Solar Nerd articles about: System Design

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Photo of a north compass arrow
Can you put solar panels on a north facing roof?
If you live in the Northern hemisphere, solar panels will receive the most sunlight if they face south. (This is reversed in the Southern hemisphere, so if you live in Australia the preferred direction is north). If you’re a homeowner interested in solar, you might not have this option: maybe the south-facing part of your roof is interrupted by vents, skylights or gables, or is shaded by trees. West is usually the next best option (which generates electricity during the evening peak) followed by east.
Photo of a large house.
How many solar panels are needed to run a 4,000 square foot or larger house?
If you have a very large house, you probably have high electricity usage too, possibly making your home a good candidate for solar. If you’re curious about solar and want to find out how many solar panels you’d need for your home that is 4,000 square feet or larger, the most accurate way to find that out is to get a professional solar installer to perform an analysis. A quick but somewhat less accurate way is to read your monthly electric bill and use our solar calculator to determine what your power generation and estimated system price would be.
A photo of a garage
Can you install solar panels on a detached garage or shed?
The average size of a home solar installation in the United States is around 6 kilowatts, which is about 17 high efficiency premium solar panels, or more if you go with a cheaper panel. That many solar panels takes up a lot of space, and you would need a large available roof area to accommodate them. But sometimes, your roof might not be ideal for solar. It might be oriented east-west (which generates less power than a north-south orientation) or, more commonly, you might have shading from nearby trees or buildings.
Photo of a nice house with solar panels.
Can I face my home solar panels east?
To generate the maximum electricity from your solar panels, you want them pointed south (if you live in Northern Hemisphere), but sometimes you don’t have much of a choice. Most homeowners mount their solar panels on their roof and consequently only have a couple orientations to choose from. (This is also known as azimuth, where 0° means pointing north and 180° is south.) Solar panels will work if you face them east: on average, east-facing solar panels will generate about 80% as much electricity as they would if pointed directly south.