Motorhome, caravan and RV
Energy setup for motorhomes and caravans
A modern motorhome is a home on wheels. The right energy setup runs a compressor fridge, induction hob, heating system, air conditioning, working station and entertainment — silently, from solar, without hookup. Here is everything you need to plan it correctly.
Why motorhome energy planning is different
- You live in it. Unlike a weekend campervan, a motorhome or full-time caravan setup must cover cooking, heating, cooling, work and entertainment simultaneously — often for days without grid access.
- The load profile runs 24 hours. The fridge never stops. Heating may run all night. Water pump, lighting and phone charging happen continuously. Daily Wh consumption is the key number, not peak watts.
- Three charging sources must work together: solar (primary), alternator/DC-DC (driving), and shore power (when available). A correctly integrated system prioritises solar, uses driving to top up and only relies on hookup as a fallback.
- Weight and space are real constraints. A portable power station replaces or supplements a traditional leisure battery bank — with more usable capacity per kg (LFP chemistry), integrated BMS protection, solar MPPT and a built-in inverter in one unit.
- Seasons change everything. Southern Europe in July: 6–7 peak sun hours, air conditioning load, 35°C ambient temperature pushing the fridge hard. Northern Europe in January: 1–2 peak sun hours, heating load, short days. The same hardware performs very differently across seasons.
Load profiles: light traveller to full-time resident
| Profile | Key loads | Typical daily Wh | Recommended setup |
|---|
| Weekend light |
12V fridge, LED lights, phone charging, radio |
600–1,000Wh |
C1000 or 2 kWh station + 100W panel |
| Active traveller |
12V fridge, LED lights, laptop, phones, water pump, occasional TV |
1,200–1,800Wh |
2 kWh station + 200W panel |
| Work + travel |
12V fridge, laptop, monitor, router/Starlink, lights, phones |
1,800–2,800Wh |
F2000 / 3-5 kWh station + 400W solar |
| Comfort motorhome |
Compressor fridge, induction (occasional), TV, laptop, heating fan, lights, water pump |
2,500–4,000Wh |
3-5 kWh station + 400–600W solar |
| Full-time residence |
All comfort loads + induction cooking daily + air conditioning (partial) |
4,000–8,000Wh |
F3800 × 2 or expanded system + 800W+ solar |
| Off-grid long-term |
Full house load + induction + AC + washing machine (portable) |
6,000–12,000Wh |
Custom system — assisted proposal required |
The fridge: your biggest continuous load
- A 12V compressor fridge is the correct choice for motorhome use. It runs directly from DC, eliminates inverter losses and uses Secop or Danfoss variable-speed compressors that consume 15–40Wh/day on average.
- Popular motorhome fridge options and real consumption:
| Model | Volume | Avg daily Wh (20°C) | Avg daily Wh (30°C) | Notes |
|---|
| Dometic CFX3 35 | 35L | ~240Wh | ~380Wh | Single zone, very efficient |
| Dometic CFX3 75DZ | 75L dual zone | ~380Wh | ~580Wh | Fridge + freezer independent control |
| Dometic CFX3 100 | 100L | ~480Wh | ~720Wh | Large capacity, still very efficient |
| Engel MT35 | 32L | ~260Wh | ~400Wh | Military-grade durability, excellent for rough roads |
| ARB Elements 63L | 63L | ~340Wh | ~520Wh | Dual zone, overlanding-focused build |
| Brass Monkey 130L | 130L | ~560Wh | ~840Wh | Large family capacity, dual zone |
| Waeco/Dometic absorption (3-way) | 60–100L | ~1,200–2,000Wh on 12V | Not recommended | Very inefficient on 12V; only use on gas or 230V hookup |
| Household fridge via inverter | 200–350L | ~1,800–3,600Wh | ~2,400–4,800Wh | Possible but demands large solar array; confirm inverter surge rating |
Absorption (3-way) fridges are extremely inefficient on 12V. If you have one, run it on gas when stationary and 230V on hookup. Never plan a solar system around 12V absorption consumption.
Solar sizing for motorhomes
- The basic formula: daily Wh needed ÷ peak sun hours × 1.25 (losses) = panel watts required. A setup using 1,500Wh/day in an area with 5 peak sun hours needs 1,500 ÷ 5 × 1.25 = 375W of panels.
- Van and motorhome roof space: a typical motorhome roof fits 400–800W of panels (4–8 × 100W rigid panels or equivalent flexible). A large A-class motorhome can accommodate 1,000W+.
- Panel types for motorhomes:
| Panel type | Efficiency | Best use | Notes |
|---|
| Monocrystalline rigid | 20–23% | Fixed roof with good sun exposure | Best performance per m²; standard choice for most motorhomes |
| Flexible monocrystalline | 18–22% | Curved roofs, low-profile vans | Good performance; avoid mounting flush without air gap — heat reduces output |
| Portable folding (briefcase) | 20–22% | Supplement fixed panels; adjust angle | Can be positioned for optimal angle; useful in partial shade situations |
| Bifacial | 22–25% | High-output fixed installations | Gain reflected light from below; useful on white motorhome roofs |
- MPPT vs PWM charge controllers: modern portable stations include an integrated MPPT controller. MPPT extracts 20–30% more energy from panels than PWM, especially in low-light and partial-shade conditions. Always use MPPT for motorhome solar.
- Partial shade kills production: one shaded cell in a string reduces the entire string's output. If your roof has obstructions (skylights, AC unit, antenna), consider panels with optimisers or independent MPPT inputs.
- Seasonal planning: southern Europe (Portugal, Spain, Italy) in summer: 6–7h. Winter: 3–4h. Northern Europe (Germany, France) in summer: 5–6h. Winter: 1–2h. Size your system for your worst expected location and season.
Charging sources: how they work together
| Source | Typical input | When it helps | Notes |
|---|
| Solar panels | 100–1,500W depending on array | Stationary and driving in sun | Primary source for off-grid; silent, free, zero maintenance |
| Shore power (hookup) | 1,200–2,400W AC input | Campsites, marinas, service areas | Fastest charge; an F2000 goes 0–100% in under 2h at 2,400W input |
| Vehicle alternator (12V DC) | 100–200W typical | While driving | Slow but consistent; adds 500–1,000Wh on a 5h drive day |
| DC-DC charger (B2B) | 20–60A = 240–720W at 12V | While driving, faster than direct | Recommended for serious setups; protects starter battery and charges faster |
| Generator (occasional) | 1,000–3,000W | Extended bad weather, heavy use | Emergency top-up only; noisy and requires fuel logistics |
Cooking on battery: what is realistic
- Induction hob (single, 1,000–2,000W): realistic for a station with 2,400W+ continuous output (2 kWh station class and above). Boiling 1L of water takes 4–6 minutes at 1,500W = 100–150Wh. Cooking a full meal typically uses 200–400Wh. One 2 kWh station can cook 5–10 full meals before recharging.
- Induction hob (double, 2,800–3,500W): requires 3-5 kWh high-capacity station class (6,000W peak output). Using both rings simultaneously at high power is intensive but viable for short bursts.
- Microwave (700–1,000W): viable from 2 kWh station class. A 5-minute reheat uses ~80Wh. Fine as occasional use.
- Electric kettle (1,500–2,200W): F2000 or 3-5 kWh high-capacity station class. A full boil uses 100–150Wh. Boiling water once or twice a day is easily sustainable even with modest solar.
- Air fryer (1,000–1,700W): 2 kWh station class. A 20-minute cook cycle uses 300–600Wh. Practical with good solar production.
- What is not realistic without shore power: a full-size oven (2,000–3,500W continuous for 30–60 minutes = 1,000–3,500Wh per use), dishwasher (1,200–2,400W for 60–90 minutes), or washing machine (1,500–2,500W for 60 minutes). These require either hookup or a very large solar + storage system.
- Practical hybrid strategy: use induction for quick cooking, gas for slow or large cooking (pasta, stew). This keeps battery consumption reasonable while eliminating dependence on gas for daily tasks.
Heating and air conditioning
- Diesel/propane parking heaters (Webasto, Espar, Chinese units): these use a combustion burner and only draw 8–25W from the battery for the fan and controller. A full night of heating (8h) uses 64–200Wh — negligible for any sized station. This is the correct heating solution for off-grid motorhome use.
- Electric fan heaters: 1,000–2,000W continuous. Completely impractical off-grid. One hour uses 1,000–2,000Wh. Never plan around electric resistance heating without hookup or a generator.
- Roof air conditioning (Dometic, Truma, Airxcel): 300–1,200W continuous, 1,000–3,000W startup surge. Running AC for 4 hours uses 1,200–4,800Wh. Viable only with 3-5 kWh high-capacity station class + substantial solar (600W+) in good sun conditions. Realistic in southern Europe in summer; not viable off-grid in northern climates.
- Portable evaporative coolers: 60–200W. Much more efficient than compressor AC but only effective in low-humidity environments (southern Spain, Portugal interior, North Africa). A practical alternative for moderate heat.
- 12V fans and ventilation: 5–30W. Roof vent fans (Maxxair, Fan-Tastic) pull hot air out at 10–25W. Essential for comfort in summer and negligible on battery consumption.
Water, pump and other 12V systems
| System | Typical watts | Daily Wh estimate | Notes |
|---|
| 12V water pump | 30–80W | 30–100Wh | Intermittent use; very low impact on daily budget |
| Hot water boiler (electric) | 500–1,500W | 300–1,000Wh | Use gas or diesel pre-heat where possible; electric is hookup-only for regular use |
| Diesel water heater (Webasto/Eberspächer) | 10–25W (fan only) | 20–50Wh | Recommended; uses diesel fuel, minimal battery drain |
| Roof vent fan | 10–25W | 50–150Wh | Run continuously in summer for ventilation; low cost |
| Satellite dish (auto) | 40–120W | 80–240Wh | While scanning and tracking; negligible once locked |
| Stereo / entertainment | 20–100W | 40–200Wh | Low priority but easy to include |
| Portable washing machine | 200–500W | 200–500Wh per cycle | Realistic with F2000+ and decent solar; 1 cycle/day manageable |
Battery technology: LFP vs AGM vs lithium NMC
| Technology | Usable capacity | Cycle life | Weight | Motorhome verdict |
|---|
| AGM / GEL lead-acid | 50% of rated (never below 50%) | 300–500 cycles | Heavy (25–30kg per 100Ah) | Outdated for serious use; fine for occasional weekenders with hookup |
| LFP (lithium iron phosphate) | 80–90% of rated (safe to 10%) | 3,000–6,000 cycles | Light (10–14kg per 100Ah) | Correct choice for all regular motorhome use. Safe, long-lived, tolerates deep discharge |
| NMC lithium | 80–85% of rated | 500–1,500 cycles | Lightest (8–12kg per 100Ah) | Higher energy density but shorter lifespan and more temperature-sensitive than LFP |
- Modern LFP power stations use lithium iron phosphate chemistry. This means you can discharge to 10–20% regularly without affecting cycle life, charge in partial states without damage and leave it at any charge level for extended periods.
- Comparing to traditional leisure battery banks: a 200Ah AGM bank gives ~100Ah usable at 12V = 1,200Wh usable and weighs ~50kg. A 2 kWh station gives 2,048Wh usable, weighs 17kg and includes solar MPPT, a 2,400W inverter and full BMS — all in one unit.
Real-world scenario planning
| Scenario | Daily load | Solar needed | Station | Verdict |
|---|
| Weekend wild camping, southern Europe, summer | ~900Wh (fridge + lights + phones) | 200W | F2000 | Fully self-sustaining |
| Digital nomad: work + fridge + cooking occasionally | ~2,400Wh | 400W | F2000 / F3800 | Self-sustaining in summer; needs driving top-up in winter |
| Family motorhome, 4 people, southern Europe | ~3,500Wh (AC occasional) | 600W | F3800 | Manageable with discipline on AC use |
| Full-time living, northern Europe, winter | ~4,500Wh (heating, low sun) | 800W+ or generator | F3800 × 2 | Challenging; diesel heater essential; hookup recommended when available |
| Overlanding: rough terrain, variable sun | ~1,500Wh | 200–400W + DC-DC | F2000 | Vehicle charging supplements solar gaps effectively |
Technical notes before requesting
- Tell us your fridge type (12V compressor, absorption/3-way, or household via inverter) — this single factor changes the sizing more than anything else.
- Confirm whether induction cooking is planned and how many times per day. One meal per day on induction is very different from three.
- State your travel region and season. Southern Europe in summer and northern Europe in winter are completely different solar scenarios.
- If you have an existing leisure battery bank, tell us the capacity and chemistry — we can assess whether the station replaces it entirely or works alongside it.
- For AC units, provide the model and its rated wattage. Startup surge for roof AC can be 3× running watts — this determines inverter class before anything else.
- If you plan to work remotely from the motorhome, include Starlink or router in the equipment list and your working hours per day.
Build a real autonomy estimate
Add each device, set the quantity and daily hours. The calculator totals your energy need, compares the available power station classes and shows how solar input changes the picture.
