Know how it works. With the exception of geothermal and nuclear power, the world's energy all originated in the sun. Solar power is a shortcut that allows you to capture and use our star's energy. When sunlight hits a doped semiconductor, such as silicon, the photons knock electrons free to produce electricity from their movement. By putting wires into the solar transducer to draw off the juice, you've created a photovoltaic cell. PV cells can be made into a single large sheet or combined into a large array of hundreds to make solar panels. The power created is direct current or DC, the same as you get from a battery. On a boat or recreational vehicle you'll be storing the power that you generate in your 12 volt on board batteries.
Determine the capacity. Estimate how many watts you plan to use. The power you need for a marine radio will be far less than you would use for a wide-screen TV with a DVD player. The less power you use, the smaller the system you'll need. Determine where you can cut power consumption, such as swapping your incandescent lights for fluorescent lights or light emitting diodes (LED) and going to LCD screens if you plan to watch TV.
Understand the parts you'll need. Most systems consist of solar panels, a charge controller, mounting structures, output wiring, cables, fuses, batteries and an inverter. Once electricity is generated by a solar panel, it is regulated by a charge controller which protects your batteries from being overcharged or undercharged. The controller ensures maximum battery life. Digital charge controllers include an LED display that monitors your entire power system. Mounting structures secure the panels to your deck or roof and should be waterproof. Inverters are to power your AC devices.
You'll need a slew of cables, including the inter-module cables that connect one solar panel to another, the output cables that connect the photovoltaic cells to your junction box, the cable that runs from your controller to battery and the cable that takes your power output to your inverter.
Choose deep cycle batteries. Car batteries are designed to generate high starting current for a short period to fire up an ignition. They are rarely fully discharged because a car's generator replenishes the power as soon as the engine runs. The interior plates on the batteries resemble lead sponges and offers a large surface area for quick, high current generation. These will fail after as few as 30 deep cycles, but will hold up for thousands of starts. Deep cycle batteries have a solid lead plate surface, so they generate less initial current but last longer. They can be consistently discharged by 80% without damage.
Match your power needs to an inverter, rated in watts, which is essential to turn the 12 VDC generated by your system into 110 AC power for your microwave, power tools and other devices.
