Is a Solar Generator a Portable Power Station?

Traditional Panel Design

• The primary component of a solar generating station is the panel array, which is the system of panels that collect sunlight and turn it to electricity. The individual solar cells that form a panel produce energy by the photovoltaic effect, whereby incident sunlight creates a voltage across the semi-conducting material in each cell. The voltage across each cell is usually around half of a volt, and it takes a number of them, wired together in series, to make a panel. Panels assembled in the traditional way, with the cells attached to a solid substrate and covered with glass, quickly become too large to carry around. A typical 100-watt panel, for example, is about 2 feet by 4 feet.

Other Components

• When you form a line of solar cells by connecting them in series -- with the positive pole of one connected to the negative pole of its neighbor -- and you close the circuit in sunlight, a direct current begins to flow. You can use that current to charge a battery with the same voltage as the panel outlet. Because the output of the panel is variable, you usually need a charge controller to stabilize it. Moreover, if you want to use the output directly to run an appliance, you need an inverter, which is a device that converts direct current to alternating current and transforms the voltage to that of the appliance.

Suitcase-Style Generators

• Suitcase-style portable generators contain all the components necessary to convert sunlight to usable power and qualify as portable power stations. Unfortunately, there isn't enough room in a suitcase for more than a small panel and a lightweight charge controller. Consequently, the primary use for most suitcase-style generators it to charge batteries for laptops and cell phones, although some come with battery packs that can power small appliances. The output of the panels in such generators is often in the range of 7 to 15 watts, which is enough to charge four AA batteries in two to four hours of full sun.

Larger Portable Generators

• More useful solar generators may be too large to carry in a suitcase, but they will fit in the back of a pick-up truck and can still be considered portable. Such systems may consist of several panels that together can generate several hundred watts of electricity. They often include one or more rechargeable 12-volt batteries and an inverter to convert the battery power to 120-volt AC power suitable for household appliances. If the panels are packed efficiently, the generator can fit with all the other gear necessary for camping, and it doesn't take long to deploy them in a sunny location at a cabin or campsite.