Latest articles by The Solar Nerd

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

Photo of rain on a rooftop. (Credit: Gary Cole/Unsplash)
Did solar panels cause your roof to leak?
Most solar homes and small business use rooftop-mounted arrays. This is cheaper than ground-mounted panels, but carries a small risk of roof leaks. Solar equipment manufacturers make it as easy as possible to install solar panels on a roof without causing leaks, but there is still significant skill and training required to do the job properly. Even with the best equipment, a bad installation can cause your roof to leak. Sometimes, the leaking won’t be obvious until a few months or years after the work is done.
Photo of a mobile home.
Can solar panels be installed on a mobile home?
Mobile homes, also known as manufactured homes, are a popular housing choice in the United States. According to recent data from the US Census, over 100,000 new manufactured homes are sold every year. Add this annual new stock to the existing stock of manufactured homes, and you have a large inventory of houses that are potentially great candidates for solar. However, many people might assume that manufactured (also known as mobile) homes are not suitable for solar installation.
Photo of a house with all-black solar panels.
Do you need to upgrade your electrical panel for a solar installation?
Your home’s electrical panel is often an under appreciated piece of equipment. You probably don’t think about it until something goes wrong. However, you might need to take a closer look at your electrical panel if you decide to install solar panels on your home. Depending on the capacity of your electrical panel and the size of the solar array you install, the panel might need to upgraded. According to HomeAdvisor, the typical cost of a panel upgrade can be anywhere between $500 to $2,000.
Illustration of a person falling down a manhole. (Saepul Bahri/Vecteezy)
Sunrun PPA contracts: problems you need to know about
I’m not a big fan of leases and power purchase agreements (PPAs). It’s a topic I’ve written about extensively. While usage of PPAs has been dropping over the past decade, they still were 28% of the residential market in 2021 according to Berkeley Lab. Sunrun, the biggest solar installer in the country, is responsible for a large part of that market share. While Sunrun offers a variety of payment options including purchases, monthly leases and PPAs are a main focus of their business strategy.
Photo of Mars Helicopter with dusty solar panels (NASA/JPL-Caltech)
How much does dust effect solar panels?
No humans live on Mars yet, but several robots have. It’s really dusty on Mars, but in spite of that, the solar powered Opportunity rover lasted for 15 years. There’s no rain on Mars, and Opportunity didn’t have a way to clean its panels, so there were times when its power output was severely degraded. With the help of Martian breezes that would blow dust off its panels, Opportunity managed to generate enough power from its solar panels to far exceed its planned 90 day mission.
The disappearing polycrystalline solar panel
Most solar panels on the market today as made with silicon. There are two types: polycrystalline and monocrystalline silicon. To make monocrystalline solar cells, a single large crystal is grown. In contrast, polycrystalline silicon is made from small crystals that are formed into a larger ingot. With both types, the silicon is sliced into thin wafers to make individual silicon cells. Growing a large crystal of silicon is a more difficult process, which is why monocrystalline solar panels have traditionally been more expensive.
sunny window
Using solar for home space heating: questions answered
If you’re interested in a heating a whole house with solar power, that’s a pretty big topic. There’s a few ways solar can provide heat, from photovoltaics that power a heat pump to solar thermal panels that capture heat directly. You can check out my article on solar heating if you want to get into the details. However, I’ve noticed that there’s consumer interest in heating just a single room with solar power, and even some products marketed for this purpose.