Solar Power

A solar power system is an amazingly straightforward setup, which makes you wonder why more people have not gravitated that direction. Part of it, of course, is that a complete "system" involves more than just the electricity-generating equipment. It also involves conserving energy in your house and in your daily life. The more energy-hungry devices you run, the larger solar power system you'll need to install.

We'll consider a photovoltaic, or PV system first. Of course, you'll need one, probably more, photovoltaic panels. These are comprised of numerous PV cells in a frame that can be mounted in a sunny location, like on the south-facing slope of your roof (assuming you're in the northern hemisphere).

Some sort of mount is generally required so your PV panels don't slide off the roof, and you'll also need a charge controller to regulate the charge going into your battery bank. An inverter converts the DC power generated by your solar panels to the AC power used by most household appliances.

That's a basic system, and of course any PV system can get much more complicated, with numerous PV panels set up in an array, multiple inverters, step-up transformers, and more. But a basic system can work with just those four elements.

A common size for a PV panel is 4' 5" by 2' 2", generating about 120 watts at peak performance, but realize that shadows, clouds, heat, and obstructions like leaves and debris on your PV panels can keep it from running at peak performance. So just how big a system will you need for your home?

That'll depend on how much space you have available for a solar array, the efficiency of your panels, and how much energy you plan to draw. Remember, your system doesn't have to offset all of your energy needs. Even a modest system can reduce your dependency on the grid and, at least during daylight hours, provide a level of power during outages.

To figure out your average current drain, check your utility bills over the past 12 months. If you don't have copies of your bills, your utility company generally keeps this information available for you online. Sometimes a phone call is required, but it shouldn't take you long to find this information. Average your yearly consumption (in watts) to find a monthly average, then divide by 30 to figure out the rough amount per day.

Now, decide what you want to power with your solar panel or array. You'll need to know the load, or the amount of energy that each appliance pulls. So let's say you want to power your refrigerator (800 watts), two lamps with fluorescent bulbs (say, 20 watts each), and a 100-watt ceiling fan. 800 + 40 + 100 = 940 watts of energy you'd want to cover.

Then it's a simple matter of installing a solar power system to cover those items. And you'll even find that in many cases you generate extra power. For instance, that refrigerator isn't running all the time, only when it's cooling. When it's just sitting there during a sunny day, the extra power can be conserved in your batteries or sent back to the grid.

This is, obviously, a very simplistic outline of a home-based solar power-generating system. You'd definitely want to talk to experts before doing an actual installation, both to get more detailed information and to find out what rebates and incentives are out there for you.

But you don't need an acre of space-age panels to join the solar revolution. Just be willing to become more energy aware and realize that even small contributions can make a huge difference.