I’m in the process of speccing my upgrade to a newer diesel pusher, and the segment has shifted hard toward “all-electric” coaches in the last few years — residential refrigerators, induction cooktops, convection microwaves, even washer/dryers as standard equipment on higher trim levels. As a mechanical engineer, my first question wasn’t “do I want these appliances,” it was “what does it actually take to run them off-grid without becoming a generator-dependent camper.” Here’s the real math.
The short answer: A genuinely capable all-electric boondocking setup needs 800-1,200Ah of lithium battery capacity and 600-1,200 watts of rooftop solar, depending on climate and how aggressively you run the residential fridge and induction cooktop. Below that range, you’re running a generator daily. Above it, you’re approaching shore-power independence in good sun.
In This Article:
- Why “all-electric” coaches changed the power math entirely
- Real watt and amp-hour numbers for residential fridges, induction cooktops, convection microwaves, and washer/dryers
- How to size a lithium battery bank for genuine boondocking, not just weekend trips
- The solar array size needed to actually recover what you use
- Where the JC Refrigeration 12V conversion fits — and where it doesn’t — in an all-electric coach
- A complete worked example for a typical all-electric diesel pusher
Why “All-Electric” Changed Everything
For most of RV history, the off-grid power conversation was simple. A propane-absorption fridge ran on gas, the cooktop ran on propane, and your battery bank only had to handle lights, water pump, furnace fan, and maybe a vent fan. A modest 200-400Ah of AGM and 200 watts of solar covered most boondockers comfortably.
The all-electric coach throws that entire calculation out. When the fridge, cooktop, microwave, and sometimes the dryer all run exclusively on electricity with no propane backup, your battery bank isn’t a convenience system anymore — it’s your entire kitchen and half your house. Undersizing it doesn’t mean running the generator a little more. It means your food spoils.
The Real Numbers: What Each Appliance Actually Costs You
Residential refrigerator (16-18 cu ft): This is your baseline, always-on load. Real-world testing on a residential fridge running off an inverter showed 2.4 kWh in 24 hours with the fridge alone in moderate conditions — and that number climbs significantly in hot climates as the compressor works harder. Expect 3-6 kWh daily depending on ambient temperature for a residential fridge running through an inverter. In desert summer conditions with the rig parked in direct sun, plan for the higher end of that range.
Induction cooktop: A three-burner induction cooktop pulls roughly 3,700 watts at full draw across all burners — though realistically you’re rarely running all three simultaneously at max power. A single burner during actual cooking typically draws 1,200-1,800 watts for the 15-30 minutes you’re actually cooking. Budget 0.5-1 kWh per typical dinner prep session.
Convection microwave: A 900-watt microwave draws roughly 1,500 watts total once you account for the inverter overhead and convection element. Most usage is short-duration — reheating, quick cooking — so daily consumption is usually modest, 0.2-0.5 kWh, unless you’re using the convection function for actual baking.
Washer/dryer combo: This is the appliance that breaks budgets if you’re not careful. A residential-style washer/dryer combo can draw 1,200-1,800 watts during the dry cycle specifically, and a full wash-and-dry cycle can run 2-3 hours. That’s a genuine 3-5 kWh hit for a single load — more than your fridge uses in a full day. If you’re boondocking and not connected to shore power, plan to run laundry only on high-sun days or skip it in favor of a laundromat stop.
Air conditioning, if you’re running it: Still the elephant in the room regardless of how electric your kitchen is. A single rooftop AC unit draws 1,200-1,800 watts while running, and if it cycles for several hours during a hot afternoon you’re looking at 10-14 kWh just from cooling. This is genuinely the limiting factor for most all-electric boondocking in summer heat — your battery and solar math needs to account for whether AC is part of your plan or not.
Sizing the Lithium Bank: Don’t Undersize This
Here’s where I see people make the most expensive mistake. They size their battery bank for a “normal” day and don’t account for the cumulative load of a genuinely all-electric kitchen plus actual usage patterns.
Run the math for a realistic all-electric boondocking day without AC:
- Residential fridge: 4 kWh (accounting for moderate-to-warm conditions)
- Induction cooktop, two meals: 1.5 kWh
- Convection microwave: 0.4 kWh
- Lighting, water pump, fans, electronics, Starlink: 1.5 kWh
- Misc and inverter losses (15-20% buffer): 1.2 kWh
Total: roughly 8.6 kWh per day for a couple running a full electric kitchen without AC or laundry.
At 12.8V nominal lithium voltage, that’s roughly 670 amp-hours of actual usable capacity needed per day if you wanted zero solar input — which nobody plans for, but it tells you your floor.
The practical sizing principle from people who’ve actually run residential fridges off-grid: a minimum of 800 amp-hours of lithium is recommended for serious all-electric boondocking, with 1,200 amp-hours of equivalent capacity giving you 3-6 days of buffer during cloudy weather without forcing a generator run.
My recommendation for a couple running a genuinely all-electric coach without daily laundry: 800-1,000Ah of lithium minimum. If laundry is a regular part of your routine or you’re running AC for any portion of the day, push that to 1,200-1,400Ah. This is not the place to split the difference to save money — an undersized bank on an all-electric coach means you’re running the generator every single day, which defeats the entire purpose of going all-electric in the first place.
Sizing Solar to Actually Recover What You Use
Your battery bank only solves half the problem. If you can’t recharge it daily, you’re just delaying the generator conversation, not eliminating it.
Using the 8.6 kWh daily draw from the example above, and accounting for realistic solar performance — not the nameplate rating, but what you actually get accounting for angle, partial shade, panel temperature derating, and charge controller efficiency — here’s the real math:
A well-positioned 600-watt solar array in good desert sun, accounting for roughly 5-5.5 effective peak sun hours and realistic system losses, will recover approximately 2.4-3 kWh per day. That’s well short of an 8.6 kWh daily draw.
To genuinely keep pace with an all-electric kitchen running daily, you need closer to a 960-watt solar array, which in good conditions can recover 4-5 kWh daily — still not full coverage of an 8.6 kWh day, but enough that your battery bank is doing manageable top-up work rather than draining toward zero every single day.
The honest reality: most all-electric diesel pushers boondocking seriously need 800-1,200 watts of solar paired with the 800-1,200Ah lithium bank to achieve multi-day independence without a generator. Less than that and you’re using your generous battery capacity as a buffer for a deficit you’re not actually closing, which means you’ll eventually run the generator regardless — the bigger bank just buys you more days before you have to.
Where 12V Conversion JC Refrigeration Fits — And Where It Doesn’t
This is a detail worth getting right because I see it get confused in RV forums constantly. The JC Refrigeration 12V DC conversion is not a way to convert a residential fridge to run on 12V. It’s a kit that replaces the cooling unit inside a traditional propane/electric absorption RV refrigerator — Norcold, Dometic — with a 12V DC compressor system, eliminating the unreliable absorption cooling unit entirely.
If your coach already has a residential refrigerator, JC Refrigeration’s conversion isn’t applicable — residential fridges already run on a standard compressor, just through an inverter rather than directly off 12V DC. The relevant power math for a residential fridge is the inverter overhead I covered above, not a DC conversion.
Where the JC Refrigeration conversion does matter for power planning: if you’re shopping older or used diesel pushers, many still run traditional absorption fridges rather than true residential units. If you inherit one of those rigs and the absorption cooling unit fails, as they commonly do, converting to the JC Refrigeration 12V DC compressor system is often a better long-term move than replacing with another absorption unit. It runs directly off your battery bank without inverter losses, it’s dramatically more reliable than absorption cooling, and it draws meaningfully less power than running a residential fridge through an inverter.
For a true all-electric coach with a factory residential fridge already installed, your power planning centers on inverter sizing and the battery math above, not a DC conversion.
The Complete Worked Example
Pulling this together for a realistic all-electric diesel pusher setup, here’s what I’d actually spec for my own upgrade:
Battery bank: 1,000Ah lithium (typically configured as four 250Ah or two 500Ah units depending on the manufacturer), giving roughly 12.8 kWh of usable capacity at a sensible 80-90% depth of discharge for lithium.
Solar array: 900-1,000 watts of rooftop solar, prioritizing the highest efficiency panels your roof space allows.
Inverter: A 3,000-3,500 watt pure sine inverter minimum to handle the induction cooktop’s peak draw without tripping, with surge capacity comfortably above 3,700 watts for the moment all burners fire simultaneously.
Realistic expectation: Two to three days of genuine independence running the full electric kitchen without AC, indefinitely sustainable with moderate sun assuming you’re not running laundry daily. Add AC into the mix and you’re looking at a generator assist on the hottest days regardless of how well you’ve sized the system — that’s just the physics of running 1,500 watts of cooling load for hours at a stretch.
This is the system I’m planning to spec on the next rig. It’s not cheap — a build like this runs $15,000-$25,000 in battery and solar hardware depending on brand choices — but it’s the difference between an all-electric coach that’s genuinely boondock-capable and one that’s a beautiful kitchen you can only use plugged into shore power.
Markus Bryant is a full-time RVer and remote mechanical engineer currently traveling toward Vancouver Island in his Holiday Rambler Nautica diesel pusher with his girlfriend and their dog Scout. He covers RV tech and mechanicals at RV Journal.
