Perhaps the title sounds a bit cock-eyed. "What does your solar panel do in winter, Joe?" "Mine? It just lies around and sleeps, Frank!" For some that may be true, but not everyone lays up the rig in winter. A fair number of folks head out to warmer climates when the first bite of frost pinches their proboscis. Or should that be probosci? A grammar whiz, I ain't.

In any event, if you'll be using your solar panels this winter, this piece is for you. If not, just dream about being warm, as you shiver under multiple layers of blankets and contemplate the ice cubes forming on your furnace.

As the days grow shorter, the effective hours of solar panel use are greatly diminished. Getting every last available watt out of your panels is the key. First, let's take a moment to discuss panel maintenance and efficiency.

Solar panels are greatly affected by the least bit of shadowing. Hence, when you locate panels on your roof--or on the ground should you choose that route--make sure they're shadowed as little as possible. Antennas, storage pods, air conditioning units, roof vents, etcetera, all can lay darkness across your producing surface. But a more insidious element can have an effect on output: It's an ugly word and it's DIRT.

When we pulled in off the road in the great southwest, we made a rooftop inspection. At first blush the panels didn't seem that bad, but a closer look revealed a hazing film of road dust and pollen, and assorted "dirty bird" calling cards.

Keep your panels clean! Your panel's manufacturer likely recommends a specific way of cleaning your photovoltaic investment. If you don't have the information, the safest way is to take a soft, wet cloth after it. Wipe the surface, turn the rag to keep from grinding the dirt on the panel face, rinse out. Now take a dry, soft cloth and get the last of the film off. Cleaning panels can dramatically increase their output.

From fall to spring, as the sun lies in the south (at least from our perspective here in the northern hemisphere), solar panels are not getting a fair shake from Sol. Panels are most efficient when the sun's rays strike them at a 90 degree angle. Tilting your panels can markedly increase output. We know that some say, "Just add another panel and leave 'em all flat." Priced solar panels lately? I don't mind getting out the ladder and taking a few minutes to set mine.

But how do you know at what angle to set the panel? It depends on your location. Here's a chart to help:

Cities in the US from west to east, followed by their approximate latitude.  The "tilt" listing is for degrees of tilt for the panel at that latitude.

Brownsville, TX/Key West, FL Approximate Latitude: 25 Tilt: 25

Corpus Christi, TX/ Tampa, FL Approximate Latitude: 28 Tilt: 31

Austin, TX/Saint Augustine, FL Approximate Latitude: 30 Tilt: 35

Tucson, AZ/Savannah, GA Approximate Latitude: 32 Tilt: 39

Los Angeles, CA/Willmington, SC Approximate Latitude: 34 Tilt: 43

Las Vegas, NV/Raleigh, NC Approximate Latitude: 36 Tilt: 47

San Francisco, CA/Richmond, VA Approximate Latitude: 38 Tilt: 51

Redding, CA/Philadelphia, PA Approximate Latitude: 40 Tilt: 55

Medford, OR/Providence, RI Approximate Latitude: 42 Tilt: 59

Eugene, OR/Portland, ME Approximate Latitude: 44 Tilt: 63

Portland, OR/Duluth, MN Approximate Latitude: 46 Tilt: 66

Everett, WA/Grand Forks, MN Approximate Latitude: 48 Tilt: 68

The chart lists major cities on opposite ends of the country and gives approximate latitudes for them. Find your location along a parallel between these cities, then use the information to determine the required angle for solar panel tilt.

For example, if you're staked out in Quartzsite, Arizona, you're approximately on the same parallel as Los Angeles and Willmington, about 34 degrees. Tilt your solar panels about 43 degrees, as measured from the flat surface of your roof. Of course, you'll need to orient your RV relative to the sun's path, appropriate to your solar panels.

Some RVers have come up with systems that allow them to turn their panels to "track" the sun's path. From the simple: A turntable affair with an attached rope. To the elaborate: An automated system that uses photocells to vector the position of the sun and a motor drive system to automatically follow Sol's daily stroll through the heavens. In any event, the more sun on the panels, the richer your battery bank account.

Heat also has an effect on panel output: The higher the temperature, the less the power produced. Tilted panels will have more "breathing space" and tend to stay cooler. If you need to "flat mount" use brackets that lift them up off the roof so air can freely circulate under them.

If you chose to "mount" your panels on the ground, mount them securely. Our first solar panel was ground mounted and all went well for a few weeks. One afternoon though, we returned home to find a sudden gust of wind had smacked our panel, face down, onto a bed of rocks. We learned how to repair a broken panel from that experience.

Kept clean and properly tilted, your solar panels will deliver the most bang for your solar investment. Even the short days of winter can be productive.