Latest articles by The Solar Nerd

Keep up to date on industry news and articles relevant to green living and the solar homeowner.

Example of polycrystalline and monocrystalline solar panels.
Which type of solar panel is best: monocrystalline or polycrystalline?
When it comes to buying solar panels for your home, there isn’t a lot that obviously differentiates one solar panel from other. If you buy a car, there’s dozens, if not hundreds of different features, styles, and add-on options that you can take into account. But with a solar panel, there’s really only a handful of characteristics that make one product different from another. One of these is the type of material the individual solar cells are made of.
Example of an AC module (Courtesy Panasonic)
What is an AC solar panel?
Solar panels are magical things that turn sunlight into electricity. The electrons that flow out of a solar panel move in a steady stream, known as direct current (DC). But because Nikola Tesla and George Westinghouse triumphed over Thomas Edison in what is now called The War of the Currents (they even made a movie out of it!) we use alternating current (AC) in our homes instead of DC. This means that the DC electricity generated by solar panels needs to be converted into AC before your home can make use of it.
Photo of a lightning strike.
Do solar panels increase the risk of a lightning strike?
There’s a lot of myths when it comes to lightning, such as lightning never striking the same place twice, or that using an umbrella in a storm puts you at greater risk of being hit by lightning. It’s understandable: lightning is a mysterious force of nature to many, and it’s also destructive, causing over $1 billion in property damage in the United States every year. When it comes to solar panels, there’s one persistent myth, which is that putting solar panels on your home can actually attract lightning to your home.
What is a PERC solar cell?
If you’re a homeowner who is comparing solar panels, there are really only a few features that obviously differentiate one panel from another, and efficiency tends to be one that manufacturers place front and center. Solar panel efficiency refers to how much light a solar panel converts into electricity. The higher the efficiency, the more electricity you’ll get from the panel for the same amount of light. For a rooftop deployment with limited space, this can be a very important feature.
Photo of an electricity transmission tower.
Is net metering unfair to non-solar homeowners?
Net metering is an important policy that gives solar homeowners full credit for any solar electricity they send into the grid. But many utilities want to end the policy, claiming that it’s an unfair subsidy that raises the cost of electricity for non-solar homes. More than that, electric utilities claim that solar net metering is a subsidy for relatively rich homeowners who can afford to go solar at the expense of lower income people who can’t afford to put solar panels on their house, or don’t have that option because they’re renters.
Photo of two people carrying American flags.
Definitive list of American made solar panels (2019 edition)
One of the great things about the green energy revolution is that it has created a rapidly growing job sector. In 2019, more than 240,000 people were employed in the solar industry across the United States. Many of these are solar installation jobs, but also solar is one of the sectors where domestic manufacturing is growing. If you’re thinking of going solar in your home and want to support American manufacturing, you might be wondering which solar panels are made in the US.
Do solar panels keep your roof and attic cooler?
If you live in a hot climate, it’s likely that air conditioning is your largest energy consumer. Photovoltaic panels make a lot of sense in these climates, because hot climates also have higher solar energy potential. After all, if the sun is making your house hot, why not also use the sun to generate electricity to keep it cool? But in addition to the active energy generation that solar panels provide, they can also provide another benefit by passively shading your building, possibly helping to reduce the temperature of your home and reducing the amount of time that your air conditioner needs to run.
Photo of a solar panel
Highest efficiency solar panels in 2020
When you’re shopping for solar panels, one of the things that manufacturers usually tout is efficiency. A high efficiency panel turns more sunlight into electricity than a lower efficiency panel, which means a solar homeowner can get more out of their limited rooftop space. So if efficiency is a good thing, that must mean that you should shop for the highest efficiency panels you can get, right? No, not always. If you’re in a situation where it’s important to maximize your power generation - like if you have a small roof - then efficiency could be very important to you.
Photo of a Sunny Boy inverter
Emergency backup power with the SMA Sunny Boy inverter series
If you have a home solar system, it won’t keep your house powered in a blackout unless you have a battery system. This is because solar inverters have a feature called anti-islanding. A solar inverter converts direct current (DC) power from solar panels into alternating current (AC) that your home and electric grid use. AC power has a frequency of 60 hz in North America. In normal operation, your solar inverter “listens” for power from the grid, and synchronizes its AC output to that of the grid.