So you’ve decided to make the switch to solar power. You’re in luck. The costs of solar systems have dropped dramatically in the last 10 years while the efficiency of solar panels has increased. There has never been a better time to install a solar system for your home. We can help you find the one that meets your needs and give you a breakdown of the components necessary to make the switch.
As you consider adding solar panels to your home, you’ll want to think about where you’re going to place them. South-facing panels are preferred over west-facing panels because they get more light as the sun’s path shifts throughout the year. However, research suggests that the most efficient placement is at 219 degrees, which is almost right between south and west.
When you are deciding on what solar panels to use, there are two types that are the most common: polycrystalline and monocrystalline.
- Monocrystalline panels are of higher quality. They cost more, but they produce more energy, so you need fewer panels. They are typically 15 to 20 percent efficient. Monocrystalline panels also last longer, with many manufacturers offering a 25-year warranty.
- Polycrystalline panels are less expensive. They tend to be 13 to 16 percent efficient. You will generally need more panels to get the same energy output.
One way to figure out the best deal on a solar panel is to determine the dollar-per-watt ratio. Take the cost of the solar panel and divide it by the watts it produces. For example, the Renogy 260 Watt panel costs $274.99. Divide $274.99 by 260 watts to find that it costs about $1.06/watt. On the other hand, the Renogy 310 Watt panel costs $294.99. Divide that by 310 watts, which equals about $0.95/watt.
Mounting systems come in different forms, from tracks to poles to fixed, roof-mounted racks. There are three essentials to be aware of when mounting a system on your roof:
- The panels must be at right angles.
- There should be enough space under the panels for air to freely flow around them.
- Shadows from trees or other buildings should not fall on the panels.
Tracks-based roof mounting systems are one of the most common. A kit comes with the rails, clamps, flashings, joiners, and brackets. They range from the 12-Panel Roof Mounting Kit Portrait at $879.95 to the 2-Panel Roof Mounting Kit Landscape at $279.95. When you measure your roof to figure out which kit sizes you’ll need, consider whether you want to lay them upright or sideways. This will determine whether you need a portrait kit (upright) or a landscape kit (sideways).
Charge controllers have a couple of jobs. The first is to prevent your batteries from overcharging. The second is to stop the battery bank current from heading in the wrong direction back to the solar panels at night or on cloudy days to avoid drain on your battery bank.
There are two main types of charger controllers: Pulse Width Modulated (PWM) and Maximum Power Point Tracking (MPPT). PWM charge controllers are older technology that are typically used for smaller systems. MPPTs deliver up to 25 percent more power than a PWM. Prices for charge controllers range from $22.95 all they way up to almost $1,000. The model you get largely depends on what you need for your system: how big it is, how efficient you need the system to be, etc.
If you’re going off the grid or you want power, a battery bank is essential. What batteries you get will depend on how much energy you want to store. Typically, solar energy systems use one of two types of deep-cycle lead acid battery:
- Deep-cycle flooded lead acid (FLA) battery: These are the most common type of battery you’ll see with solar power systems. They cost less, have a long life, perform well, and are easy to maintain.
- Deep-cycle valve-regulated lead acid (VRLA) batteries: These use absorbed glass mat (AGM) technologies. They are more flexible on where and how they’re installed. AGM batteries are maintenance-free and don’t degrade as easily, making them the safest lead acid batteries. They also hold their charge better, even when not used daily, and are highly efficient, charging and discharging at 100 percent amperage.
It may take 100 or more cycles for batteries to reach their full capacity. This is completely normal and is to be expected. Batteries range from around $90 up to about $1,650. You’ll need to calculate how many batteries you need to achieve your energy goals and then create a bank of batteries to store that amount of energy. If you’re living off the grid, you’ll also want a backup generator in case you have an unusual number of days with no sun.
The energy that comes in through the solar panels is DC, but your home uses AC energy. The inverter converts the DC energy to AC, so it’s usable by your electrical system. There are three types of inverters:
- Microinverters: These are located near a solar power and convert the electricity produced by one panel. This helps in case shade falls over one of the panels in an array, or if one of the panels malfunctions.
- String inverters: These are highly efficient and robust while being inexpensive, but they don’t have panel-level monitoring and there’s a potential safety hazard because of their high voltage.
- Central inverters: Best used with large arrays, these are more consolidated and are less expensive per watt. They’re highly efficient and fairly easy to install. If one panel in an array fails, the whole system could fail.
Whatever style of inverter you get, you’ll want to get a true sine or pure sine inverter if you need to run your whole house off of the energy your solar panels capture. A modified sine wave power inverter is fine for smaller systems. For whole households, look for inverters that have 4,000 watts or more, like this Invert-It inverter for $1,292.95. The type you get will depend on the size of your system and your home.
Once you have these essential components in place, you’ll be well on your way to living the dream of renewable energy.