Standalone circuit to power washing machine, is this possible?

[BarrySmith]

I live in the south east of the UK. The new energy tariffs are going to slaughter me so I am looking at ways of both saving electricity and possibly generating some as well. I have my washing machine and dryer in an outbuilding so was wondering about powering these two devices using only solar energy. Obviously these are two of the biggest energy hogs in anyones house so I’m going to need a fairly beefy system in order to do this. Has anyone on here any experience of creating a separate circuit in a house that is otherwise fed by the grid? Does this sound like a feasible project? Any advice would be gratefully received.
I know roughly what kit I would need, listed below:

Solar panels (at least 2 x 330 watt)

Charge controller

Power inverter

Batteries




Washing machine specs:
Connection rating 2300W
Current (A) 13

 

[John Frum]

Is it a combined washer/dryer or discrete units?
An electric dryer uses a lot of power.
Is a clothes line an option?

 

[BarrySmith]

The units are separate.
The dryer is mainly for the winter (which I realise makes things even harder for a project like this), we use the clothes line as much as we can already - just put a load out this morning!

 

[John Frum]

The units are separate.
The dryer is mainly for the winter (which I realise makes things even harder for a project like this), we use the clothes line as much as we can already - just put a load out this morning!

Is it electric?
If yes, that is likely going to be the load that dictates the max continuous rating for your inverter.
Will this system have the option to charge from the grid?
If yes, then you should look at an inverter/charger.

 

[SparkyJJO]

Washer and dryer in an outbuilding?
Man, and I thought it annoying to have my washer and dryer in the basement of our old apartment and having to lug laundry up and down 2 flights of stairs! I can't imagine trudging through rain, snow, and mud just to get a load of laundry done... and hoping it is still clean and dry by the end!

 

[BarrySmith]

Is it electric?
If yes, that is likely going to be the load that dictates the max continuous rating for your inverter.
Will this system have the option to charge from the grid?
If yes, then you should look at an inverter/charger.

Both devices are electric and I have power to the building so could charge batteries from the grid if needed. I was wondering about an automatic power switching circuit so as a failsafe against draining the batteries totally.

 

[BarrySmith]

Washer and dryer in an outbuilding?
Man, and I thought it annoying to have my washer and dryer in the basement of our old apartment and having to lug laundry up and down 2 flights of stairs! I can't imagine trudging through rain, snow, and mud just to get a load of laundry done... and hoping it is still clean and dry by the end!

It's only a few feet across an alley from my kitchen but this is what got me thinking about making a separate circuit, I suppose it's easier to think about it like that when the building is distinct.

 

[John Frum]

Both devices are electric and I have power to the building so could charge batteries from the grid if needed. I was wondering about an automatic power switching circuit so as a failsafe against draining the batteries totally.

An automatic transfer switch will do that and its a component of an inverter/charger.

 

[BarrySmith]

So, I'm a little confused about the numbers assigned to the various pieces of kit. If the washing machine is rated at 2300w does that mean I need to get at least a 3000w inverter?

Also, this totally blows my cover as an absolute noob, what happens if the batteries are fully charged but the sun is still shining and I'm not using the appliances? Does the controller protect the batteries?

 

[John Frum]

So, I'm a little confused about the numbers assigned to the various pieces of kit. If the washing machine is rated at 2300w does that mean I need to get at least a 3000w inverter?

The inverter will need to cover the LRA=locked rotor amps rating of the washing machine.
That number could be 3-5 times the 2300 watts the washer claims.
This may still be less than the draw of the dryer.

Also, this totally blows my cover as an absolute noob, what happens if the batteries are fully charged but the sun is still shining and I'm not using the appliances? Does the controller protect the batteries?

A decent quality, properly configured solar charge controller will not overcharge the batteries.

 

[John Frum]

@BarrySmith does the washer heat the water?

 

[BarrySmith]

@BarrySmith does the washer heat the water?

It does, it only has a cold water inlet.

 

[BarrySmith]

The inverter will need to cover the LRA=locked rotor amps rating of the washing machine.
That number could be 3-5 times the 2300 watts the washer claims.
This may still be less than the draw of the dryer.

A decent quality, properly configured solar charge controller will not overcharge the batteries.

The rotor amp thingy looks like it means I'm going to need an incredibly large amount of batteries or some kind of industrial inverter?

 

[John Frum]

It does, it only has a cold water inlet.

Can you just wash your clothes in cold water?

 

[BarrySmith]

Can you just wash your clothes in cold water?

The lowest setting I have is 30 degrees and is a 15 minute cycle. I actually use this and am quite happy with it but the missus reckons it doesn't get the clothes clean (by extension this means she thinks I'm a smelly git). I wonder if running the water supply through a solar water heater might make more sense?

 

[John Frum]

The rotor amp thingy looks like it means I'm going to need an incredibly large amount of batteries or some kind of industrial inverter?

2300 watts is a very load for a washer.
I think that may include heating the water.
Please include a product link so we can get a better idea of the washers peak draw.

Its probably a good idea to measure the actual load using something like this.

Kill A Watt Meter - Electricity Usage Monitor | P3

 

[John Frum]

The lowest setting I have is 30 degrees and is a 15 minute cycle. I actually use this and am quite happy with it but the missus reckons it doesn't get the clothes clean (by extension this means she thinks I'm a smelly git). I wonder if running the water supply through a solar water heater might make more sense?

Lots of people get good results washing their clothes in cold water.
I use cold water because the clothes last longer.

 

[John Frum]

Please also provide a product link for the dryer.

 

[BarrySmith]

This is the washer:

https://media3.bosch-home.com/Documents/specsheet/en-GB/WAE28368GB.pdf

As I understand it modern detergents will work in cold water and I actually tried to buy a cold water machine a few years back, had no luck though. Most mains water is going to need a fair bit or heating to get to 30 degrees isn't it?

 

[MichaelK]

Three comments, the two related to posts 12 &13. Sounds like you will be needing a larger inverter that what you were originally expecting. If the washer has a heating element, that is going to be a serious drain. Also, because the washer is motor-driven, it will draw "inrush current" higher that what the nameplate indicates. The what SJ is mentioning in post 10. If you are looking at loads in the 2300W level, I'd be looking at inverters in the ≥4000W range.

Getting back to post one, if the goal here is to save money, then this is NOT going to happen. Grid electricity is simply the cheapest way to power anything, and OFFGRID solar is the most expensive. If the goal here was independence rather than cost savings, then I'd say go for it. But, you will NOT save money.