Can I run a washing machine on solar?

Looking at getting a washing machine into my garden office setup and wondering if it's actually viable on solar without a massive battery bank.

Current setup: 6kW nominal solar (mix of Fogstar and Renogy panels), Victron Multiplus inverter, and about 15kWh usable battery storage. I'm running lights, heating, occasional power tools, and an EV trickle charger most days.

Here's what I'm trying to work out — most domestic washers pull 2-3kW during the heating cycle, yeah? That's a serious spike. I've read some folk on here mention timing loads around solar peaks, but realistically in winter that's not going to cut it.

A few questions:

1. Is a heat pump washer actually more efficient, or am I just moving the problem elsewhere? I keep seeing them marketed as eco but haven't found solid figures on actual grid draw comparisons.

2. Would a smaller capacity machine help? I'm thinking about the compact 3-4kg models instead of a full 7kg unit. Less water heating = lower peak demand?

3. Has anyone had success with a timer/smart relay setup to prevent the machine running the heating cycle unless battery's at a certain threshold?

I'm not opposed to running off grid storage for this — it's not like I'm doing 10 loads a week — but I want to avoid the battery cycling becoming a bottleneck for everything else.

Thoughts? Anyone actually got a washer working reliably in a similar setup?

Mate, you're looking at a proper challenge there. Washing machines pull 2-3kW when heating water, and that's where solar alone falls flat — you'd need the sun hammering down right now, not stored power.

The battery bank to handle even a compact machine? We're talking 10-15kWh minimum to avoid voltage sag killing your inverter. That's serious money and space you probably don't have in a garden office.

What I've done in the motorhome is accept the reality: smaller loads when the sun's strong, or accept you need mains backup. Some folk go hybrid — solar tops up the tank during the day, then run the machine in late afternoon when batteries are full.

If you're married to the idea, a manual or caravan-spec machine uses a fraction of the power, though obviously not ideal. What's your actual battery capacity currently? That'll determine what's realistic for your setup.

Depends what you're after really. If you mean a proper washing machine, yeah you're gonna struggle unless you've got ideal sun and a chunky battery. The inrush is brutal.

That said, I've got a compact 12V unit on the boat and it's transformed things. Uses maybe 400W, takes ages but honestly? Worth it if you're off-grid. Won't heat water to 60°C though, so you're doing cold washes mostly.

If you're dead set on a standard machine, could work if you:

• Run it midday peak sun only
• Accept you need batteries to smooth the spikes
• Maybe go hybrid with mains backup

What's your battery setup like currently? That'll be the real limiter, not the solar. @BoxerCamper's right about the heating draw — that's where it all goes pear-shaped.

The real issue isn't peak power draw—it's sustained demand during the heating cycle. A standard washing machine will pull 2-3kW for 20-30 minutes, which means you need either:

Direct solar option: Run washes only during peak sun hours (10am-2pm) on clear days. You'd need decent irradiance and accept limited flexibility.

Battery route: A 10-15kWh bank would handle most wash cycles without draining completely, but that's considerable capex and requires solid charge controller sizing.

Worth considering: caravan/RV machines (1kW heating element) or manual/semi-automatic units. I've got a portable Intex in my shepherds hut setup and it genuinely works—minimal heating, flexible scheduling.

@DodgyRoamer, what's your actual daily load profile like? If you're only washing occasionally, timing it right might be more practical than oversizing the system.

The heating cycle's the killer, but here's what I've learned on the narrowboat: timing is everything. I run a compact Waeco unit during peak solar hours only—never in winter—and it's transformed things.

Your 6kW array is decent, but the real bottleneck is what battery capacity you're hiding. If you've got 10kWh usable, you could manage a cold-water wash in summer, no bother. Hot water? You'd need to either:

• Accept running it mid-day only when the sun's properly doing its job
• Split the cycle across two days (wash in sunlight, spin/rinse later)
• Size a battery bank specifically for this (gets expensive fast)

@LH_Marine's spot on about sustained demand. I'd honestly suggest starting with a smaller portable unit—Dometic or similar—and see if your actual solar production matches the marketing claims. Once you understand your real surplus, you'll know whether a proper machine is feasible or fantasy.

What's your battery bank looking like currently?

Have you looked at running it on a timer during peak solar hours? That's the angle I've not seen mentioned yet.

I've got a similar setup with the garden office and was dead set on a washing machine until I did the maths properly. The issue @LH_Marine flagged is spot on—it's not just the 2-3kW heating element, it's that it runs for 20+ minutes solid. Even with decent battery capacity, you're looking at draining reserves fast.

What's actually worked for me is a compact 3kg model (Candy or similar budget ones) timed to run mid-morning on decent weather days. Smaller drum = lower heating demand and shorter cycles. Not ideal if you need daily washing, but perfectly workable for a garden office setup.

How often would you actually be using it? That'll determine if a compact unit's realistic or if you'd be better off with the laundromat compromise.

The heating cycle is brutal, yeah, but @DodgyMechanic's got the right idea about timing. On my narrowboat I solved this differently though—switched to a 12V portable wash unit (basically a glorified bucket with agitation) for daily stuff, kept a proper machine for the deep cleans.

Thing is, if you're committed to a full-size machine, you're looking at either running it during peak solar and accepting battery drain, or adding a cheap immersion heater controller so the heating only kicks in when you've got genuine surplus. I've seen folk do this with a Victron MPPT's relay output—bit of jiggery-pokery but it works.

What's your battery capacity sitting at? That's where the real answer lives.

The heating element's absolutely the bottleneck here. I learned this the hard way retrofitting my van conversion — ran the numbers expecting it'd work with my 10kWh LiFePO₄ bank, but a single wash cycle was draining it faster than solar could replenish on cloudy days.

What @DodgyMechanic and @Spider are hinting at is spot on though. I've had success with a dual-approach: use a compact machine (Indesit or similar, around 1.5kW) and time it for midday solar peaks when you're genuinely producing. Crucially, switch off the heating function entirely and use cold water cycles — you lose nothing practically for garden office use, and suddenly the power draw drops to maybe 500W.

Battery-wise, 5-6kWh would be your minimum safety margin. Any less and you're constantly sweating it.

Worth considering a hybrid approach — solar for spin/agitation, mains for heating only if you've got grid access nearby?

The timing angle @DodgyMechanic mentioned is spot on. I've got a similar setup with mixed panels and the real killer is that heating cycle — easily 2-3kW sustained.

What actually works for me: ran a basic manual-fill washing machine (no heating) through a 5kWh battery bank. Runs the spin and wash cycles mid-afternoon when solar's pumping. Cold water only though.

If you want heated cycles, you're looking at either:

• Seriously oversizing your battery (not ideal)
• Running it grid-tied with export credits offsetting the draw
• Going cold-water and accepting the tradeoff

Honestly, for a garden office setup, cold water + good spin cycles keeps clothes damp rather than soaked. Drying's usually not the bottleneck if you've got outdoor space.

What's your battery capacity currently? That'll determine what's actually feasible.

The heating element's your enemy here — even a modest 2kW machine will tank your battery state of charge in minutes. You'd need either massive battery capacity or serious grid backup to make it work reliably.

That said, timing's everything. I run mine midday during peak solar, and it actually works if you've got decent irradiance. The trick is catching when your array's pumping out full watts — not ideal but doable in summer months.

Real talk though: if you're properly off-grid, a gas or LPG machine makes far more sense. Or invest in a quality hand-cranked option as backup. Your battery bank will thank you, and you won't be sat watching clouds wondering if the cycle will finish.

What's your battery capacity at the moment?

The heating element's definitely the villain, but here's what actually matters: when you run it, not whether you can.

I've got a 2kW machine in my static caravan setup with a Victron 48/5000 and 15kWh usable battery. Runs fine during peak solar hours (10am-2pm roughly) when I've got 4-5kW generation happening. The trick is using a decent inverter with passthrough capability so you're drawing solar directly when available, battery only for the pump and control circuits.

For a garden office, honestly, consider a smaller capacity machine or look at grey water recycling if you're washing work clothes frequently. A full 7kg wash cycle needs sustained draw that most hybrid setups struggle with unless you're timing it perfectly.

What's your inverter capacity? That's usually the actual limiter before the battery specs become relevant.

The heating element's a red herring if you're smart about timing. I run a basic Bosch in my shepherds hut setup during peak solar hours—typically 11am to 2pm—and it's entirely manageable on my 8kWh battery without draining anywhere near to dangerous levels.

Key thing is the cold wash cycle. Most of your laundry doesn't actually need hot water. Saves you roughly 80% of the energy draw compared to a heated wash. I'd genuinely look at a machine with a good cold-wash option rather than obsessing over battery capacity.

Your 6kW array is decent. The real question is: what's your actual battery bank looking like? If you're running off less than 10kWh usable, you'll want to be selective. But if you've got reasonable capacity and can stick to midday running, a standard 2kW machine is totally workable.

Also worth checking your inverter specs—some struggle with the inrush current when the heating element kicks in, even if the sustained draw would be fine.

The thing that's not been mentioned yet is your actual usage pattern. I've got a similar setup on my narrowboat and the washing machine works fine, but only because I'm disciplined about it.

Here's the real constraint: you need to match your machine's peak draw to your available inverter capacity, not just your solar generation. Most standard machines pull 2-3kW on the heating cycle. If your inverter can't handle that sustained, you're stuffed regardless of battery size.

What I do is run mine during peak solar hours (roughly 10am-2pm depending on season) and I've manually disabled the heater cycle—cold wash and a separate kettle boil works out cheaper anyway. The spin cycle is fine, it's just the heating that murders your state of charge.

If you're set on heated washes, you'd realistically need either:

• A 10+ kWh battery bank (significant investment)
• Mains backup (defeats the purpose)
• Accept you're only doing laundry when there's proper sun

What's your inverter spec and actual daily usage pattern? That'll determine if this is viable or

Right, what everyone's dancing around here is that you don't actually need massive battery capacity—you need smart load management. I've got a similar headache on my conversion van, and here's what actually works:

A standard washing machine pulls 2-3kW during the heating phase. That's genuinely manageable if you're running it during peak solar hours (10am-2pm roughly) and your battery's reasonably charged beforehand. The issue isn't the peak draw—modern inverters handle that fine—it's the duration combined with cloudy weather.

I'd honestly skip the dedicated battery expansion and instead get a decent timer or a Victron GX device to automate the whole thing. Program it to only run when you've got minimum 80% battery AND solar generation above 2kW. On my setup, a 5kWh battery handles a full wash cycle without drama because I'm not relying on stored energy alone.

Skip cold-water-only machines though. You'll genuinely regret that compromise for the sake of a slightly easier power budget.

What's your current battery capacity? That's actually the only number that matters here

The elephant in the room that nobody's mentioned: washing machines are inductive loads. Your inverter needs to handle the startup surge, which is typically 3-4x the running wattage. A 2kW machine pulling 9-12kW on spin cycle will trip most standard setups.

I've been running a compact Bosch on my narrowboat for two years now. Key learnings:

• Soft starter is your mate here—cuts that inrush current dramatically. Cost you about £80-120 fitted.
• Time your wash for midday sun. Dead serious. I only run mine 11am-2pm in summer, autumn I skip it entirely.
• Battery bank doesn't need to be massive if you're disciplined. I'm running 15kWh usable and it's fine because I'm not fighting physics—I'm working with the sun.

The real cost isn't the batteries, it's the inverter size and soft starter. You'll want at least 5-6kW pure sine wave, ideally 8kW.

What's your actual battery capacity at the moment? That