by Justin Gray
All about Solar Power (FAQ)
We receive a lot of questions regarding Solar Panel set-ups, the Solar ePower Cube 1500, Solar Panels, Solar Chargers (Dex, Solo) and our other solar products. Below is a list of the most common questions.
What are solar panels?
Also known as “Solar Modules”, Solar Panels contain many photovoltaic (PV) cells wired together that take in the Sun’s light and convert it into usable DC electricity.
Solar Cell: One Photovoltaic cell.
Solar Module: Two or more Photovoltaic cells connected together.
Solar Array: Two or more Solar Modules connected together.
What are they made from?
Most photovoltaic solar cells are made of Silicon films and the completed solar panel is commonly covered in a protective glass.
How do they work?
Keeping it simple, the Sun’s rays (photons) hit the solar cells and dislodge electrons from the silicon film. These negatively-charged free electrons are collected and sent through the solar panel’s wiring to your battery for storage.
What is the wattage of the solar panel mean?
Solar panels are rated in watt-hours (Wh). If a solar panel is labeled as a “100 Watt Solar Panel”, it means under ideal conditions that panel can produce 100 watts of electricity an hour.
Are Solar Panels efficient?
Solar Panel Efficiency is defined by how much energy from sunlight can be converted into usable electricity (100% would be completely efficient). As a general rule, low efficiency cells are around 6% whereas high efficiency cells are about 25%.
Why are Solar Panels so “inefficient”?
Efficiency has many factors: type of solar cell used, proximity to the sun (latitude), climate, etc. We’ve come a long way from the start of less than 6% efficiency; we will continue to see efficiency ratings get better with time.
Should I buy Solar products or is it a passing phase?
Solar products are definitely here to stay. As more consumers and businesses invest into solar goods, the technology will continue to grow and efficiency will continue to rise as better techniques and materials are produced. They are becoming lighter, smaller, and more efficient with each passing day.
Will a solar panel charge my device?
This depends on the device being powered and the output of the solar panel. As with any electrical device, you need to know its maximum wattage requirement and pair it to the appropriate power source. For smartphones, #Camplites, and other small USB-powered electronics, our 6W and 12W Solar e Panels are a perfect choice for charging them.
How much power can a solar panel output?
There are a lot of factors that affect how much power a Solar panel can produce (see efficiency). To know the power output of a specific panel, take a look on the panel as the specifications are usually printed on the back or you can contact the manufacturer directly.
Are there different models of Solar Panels
Yes, there are 3 major types: Monocrystalline, Polycrystalline, and Thin-Film Solar Panels. Around 90% of Solar Panels today are made from some variation of silicon.
Are Solar Panels Waterproof?
Most large solar panels are sealed to some degree. If they are manufactured to be used outdoor year-round (like roof-top panels are), then they are made to be weather-proof (all types of rain, usually snow, etc.). Our portable Solar ePanels are water-resistant and can withstand light rain, condensation and splashes; while our larger panels are rated as weather-proof.
Can solar panels be directly wired to my device (inverter, sump pump, or other 12V powered appliance)?
The short answer is “yes”, the long answer is “no”. Even with a solar charge controller, the output of the solar panel is not constant. This is due to environmental conditions: heat, weather, clouds, sun intensity, etc. Conceivably, you can power an appliance directly from a solar panel, but the power supply to the appliance will not be constant or consistent. An ideal system would include batteries (as they supply constant and consistent power): where the solar panel charges the batteries, and the appliance is powered directly from the battery.
What is a solar charge controller?
A solar charge controller is a device that regulates the electrical current coming from the solar panel, monitors the battery’s voltage, and prevents overcharging of the battery. Charge controllers are rated based on their maximum input amperage.
What is the difference between PWM and MPPT Controllers?
A PWM or “Pulse-Width Modulation” controller is the most common and widely used controller type. MPPT or “Maximum Power Point Tracking” controllers are able to optimize the output of the solar panel and extract an additional 15-30% more power than a PWM controller. Although considerably more expensive, the increased efficiency and power collection is usually worth the price for large, permanent systems.
Do I need a charge controller?
For smaller solar panels used for charging portable electronics, solar controllers are not necessary (but a diode is usually in place to prevent reverse-charging). Generally, for any solar array larger than 5A, a solar charge controller will be needed.
What size solar charge controller do I need?
To determine what size controller you need, there is a simple formula. Take the total amount of watts in your array, then divide that number by your battery voltage to get amps. Add 25% to that number, and you’ll have the size charge controller that you need (always round answers up).
For example, you have 2 solar panels that are 120 watts each (2 x 120 =240 watts). Now divide that number by your battery voltage (12V is the most common) and you get 240/12=20 amps. Add 25% to that number (to allow for cold temperatures) and you have 20 + 25%= 25 amps. For this example, a 12V, 25A charge controller would be needed.
What size wire from the solar charge controller to the battery do I need?
To determine what size wire you need, look at the chart below. Find the size controller that you have (in (A)mps) and look at the corresponding wire gauge (AWG) listed. This chart takes in account the "worst case scenario" of a full-load solar panel in hot temperature conditions based on a 10-foot or less run.
Controller Amperage - Wire Gauge
10A - 14AWG
20A - 12AWG
30A - 10AWG
40A - 8AWG
60A - 6AWG
80A - 4AWG
100A - 2AWG
We’d be happy to answer any question that you have regarding our products and your set-up, email us at CustomerService@Wagan.com or call 1.800.231.5806!