Camping energy planning starts with watt-hours, not with the largest
battery on sale. List each device, its power draw and daily running
time. Then allow for conversion losses, reserve capacity and weak solar
conditions. The included camping power calculator performs the
arithmetic, but the method is simple enough to verify manually.
Enter watts and daily hours for each device. Voer per apparaat watt en gebruiksuren per dag in.
| Device / apparaat | Watts | Hours / uur |
|---|
Planning estimate only. Check actual device draw, startup surge, battery limits and local seasonal solar data. Dit is een schatting; controleer werkelijk verbruik, startpiek, acculimieten en lokale seizoensdata.
Watts, watt-hours and
battery capacity
Watts measure power at one moment. Watt-hours measure energy used
over time. A 40-watt camping fridge averaging eight hours of compressor
operation uses about 320 watt-hours per day:
Energy (Wh) = power (W) × running time (hours)
Battery makers usually publish usable capacity in watt-hours. A 1,000
Wh power station does not deliver every stored watt-hour to an AC
appliance. The inverter, wiring, battery management system and standby
operation consume energy. Dividing the device total by an assumed
efficiency gives a safer estimate.
Example daily camping
energy budget
| Device | Power | Use per day | Energy |
|---|---|---|---|
| Compressor fridge | 40 W average | 8 h | 320 Wh |
| Four LED lights | 20 W total | 5 h | 100 Wh |
| Two phones | — | — | 30 Wh |
| Laptop | 60 W | 2 h | 120 Wh |
| Water pump | 50 W | 0.3 h | 15 Wh |
| Daily total | 585 Wh |
At 85% system efficiency, 585 Wh of device use requires roughly 688
Wh from the battery. Adding a 20% reserve raises the target to about 826
Wh for one day. For two days without charging, double the daily
requirement before adding the chosen reserve.
Real consumption should replace label estimates whenever possible. A
plug-in power meter can measure AC equipment. For a fridge, measure a
complete warm day because the compressor cycles and outdoor temperature
affects consumption.
How large should a
portable power station be?
Add daily watt-hours, divide by expected efficiency and multiply by
the number of days between reliable charging opportunities. Add reserve
last. Do not routinely drain a battery to zero; usable capacity and
recommended discharge limits vary by chemistry and manufacturer.
Capacity is only half the specification. The inverter must also
support the continuous wattage and short startup surge of connected AC
equipment. Compressors, pumps and some cooking appliances draw more at
startup. Check the manufacturer’s measured or stated starting
requirement rather than guessing.
Heating devices dominate small systems. A 1,000 W kettle used for six
minutes consumes about 100 Wh, while an electric heater running for
hours can empty a portable station rapidly. Gas or campground mains
power is often more practical for sustained heating, subject to fire,
ventilation and site rules.
How much solar power is
needed?
A planning formula is:
Solar watts = daily Wh ÷ (peak-sun hours × system
efficiency)
For 585 Wh per day, four peak-sun hours and 75% solar-system
efficiency, the mathematical minimum is 195 W. Weather, shade, panel
angle, heat and seasonal daylight can reduce output, so a nominal 200 W
panel offers little margin in that scenario. Extra panel capacity or
another charging source improves resilience.
“Peak-sun hours” are not the same as hours of daylight. They express
the day’s solar energy as equivalent hours at 1,000 watts per square
metre. Use local seasonal data and plan around the least favorable
realistic conditions for the trip.
12-volt, USB or AC?
Use direct USB-C or regulated 12-volt outputs when equipment supports
them. Converting battery DC to AC and then back to low-voltage DC wastes
energy. Confirm voltage, connector polarity and current limits before
connecting a device; a matching plug does not prove electrical
compatibility.
Keep batteries dry, ventilated and within their specified temperature
range. Do not charge a lithium battery below its permitted temperature
unless its battery management system explicitly supports it. Follow
campsite rules for generators, solar placement and cable routing.
A reliable planning process
Create a device inventory, measure high-use equipment, calculate
daily Wh, include conversion losses, size for the longest expected
charging gap and add reserve. Test the complete system at home before
departure. A realistic 700 Wh load test tells you more than a capacity
claim alone and exposes unsuitable cables, inverter limits or
unexpectedly high standby use.
