Solar Panel Placement- Should My Solar Panels Always Face South?

Even though placing solar panels on top of the roof is the most obvious thing to do when we want to install solar energy for our house, we rarely think about Solar Panel Placement. That’s because, In most situations, south-facing solar panels on a rooftop are the best location for placing your panels, and it’s always a given.

But, to truly understand a bit more about Solar Panel placement, you’ll have to read on and understand the nuances of the placement of solar panels. 

Solar Panel Placement and its effects
Sun Path and how Solar Panel placement affects the output

In short, here is the list of solar panel orientations for different situations

Maximize Solar Electricity + Storage UseSouth Facing
Maximize TOU production/ratesSouthWest Facing
Maximize Net Metering / ROISouth Facing

Basics of Solar Panel Placement

When installing solar panels in the Northern hemisphere (which includes the United States and Europe), you may have thought that you should always face your solar panels South[1]. 

Your solar installer will help you pick the perfect solar panel placement. You should feel entirely comfortable with their explanation of where and why. But in general, there’s one rule: if you’re in the U.S. or the other parts of the Northern Hemisphere, your solar panel placement should face true South. (If you’re in Australia or the Southern Hemisphere, the solar panel placement you should install is to face north) Placing your solar panel angle to face the South makes intuitive sense since it maximizes the sunlight a solar panel will get as the sun moves from one horizon to the other. Although the placement of panels is essential, a significant factor that gets maximum production is to ensure that your panels are also clean and free of any dirt or debris. People who use solar panels must clean their panels either by hosing them down with water or annually hiring Cleaning folks who can scrub down the panels using solar panel brushes to clean and wipe down any tough debris like bird poop or accumulated dirt.

However, it’s well-known that annual electricity production will be the highest with south-facing panels. In the same regard, it’s not well-known that west-facing arrays are much better at reducing peak loads in climates with air-conditioning that has driven peak demand like Austin. This was proven by a recent study there.

South Facing – Netmetering / ROI Benefits 

South Facing will be the best option if you’re looking to maximize your Return on Investment for the solar energy system. The reason being is South facing panels produces the most electricity generation overall. As a result, you’ll have maximum production from your solar energy system.

So during high noon, the production will be the highest. Still, it will also be the time of the day with the lowest consumption, which automatically means that surplus power will be sent back to the electricity grid, and every electron which is transmitted back to the grid will return bill credits equal to the retail value for which you buy the electricity, which is also called as Net Metering

So in this way, south-facing solar panels installed on your rooftop will maximize your Return on Investment (ROI) and have faster payback compared to any other location.

Battery Backup system – South Facing 

Battery backup systems are on the rage now, and their demand has skyrocketed in the past few years. The fact that coupled with climate change, the electric grid has become unreliable in many parts of the country, and as a result, solar energy storage is having a moment right now.

Eventually, these systems will become the staple of any solar energy system. Battery backup systems / solar energy storage systems do not come with solar panel systems and must be purchased as an add-on. Hence we would need to consider the effectiveness of the solar energy storage system when purchasing the combined package (Solar energy system + Storage system).

Such an integrated system would produce maximum power for the solar energy system. The solar storage system stores as much power as possible to be used at nighttime and reduce dependence on the Electricity grid.

The best option, in this case, would be to install solar panels on your south-side facing roof that will meet your daytime needs, generate surplus power when there is low consumption, and utilize that energy produced to charge up your battery. Hence, you can use your battery to use power during overnight and peak times, generally considered early evening hours (4–7 pm).  

As a result, a Solar panel + Storage system combination would be suited for Solar panels installed on the south-facing side of the rooftop.

TOU production/rates – Why SouthWest?

According to a recent study from Pecan Street Research Institute[2], a Texas-based entity has surveyed the best location for solar panels. The study concluded that West-facing rooftop solar panels produce 49 percent more electricity during peak demand than south-facing panels.

The research is the first to understand and evaluate the energy production of solar panels oriented in different directions. The study was done by Pecan Street Research Institute based on 50 homes in the Austin, Texas, area. The study had solar panels on the roof facing only south-facing, others at west-facing, and some had both of them included.

It concluded that South-facing panels produced a 54 percent peak reduction overall. In comparison, west-facing solar PV panels produced a 65 percent peak reduction. Fully 75% of the home’s electricity from west-facing systems was used, with only 25% sent back to the grid.

In the study, the data was normalized for a 5.5-kilowatt system. The panels turned to the West generated nearly 50 percent more electricity during peak demand hours than southern-facing solar panels. Homes with west-facing systems also produced slightly more electricity.

Those panels produced 37 percent compared to 35 percent for the south-facing panels in overall electricity use. Peak demand, which is 3 pm to 7 pm in Texas’s ERCOT territory, 84 percent of electricity in west-facing solar energy systems was used in the home.

Average daily generation profile (kW) from rooftop PV systems for south and west systems – Pecan Street Research Institute

Our Verdict: Point It West But Look At When You Use

To reduce peak load and put less strain on electricity distribution systems, west-facing PV systems may be more practical than south-facing systems, despite producing less total energy over a year. It’s qualitatively apparent that west-facing solar panels produce more electricity later in the day when the sun is setting in the West. However, having actual quantitative numbers helps convince homeowners to reorient solar panels depending on their electricity usage. 

Our verdict is that more solar arrays should be pointed West, not because they produce more power that way, but rather because, in many cases, the power they have is more readily used. Utilities and governments should structure their incentives accordingly. Before deciding on this, do some calculations and look at your electricity usage first.

Misconceptions abound. Since the Pecan Street Research Institute report came out, the media took the news. They promoted the false concept that west-facing roofs get more energy. On the other hand, utilities are misinformed in the other direction. CEO Brewster McCracken says that some of the utilities in his area don’t even offer incentives for west-facing solar arrays because “they don’t produce enough energy.” 

What’s Next?

For Pecan Street Research Institute, the next set of research will also include information about the roof’s pitch and the panels’ placement. It is a well-known fact that Solar panels on flat roofs produce the highest amount of electricity, but most homes in the U.S. have pitched roofs. Pecan Street will also look beyond the city of Austin in the next round of the study. CEO McCracken said they plan to include homes in Colorado, Dallas, and potentially California.

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