washing machine off solar?

[bahamasolarnoob]

https://www.lehmans.com/p-2398-lehmans-own-hand-washer.aspx

2398_3_.jpg

Other hand washers get clothes clean; this one gets them really clean. We took an old favorite and improved on its design to offer you a new alternative.

Nice work out at the same time, you can wash on a cloudy day..

[moguitar]

We usually do our laundry on sunny days, too. The main thing is that most regular washing machines require sine wave power, and use more water and power. With off grid systems that are modified sine wave, and run off a well pump, then a Staber washer or something like it is needed. Low power use, 135 watt hours per load, and low water use, 15 gallons per load (big loads, too), and it will run off a modified sine wave inverter.
Of course, they are US made and may not be available in some countries.

[Vern Faulkner]

The wife and I, who are testing a system now while still on the grid, did four loads of laundry over the weekend, all run off inverter. We just waited for a pair of sunny days, and did laundry just at noon, or a bit before. Panels put out 200-300 watts/hour, machine pulled back a low of 50 watts to a high of 370 watts. All the load did, really, was delay the onset of a full charge.

We ran the machine with a Kill-O-Watt, while still on-grid, and determined it used, IIRC, 0.179 kw/hr of energy per load. Certainly not a mass amount of power for a reasonable system.

[cortijo]

I live 100% off grid.
I have a normal washing machine.

My advice would be to forget the idea of trying to buy enough batteries to run the washing machine or to store up enough energy to do a wash at night.
To even attempt that would be nonsense.

Wait for a sunny day when the sun input is around the same power draw as the washing machine.

Just buy about 800 watts worth of panels.
Get a fairly small battery just a 200ah monoblock lorry battery just to stabilize the system.
Get a 1000 watt inverter.
The most important thing is that the inverter can cope with the spin cycle.
I actually use a 750 watt inverter for my washing machine. It makes some odd noises but it is OK

The wash cycle uses 20 second bursts of about 400 watts.
The spin cycle can use around 800 watts for about 3 minutes.

A very important thing which nobody has mentioned is the temperature of the water.
Modern detergents are designed to be used at lower temperatures such as 40C so you can just use cold.
It would not be a good idea to use solar electric power to heat up the water because the heating element would be at least 1200 watts.
Instead you can buy a washing machine that has both a hot and cold input.
The hot input can come from solar heated water on the roof.
You would need a temperature combiner to make sure the water is not too hot otherwise you will shrink your clothes or discolor them.

In my own system I run the washing machine between 11am and 3pm on a sunny day.
The batteries hardly seem to show the strain because I have about 900 watts coming in from the panels.

A lot of times on this forum something is deemed unfeasable because of the need to do things under battery power.

Just make hay while the sun shines!

I also have sunny weather gadgets such as a 1000 watt electric kettle.
If the sun is shining I will boil water in the kettle if not then I will use gas.

[moguitar]

When I completed my attached garage addition in 1999, I had it running on 4 golf cart batteries and a UPG 1300/6000 inverter. I had 168 watts of panels and a BZ30 controller. I went out and bought an efficient Whirlpool front load washer and it would not run. Took it back and got my money, then bought a Staber2000 with a small dent for about $1K shipped (now $1.3K plus shpg.). I ran it off a 700 watt temporary inverter once (it is rated for as low as an 800 watt modified square wave inverter).
Two drops of oil yearly and some shoe goo to repair a few cracks in the plastic, and it has performed well ever since. It only used 1 oz of liquid wash for a standard large load(1/2 oz of Ultra), and now we are successfully using the Green Ball. It only uses 15 gallons of water per load and 135 watt/hours of power. The water comes from my front system, half of which is for our deep well (pure good tasting mountain water).
It sure beat the 2 gallon hand crank washer we used for the first couple years or going to the laundromat 19 miles away with lots of quarters. We use outdoor lines for drying and a 5 line extender wall to wall line in the garage in winter, with a supplemental Boxwood stove to dry them and provide supplemental heat to our Cozy Propane heater.

[billvon]

Yet I wanted something small enough and self contained so I would not have to re-wire the main panel which any interior lighting project would probably require in my older home.

How about a laptop? And is there a reason you don't want to go grid tied?

I showed that by my calculations I might be able to sneak by with only one deep cycle battery.

Well, sure you could. But it would be a big battery. You need about 40 amp-hours out of a 12V battery, which means you really need a 100 amp hour battery (don't ever want to go below 50%.) And that means one washing load a day; we rarely do less than 2 at a time.

The smallest I'd go would be two T-105's (golf cart batteries, 6V 220ah each) which you could probably get for $300.

I am NOT saying my calculations are correct and you are wrong. I came here to be educated. I am asking that you please explain why I need 4 deep cycle batteries with 140 minutes of reserve power @ 25 amp discharge rate, each, only to run a washer for 30 minutes. Seems overkill.

I'd suggest you get away from all this "reserve power" talk. "Reserve power" generally refers to car or marine starting batteries, and such batteries fail very, very quickly in RE applications. Just use amp-hours - and if the battery doesn't have an amp-hour rating, you don't want it anyway.

Cycled a few times a year, they only last 3-4 years?

With good UPS batteries you could get them to last 10 years with only 3-4 uses per year. Do you really use your washing machine only 3-4 times a year?

[yzahmad]

The way my solar is setup, I have a manual switch that allows me to turn on the inverter and take all connected lights/fans/appliances off the grid; my dad usually turns this switch on at 5-6am (sunrise), and I turn it off at sunset (so batteries do not charge from the grid and stay charged for the blackouts).

I noticed that by 11am, all my batteries were fully charged and the charge controllers stop feeding the batteries (current drops to 0.01a). So I've got a switchover installed that is connected to a deep freezer and fridge; I turn this over, and these two shift from the grid to the inverter. Before sunset, I turn this switchover back so the freezer and fridge go back on the grid, and if I see the batteries they are still charged 95% or more. Of course, if I was to forget to switch back one night my batteries may not survive, but I think its one way I can use 'excess' capacity from my panels without burdening the batteries.

[Dave_Rasch]

Hand Washer

I think that manual stuff is a good supplement to off-grid living. There's a plunger-like device called the Rapid Washer that works really well. It's an old technology that keeps on working.

[confused]

I was looking around the house thinking of an area where I could get my feet wet with solar. Some appliance that uses a decent amount of electricity so there would be some economic benefit, not just a proof of concept.

The best I could come up with was the washing machine. It's 110V @ 8amps. The longest wash cycle on it is about 30 minutes. So I believe that means it requires 440 watt hours.

This would obviously require a battery for storage. I looked at Optima Yellow, rating says 140 minutes of reserve capacity @ 25 amp discharge to 10.5 volts. I believe this is about 300 watt hours for 140 minutes.

Here's where I get lost. Can I compare those watt hour calculations? Can I assume that if the battery can supply 300 WH for 140 minutes, it will be able to do 440 WH for about an hour?

Then I realize I will lose power at the inverter, so that 1 hour will look more like 40 minutes, which should be enough for one wash cycle.

Are my calculations and concepts correct? I'm new to this, please go easy. Then all I need to figure out is how big of a solar array I'd need to be able to charge that battery in 48 hours or less. At my house I could face the array west or SW. Cleveland OH is the location.

Brian

Hi Brian
I notice that you have already received a veritable mountain of technical advice concerning your wish to run a washing machine from a solar source, so I won't presume to add to that.
However, I do live off-grid and I do run a washing machine. My advice, for what it is worth is, don't go there.
Assuming that you have enough cash to throw at the panels, the batteries, controller etc you will certainly need a pure sine wave inverter, as I found to my cost. My original setup was with a modified sine wave inverter and it took me an age and a lot of trips back and forward to find a washing machine that was SO simple that it would actually work at all. I have been forced to keep getting it fixed, as I am unable to find a replacement that will function. The more complicated washing machines these days just will not work, unless whirring a bit and then dumping water all over the kitchen floor is what you were after. i.e. getting your feet wet!
I'd pick a project that wasn't: a) so power hungry b) wasn't fraught with problems.
How about running your computer using solar power? Could be useful if there is an outage.

Regards
Confused

ps I have now upgraded to a pure sine wave inverter, so no more excuses to the missus the next time the washer breaks down.

[Sunking]

Optima Yellow would be better than a traditional deep cycle -- sounds like a DieHard Marine would do a better job and cost less.

Brian Optima is a great battery, but not especially well suited for a true Deep Cycle battery. If you are talking about say a mobile RE application like an RV or someone living out of a van or truck, Optima would be an excellent candidate. Optima claim to fame is their very low internal resistance which is just what you want for a very efficient charging and very high charge and discharge rates of C/2. To achieve that feat they had to make sacrifices and came up with the Jelly Roll AGM VRLA cell. To roll the plates requires them to be very thin, and use a lot of them. Consequently thin plates make for short cycle life.

Lastly Optima is really geared for the mobile market. For example tow truck companies, mobile mechanics, utility companies, high-end A/V enthusiast, and low rider electro-hydralic lifts require very large amounts of current and these application will use a Auxiliary battery and a very heavy alternator. Optima is what they use.

[Naptown]

Any battery that states CCA or x minutes of reserve is going to be a hybrid battery.
True deep cycle would be a golf cart battery on the low end and a true RE battery at the top end.
Since most people destroy their first set of batteries learning how to use and care for them the cheap battery is probably best. Save the big bucks for the second set.

[bxd20]

Rich-

Thanks for that reply. It answered a LOT of my questions. I had been going under the assumption that an Optima Yellow would be better than a traditional deep cycle -- sounds like a DieHard Marine would do a better job and cost less.

Most of all, thanks for the calculations as I can now take those and apply to other potential projects.

I agree that 4 batteries will take a lot more panel to charge than I had been hoping for. Will have to re-think.

Brian

[Naptown]

As I mentioned above Peukerts law comes into play
With a 12V battery the discharge rate would be about 80Amps
The battery you mentioned is a 66AH battery when discharged at the 20 hour rate or at 3.3 amps per hour.
That high a load reduces the amp hour capacity to 25.6 AH x12V = or 300 WH.
At this point the battery is dead you have drained it 100% and the spin cycle hasn't occurred yet.
If you drain a battery this far the number of cycles (discharge and recharge = 1 cycle) is dramatically reduced.
I could not find a chart for that battery for discharge depth vs # of cycles but I would imagine it would be less than 100
For longest life of a battery you want to discharge it on a regular basis no more than 20%, 50% occasionally not on a regular basis.
So if you need 400 Watt hours multiply this by 5 and divide by battery voltage.
In your case 400x5/12= 166AH battery
Or 400x5/48= 41 AH
Now we have to figure in peukerts law into the equation because of the high amp demand.
that 66AH battery in series at that rate is an 41AH battery each cycle is just about 20% depth of discharge.
If you used 4 of those batteries in series it works out about right.

Keep in mind that these are hybrid batteries not true deep cycle. You will not get nearly as many cycles from them as you would a true deep cycle.

[bxd20]

Sunking et al-

Thanks for your suggestions. I wanted a project that was large enough to really showcase solar power - running our rear exterior entry light (motion activated) just isn't that exciting, and since it's on about 3 minutes a day @ 19W, it's a completely negligible savings. Yet I wanted something small enough and self contained so I would not have to re-wire the main panel which any interior lighting project would probably require in my older home.

How are you arriving at $400 for batteries? I showed that by my calculations I might be able to sneak by with only one deep cycle battery. Perhaps I was being optimistic despite my inverter loss calculation - perhaps I would need 2 batteries which would be $200, not $400.

I am NOT saying my calculations are correct and you are wrong. I came here to be educated. I am asking that you please explain why I need 4 deep cycle batteries with 140 minutes of reserve power @ 25 amp discharge rate, each, only to run a washer for 30 minutes. Seems overkill.

Also I'm not sure why the batteries need replacement "every few years". I admit to not having experience with deep cycle batteries. Cycled a few times a year, they only last 3-4 years? I am used to my car batteries lasting 7, 8, 9 years even (vehicles garaged). I realize those are not deep cycle batteries. Again, I'm trying to learn about the lifespan of deep cycles.

Not a youngster at 36 but I am a newb to solar.

Thank you everyone.

[Patafil]

I have a super capacity GE washing machine. It was the cheapest one at the local Sears. Tested with a Kill A Watt for fun. During wash cycle, the device registered 405 watts and around 365 watts during the spin cycle, but it peaks at 1600 watts for a second or two when the spin cycle starts.