QUESTION: How much solar power do I need for camping?

Answer supplied by National Luna.

Click here to view National Luna’s range of solar-ready products.

To answer this question you first need to know:

  • How much energy are you using on a daily basis?
  • How much time do you have to replace it?


Naturally, your 12V camping fridge plays a big role in your energy use over a 24-hour period. However, calculating that power consumption can be difficult when there are so many variables at play, including: The ambient operating temperature, the time of the day, how often you open and close your fridge, and of course, your preferred fridge / freezer temperature.

Typically speaking, a premium 12V camping fridge may use between 30Ah and 45Ah over a 24-hour period. Depending on daylight conditions, as well as your geographic location, most campsites have anywhere between 2- and 7-hours of usable solar energy.

Considering that an 85W panel produces roughly 5 amps per hour in ideal conditions, you would need at least 7-hours to replenish 35 amps.

Of course, the above calculation is radically simplified and based on minimum solar requirements as per: fridge size, performance, operating conditions, and how often you’re opening and closing the fridge. What’s more, the calculations don’t account for non-ideal conditions such as:

  • Dew / Dust on your solar panel
  • Partly cloudy weather
  • High ambient temperatures and additional strain on your fridge
  • How many appliances you’re powering, and…
  • The fact that you need to power your fridge at the same time that you’re recharging your auxiliary battery
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This is why it’s best to upsize the panel to a 120W / 150W unit if you’re thinking in terms of minimum requirements.

What’s more, upsizing your panel size will help to produce enough energy to power additional camping accessories such as LED lighting, and/or a cellphone charger. In some cases, many campers may even opt for a 200W or 250W panel for an additional margin.

However, bear in mind that your regulator would need to be rated to this capacity, and that such a panel may be impractically large in the case of non-flexible units.


Once you start calculating your energy consumption, it becomes clear that optimising your energy usage is far more practical than buying the biggest panel that will fit in/on your vehicle.

What’s more, some campers make use of a 220V inverter to power their camera and/or laptop chargers, without realising that the inverter itself is drawing significant energy. If possible, it’s generally best to substitute your 220V camera / laptop charger with 12V USB alternative. This alone can eliminate the need for an inverter and cut your energy use in half.

On that note, it would be wise to increase your solar power to a 200W panel if you’re forced to use an inverter, and, to make use of a MPPT solar regulator as opposed to a PWM unit.

Naturally, other energy cutbacks can be made in the form of efficient LED lighting, as well as opting for a fridge / freezer with high-quality insulation, compressor performance, and a correctly sized power cable. Other energy saving tips include…

  • Always keep your camping fridge / freezer’s latches closed to ensure optimum seal performance.
  • Never pack items around the fridge’s ventilation. Doing so will raise the operating temperature and use more battery power.
  • Set your camping fridge / freezer’s temperature to a low setting while driving, then adjust the temperature to a more economical setting once you arrive at camp.
  • Avoid parking your vehicle directly in sunlight.
  • Keep your camping fridge as full as possible.

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