (the block in the middle of the mains lead) for cracks or damage and change any that don't look up to snuff. Also, my pet hate in these devices is the 13 amp fuse in the mains plug. Ditch and replace it with a 3 or 5 amp fuse.

There is a link in post 12 to stats on house fires - it was commissioned by a company selling fire detection devices but perhaps it is valid

A lot of the dishwasher fires were a fault in number of Siemens models, from about 20 years ago. These have long been recalled replaced due to old age.

I can't find statistics on this but I find it worrying that lap-tops continue to be used in beds and on top of soft furnishings. Laptops have fans that draw in air to cool components when they are in use. In scenarios where there is dust, lint, dried skin, fluff, hair, etc in the surrounding environment, these will be drawn in and can block the cooling pathways or even the fan itself.

My first suggestion is not to use laptops in this way and the second, as a regular maintenance step with the laptop powered off, is to vacuum clean the fan intake port (usually a grille on the side or bottom of the chassis).

Check leads and transformers (the block in the middle of the mains lead) for cracks or damage and change any that don't look up to snuff. Also, my pet hate in these devices is the 13 amp fuse in the mains plug. Ditch and replace it with a 3 or 5 amp fuse.
Why change the fuse?

For those of you running appliances by night, why don't you look to install solar panels and run your appliances from "free" energy, during the daytime, instead?

For those of you running appliances by night, why don't you look to install solar panels and run your appliances from "free" energy, during the daytime, instead?

I don't run appliances at night but solar isn't free either when you look at the cost of installation and it's dependent on individual circumstances if one has that investment cost to hand and the timespan left to recoup the cost!

For those of you running appliances by night, why don't you look to install solar panels and run your appliances from "free" energy, during the daytime, instead?
A few reasons.

Firstly the night rate is available every night at a fixed time, so you can just set a timer for forget. For many winter months there isn’t much solar generation happening, but even in the summer there are days/hours where there isn’t enough.

Secondly you’re paid more to sell solar during the day than you pay to buy electricity on the night rate. So you make money by exporting as much as you can during the day and shifting everything you can to the night rate.

PS. We have solar panels and love them.

I had an assessor at the house on an unrelated issue. I happened to mention that I had intended to leave the dishwasher running when I left on an errand. He warned me that dishwashers, dryers and washing machines are the most dangerous and should not be left running unattended. Smart meter fitted this week. Will sign up to day night plan but will not be running these unattended.
Seriously ! I leave all machines on when I leave and have done for decades. Literally load the dishwasher and washing machine and away I go. Some people turn on things like the oven from their office, via their phones.

Why change the fuse?
Lower amp would blow quicker than a 13A fuse.

That’s a fair point. A modern washing machine uses about 0.5kWh per cycle, a dishwasher a little less than 1kWh. Depending on your tariff you might save €0.15 per kWh on the nightrate. So we’re saving €125/year by running the appliances at night. Not nothing, but not huge either.
Wow, that's a complete waste of time then. For the sake of €2 a week and all the stress of trying to remember to put on the machine at night and time it.

How much do I save by using my dishwasher 95% of the time on a 29 minute cycle. I never use the heavy hot wash on the washing machine, I do the fast cycle which is one hour. I'd never considered that it cost a lot less, but I was concerned as to why dishes could possible need 2 hours to wash and the same with fairly clean clothes. Also the intense washes aren't good for clothes or dishes.

How much do I save by using my dishwasher 95% of the time on a 29 minute cycle. I never use the heavy hot wash on the washing machine, I do the fast cycle which is one hour. I'd never considered that it cost a lot less, but I was concerned as to why dishes could possible need 2 hours to wash and the same with fairly clean clothes. Also the intense washes aren't good for clothes or dishes.
It really depends on the machine, but in general a 29 minute cycle is not intended to be efficient, it’s intended to be quick. This person monitored the various cycles their dishwasher could do, the quick cycle took exactly the same amount of energy as the main cycle, whereas the Eco cycle used about 30% less energy - https://www.bentasker.co.uk/posts/b...y-efficient-is-eco-mode-on-a-dish-washer.html

I imagine the same applies to dishes and clothes when it comes to damage being done (and energy efficiency), better to do long washes at low temperates than a short washes at higher temperatures. The longer wash cycle allows soaking to remove dirt rather than having to blast it with high heat or vigorous spinning.

How can it cost more to do a 2 hours wash in the dishwasher than a 29 minute one?

I use the hot heat one about once a week to clean the machine mainly. Kills everything and destroy all grime.