Best solar panel direction for every goal
Here is a summary of the best solar panel direction for every use case.
|Your goal||Best direction|
|Maximize solar power output||South|
|Take advantage of net metering||South|
|To pair with battery/reduce grid reliance||South|
|Minimize impact of high Time of Use (TOU) rates||South and southwest|
Explanations are provided below.
Best solar panel direction overall
Overall, facing solar panels south is the best option. In almost all situations, positioning your solar panels south will result in the greatest electric bill savings and the shortest payback period for homeowners.
Your ability to benefit from net metering, optimize solar production, and make the most of battery storage are all increased when your solar panels face south, which also enhances the economics of solar in other ways.
Below, we go over each of these causes in more detail.
South is best direction to maximize solar panel output
When solar panels are facing south in the Northern Hemisphere, where the United States is located, they will produce the most electricity.
This is due to the fact that throughout the year, the sun shines straight over the Equator on average. If you’re north of the equator, you’ll get the most sun exposure by facing south toward it. The Sun passes across the southern half of the sky all year long in all areas north of the Tropic of Cancer (23.4°N Latitude), which covers the entire U.S. mainland.
In the United States, solar panels positioned south will, therefore, always face the sun.
During the summer solstice, the sun’s path goes as far north as it can go, passing straight over the Tropic of Cancer, which is 23.5° north of the Equator (June 21). The sun always shines to the south for us because the whole U.S. mainland lies north of the Tropic of Cancer.
South is best for homes with net metering
The optimal orientation for your solar panels if you live in an area with full retail (1:1) net metering is south.
This is so that, if 1:1 net metering is available, you may most effectively reach your desired level of solar output, regardless of when that power is generated.
I’ll explain. South-facing solar panels generate the greatest power overall, but they also generate the most during the noon. Your usage is normally at its lowest during the middle of the day, thus there will be a large amount of extra power generated. With net metering, having excess electricity is advantageous since you may export it to the grid and receive bill credits for the full retail value.
In other words, it won’t matter if you produce solar power if you live in a place with 1:1 net metering. Instead, you’ll want a solar power configuration that generates all of the electricity you need while costing as little as possible; you can do this by facing your solar panels south.
South is best with battery systems
If you intend to build a battery storage system like the Tesla Powerwall or sonnen Eco, south-facing solar panels are the best option.
This is so that you can produce as much electricity as you can during the day if your system uses batteries. If you face your solar panels south, you should be able to generate plenty of extra electricity to recharge your battery while still meeting your daytime energy needs. After that, you can use your battery to power your home during grid outages, overnight, and at peak periods.
You may maximize your energy self-consumption by combining south-facing solar panels with a battery option. This implies a lesser reliance on the grid or possibly complete independence from it.
South to south-west is best for TOU rates
If your utility uses Time of Use (TOU) billing, it is recommended to position your solar panels between south and southwest.
In areas with TOU billing, utilities typically charge a higher rate for electricity later in the day, or a “peak rate,” starting at 4 o’clock. Your solar power generation is more useful at peak times since grid electricity is more expensive.
South-west oriented solar panels produce more energy later in the day because they are exposed to more light from the setting sun. However, there is a cost associated with this: a reduction in the day’s total solar output.
Therefore, depending on how high peak rates are in comparison to off-peak rates, the ideal orientation will be determined. The best direction will be slightly west of south if peak rates are twice as high as off-peak rates. However, the solar panels should face southwest if peak rates increase to three times the off-peak rate (or greater).
The ratio of TOU peak rates to off-peak rates determines the best orientation for solar panels. The optimal orientation is depicted in the left image when peak rates are twice the average rates, and in the second and third images when peak rates are tripled and quadrupled, respectively. Picture source: Aurora Solar
Using various TOU rates available in California, solar software designer Aurora Solar examined the best orientations. The optimal direction was somewhere between south and south-west in every case that was examined. San Diego Gas & Electric’s TOU-DR-SES, which has reduced off-peak rates but a very high peak pricing, was the location that was closest to the southwest.
The best orientation for you, given TOU prices in your location, can be determined when a solar contractor examines your roof.
Enter your address here for an estimate if you’d like to examine the costs and savings associated with going solar with the roof you currently have after accounting for utility prices in your area.
How much does solar panel direction affect output?
Solar panels will produce their most power when they are pointed true south in the United States (180 degrees azimuth from solar noon). If you turn the solar panels in any other way, their production will decrease.
|Direction||Typical output loss|
Which direction, north, south, east, or west, do you prefer? The south is undoubtedly the answer when it comes to solar panels. The diagram provides rough estimates of the production losses brought on by mounting your solar panels in a direction other than south.
Panels facing southwest or southeast
In general, solar panels installed on a roof with a southwest or southeast orientation will generate around 8% less power than identical panels installed in the same climate on a roof with a south orientation.
Panels facing east and west
A standard pitch roof with panels facing east or west will yield about 15% less output than a normal pitch roof with panels facing south.
Panels facing north
A typical pitch roof with solar panels facing north, or away from the sun, will produce about 30% less energy than a roof with solar panels facing south.
Explained: Impact of direction on solar panel output
Solar panels turned away from true south typically have production losses of less than 30%, although in rare circumstances, losses of around 60% could be observed.
The precise drop in energy production is determined by three factors:
- Distance from south: the angle at which the panels are tilted against true south
- Your latitude: How far north is the location of your residence
- The pitch of your roof: This establishes the angle at which the solar panels are mounted.
Distance from south
It should go without saying that the loss in energy production increases with increasing turn away from the south. Thus, a turn to the south-west will result in a slight drop, a move to the west will result in a medium drop, and a turn to the north will result in the largest drop.
In terms of latitude, the greater the reduction in energy production when you shift away from south, the further north you are. If all else is equal, a home in Miami, FL will see a smaller production loss from non-south alignment than solar panels in Seattle, WA.
Regarding roof pitch, non-south facing solar panels will produce less power the steeper your roof is. Turning solar panels from south to north, for example, would result in a 16% loss for a roof in Charlotte, North Carolina with a pitch of 2/12 (9.5*); while, a roof in the same area with a steeper pitch of 4/12 (18.4) would see a far bigger reduction of 29%.
What if your roof doesn’t face south?
Your rooftop solar energy system should ideally face south for best efficiency, with a few of the exceptions mentioned above. This isn’t always possible, of course, as many households don’t have roofs that face that way!
Fortunately, this is not a deal-breaker. Many households who don’t have south-facing roofs had solar panels installed, and they’re saving a ton of money on their electricity bills.
Here are some alternatives for home owners without roofs that face south:
Install solar panels on your roof anyway
You can add more solar panels to make up for the reduced amount of sunlight. Solar panels themselves only make up a small fraction of the expenditures of a solar panel installation; you should be able to add a few extra panels without significantly raising costs.
When they don’t have a portion of their roof that faces south, most homeowners opt for this alternative.
Install a solar array on the ground
In your yard, you can also put in a ground-mounted solar power system. Although it costs cheaper, this does take up a lot of yard space compared to building racks on your roof or hanging them on a wall.
The simplicity of maintenance is one of the best features of ground-mounted solar panels. You can remove snow or leaves from them without going up on your roof.
By providing constant, direct exposure to the light throughout the day and all seasons, solar panel tracking systems can increase a system’s output. Axis trackers use about the same amount of area as stationary systems while producing more electricity.
Utilize solar panel trackers
Consider solar panel tracking systems if your budget allows. By assuring steady, direct exposure to the light throughout the day and all seasons, they can increase a system’s production. Axis trackers use about the same amount of area as stationary systems while producing more electricity.
Solar trackers are costly, it’s vital to remember that. The cost of a single-axis tracking system like the Smartflower, which can provide the same amount of power as a normal 4 kW fixed solar panel system ($2.85/watt), is $20,000, or nearly twice that amount.
Which direction is ideal for solar panels to face? Ratings