When preparing for an outdoor excursion one of the most important but often overlooked aspects is estimating your power consumption. Whether you are hiking, preparing meals, using a headlamp, or powering electronics, understanding how much energy you will consume helps you pack the right supplies.

Start by listing all the electronic devices you plan to bring. Common items include a headlamp, a GPS-enabled device, a GPS unit, a digital camera, an outdoor audio device, or a small stove with a battery-powered ignition. For each device, refer to its technical specifications. Most devices provide details in the user guide. If it's in watts, take the wattage and multiply by daily usage time to get watt hours. For example, a 5-watt device operated four hours daily totals 20Wh of energy.

For battery-powered devices listed in milliamp hours, convert to watt hours by multiplying the milliamp hours by the voltage and then dividing by 1000. Most phones and best portable power station banks run on a nominal 3.7V. So, a 10,000 mAh unit stores 37 watt-hours 10000 times 3.7 divided by 1000.

Then, assess your daily usage patterns. Be realistic. You might plan to use GPS minimally to conserve power, not continuously. Consider that cold weather can reduce battery life significantly, so add a 20 to 30 percent buffer to your total energy needs.

Calculate the total daily power demand to get your overall daily power need. Multiply that number by the number of days you will be camping to find your cumulative energy target. For example, your 50Wh daily use over five days equals 250Wh.

Select your energy solutions. Solar chargers work well in open sunlight but struggle under overcast skies or dense canopy. External battery packs offer consistent performance, but make sure their total capacity exceeds your calculated need. A 250 watt hour power bank would be ideal for the example above, but you might want to carry a 300Wh backup for margin of error.

For fuel-powered cooking, remember that fuel like white gas or propane also counts as energy. Most stoves consume 100–200g of fuel per cooking session. Schedule fuel for three main meals daily, and add a little extra for boiling water or emergencies.

Finally, always bring a backup. Bring redundant power sources, a traditional magnetic compass, a printed topographic map, and a flint striker. Electronics can malfunction, but manual equipment never runs out of power. Through careful forecasting of your electrical demands, you can venture confidently knowing your energy supply won’t fail.