At Powerenz, Inc., we understand that every ounce of weight counts when one is backpacking over long distances, at high altitudes, or for prolonged periods of time. We asked several backpackers questions about the electronic devices that they carry. Unless one is car camping or hiking very short distances, serious backpackers generally feel that laptop computers are too heavy, and they do not bring them along. The electronic devices that they do carry include cell phones, small music players with headsets, like iPods, small battery chargers, communications radios or walkie-talkies, LED lights, flashlights, GPS's, and other small items. Several of the devices that they carry can be USB charged, and the others can be charged or powered via a source of 12-volt DC power by using a 12-volt DC adapter. Devices that require 120-volts AC (grid power) are generally avoided because the portable power system must include an inverter, and that requires more components, weight and volume. Unless the backpacker uses multiple devices for many hours each day, their power and energy needs are small.
The smallest and lightest source of power for a USB-charged electronic device is a solar panel that is designed for charging USB-charged devices (power output voltage = 5VDC). As long as good sunshine is able to strike the solar panel, it will produce electricity and recharge a USB-charged device, like a cell phone. If one is backpacking in a location where sunshine is expected to be good and to strike the solar panel, a solar panel and a cable that connects the solar panel to the USB-charged device may suffice. In the photo below, one can see our smallest and lightest weight 6-watt, USB-voltage solar panel in solid olive drab that can be used to charge and/or power up most USB devices in the presence of good sunshine.
In the photo below, one can see the next largest USB-voltage 12-watt solar panel in solid black that can be used to charge and/or power up all USB devices, including iPads, in the presence of good sunshine.
If sunshine cannot strike the solar panel, when a cloud passes over the sun, if the solar panel does not face the sun, if the sun goes down, or if the weather becomes poor, the solar panel will stop producing electricity. During those times, it may be helpful to have an intermediary battery in the system that can store the energy that is produced by the solar panel, and make the stored energy available for use at other times. Couple a solar panel with a small battery, both of which are configured for USB-charged devices, and you have a system that can provide power during times when the sunshine is or is not optimal, though at a cost of slightly more weight and volume. In the first of three photos below, one can see the 6-watt solar panel connected to, and charging a small battery pack that will store the harvested solar energy. In the second photo, one can see the charged battery pack is being used to recharge a cellphone. In the third photo, one can see a more powerful USB-voltage system that includes a 12-watt solar panel plus a larger battery pack that stores more solar energy. One can see the pair of USB ports in the battery pack into which one can plug a variety of USB-charged devices. For more details about portable solar power for USB-charged devices, please see http://www.powerenz.com/store/index.php?_a=viewCat&catId=40.
For electronic devices that require 12 volt DC power, a solar panel that is designed to recharge 12-volt batteries alone will generally not suffice because the voltage produced by such a solar panel is highly variable, and additional components will be necessary. In simple terms, the smallest and lightest source of power that will be useful for devices that require 12 volts DC power consists of a solar panel and a battery that can be recharged using the solar panel. The battery can be used to store solar energy and to supply power during times of bad weather, when the sun is not shining, at night, when it rains, or when sunshine is not able to strike the solar panel. The solar panel charges the battery, the battery stores the solar energy, and the energy that is stored in the battery can be used any time one chooses. A system that can provide 12 volts DC can also provide power to recharge a USB-charged device by using a 12-volt DC adapter. Many USB-charged devices already come with 12-volt DC adapters, also called automobile DC adapters or cigarette lighter adapters. If your USB-charged device does not come with a 12-volt DC adapter, we can provide one for you.
A system that supplies 12 volt DC generally comes with a built-in female cigarette lighter socket that is exactly like the cigarette lighter socket in an automobile. If your electronic device comes with an automobile DC adapter, and you would normally plug it into the cigarette lighter socket in your automobile, then it can be plugged into our system the same way. If your electronic device does not come with an automobile DC adapter, we recommend that you purchase one. If your electronic device must have 120 volts AC power, then an inverter will need to be added to the system. The inverter plugs into the female cigarette lighter socket, and converts the battery 12-volt DC to 120-volt AC. Your electronic device plugs into the AC outlet in the inverter for power. This process works fine, except that it adds weight and volume to the system, and is not as efficient as using 12-volt DC directly. When the inverter converts the battery 12-volt DC to 120-volt AC, 10-15% of the energy is wasted in the creation of heat. If one feels the inverter, it becomes warm. That is where some of the energy from the battery has gone. So, it is most energy-efficient to use a 12-volt DC adapter rather than an inverter to provide power for your 12-volt devices. In the three photos below, one can see an example of a very small and lightweight system that can provide 12-volt DC or USB power for small portable electronic devices.
For those who require even more power for larger electronic devices, like laptops, the photo below shows such a system. Even this small system may become a burden when hiking long distances.
From that starting point, as one's power and energy requirements increase, the weight and size of the portable solar power system must also increase. Powerenz, Inc. offers lightweight and easily portable solar power options for backpacking enthusiasts. Our backpacking systems can be enclosed in their own bags or packs, or can be configured to fit inside larger personal backpacks To discuss how we can customize a portable solar power unit to meet your unique needs, please call us at 770.639.2244.