Why Do Solar Panels Have To Face South?

The conventional idea is that solar panels should face south. This is because, while we complete our yearly orbit around the sun in the Northern Hemisphere, the sun is always in the southern region of the sky. As a result, the current best practice has always been to arrange solar panels facing south in order to gather the most amount of sunlight possible.

In the solar industry, it’s common knowledge that these south-facing panels should be angled between 30 and 40 degrees. This angle fluctuates and is roughly equivalent to your home’s latitude (how far north you are in relation to the equator).

This angle specificity is intended to ensure that sunlight strikes panels at a perpendicular angle, which provides the most energy. In the northern hemisphere, an angle along these lines also makes it easier for snow to slide off solar panels during the winter.

Some rooftops slope almost perfectly, allowing installers to mount the panels snugly against them while maintaining a fantastic angle for capturing the sun’s energy. Some rooftops are steeper than others, while others are level. There are many mounting techniques to help place your solar modules so that they can produce at their best, depending on the sort of roof you have.

Why is it necessary for solar panels to face south?

Overall, facing solar panels south is the best option. In almost all circumstances, placing your solar panels south over any other direction will result in the largest electric bill savings and the shortest payback period.

The economics of solar are improved by facing your panels south in three ways: it optimizes solar production, it maximizes your ability to use net metering, and it maximizes your ability to use battery storage.

South is best direction to maximize solar panel output

Solar panels facing south in the Northern Hemisphere, where the United States is located, will produce the most amount of electricity conceivable.

This is due to the fact that the sun shines straight over the Equator on average throughout the year. If you’re north of the Equator, gazing south will optimize your sunshine exposure. In fact, the Sun passes across the southern half of the sky all year in all places north of the Tropic of Cancer (23.4N Latitude), which covers the whole mainland United States.

In other words, solar panels facing south in the United States will be exposed to the sun throughout the year.

During the summer solstice, the sun’s path goes directly over the Tropic of Cancer, which is roughly 23.5 north of the Equator (June 21). Because the entire continental United States is north of the Tropic of Cancer, the sun shines on us all year.

Is it necessary for solar panels to face south?

The traditional idea is that a roof should face south for the best solar exposure. Though south-facing roofs receive the most direct sunshine, the message is that solar doesn’t have to be installed on a south-facing roof. The cost of energy and potential incentives will have a considerably greater impact on your solar economics than roof orientation.

Is it necessary for solar panels to face a specific direction?

The study discovered that solar-powered homes use less than half the amount of utility-provided electricity as conventional homes. However, they consume more from around 4 p.m. to midnight, contributing to the system’s peak demand, which occurs around 5 p.m.

When panels are pointed west, they produce 55 percent of their highest production in the hour beginning at 5 p.m. As a result, a 10-kilowatt system will produce 5.5 kilowatts. However, if you position them south to maximize total output, they only produce 15% of their peak power, or 1.5 kilowatts, when the electric grid most needs it.

Why aren’t all the panels pointing west? Because the roof is facing south, some homeowners have their panels facing south. While some solar panel owners receive time-of-use rates and are compensated by the utility in proportion to wholesale electric grid prices, many panel owners are unable to benefit from the higher value of electricity during peak hours because they are paid a flat rate, according to the energy analysts. As a result, the payment mechanism incentivizes the homeowner to commit fraud. The California Energy Commission recently announced a $500 premium for new west-facing installations. According to the study’s authors, a new solar installation is finished every 3.2 minutes.

Solar panels do not have to be aimed in one direction; instead, a tracker may be purchased that will pivot them like a sunflower during the day, ensuring that they constantly face the sun. A tracker can boost a panel’s output by 45 percent. However, installing trackers can cost hundreds or thousands of dollars, and buying a few extra panels may be a more cost-effective way to acquire the same amount of kilowatt-hours.

Is it possible to put solar panels facing west?

Because their owners desire to generate as much electricity as possible, most rooftop photovoltaic (PV) panels face south. However, according to a recent analysis, moving more PV panels to the west will provide electricity at a time when it is far more beneficial to utilities, lowering the need for utilities to purchase expensive power to meet peak loads.

Barry Fischer and Ben Harack write in an Outlier blog for Opower, a company that analyzes energy data for utilities, that most PV-equipped homes produce far more power than they consume during the middle of the day. The grid, on the other hand, desperately needs the extra power in the late afternoon.

Fischer and Harack said they examined Opower data from 25,000 solar homes in the western United States, as well as public data on 110,000 residential projects built in California since 2007.

“They claim that their statistical findings suggest a significant divergence between today’s solar panel landscape and the broader power system.

More west-facing panels would create more power in the late afternoon and provide utilities with a new reliable source of energy “a attractive alternative to adding more power plants to the grid

The Pecan Street Research Institute at the University of Texas at Austin came to the same conclusion in a paper released last December. However, that research was based on a far smaller sample of only 52 residences.

Lots of midday output

Because the panels create more electricity than the homes need during the sunniest portions of the day, an average of 93 percent of solar-equipped households export electricity to the grid. The authors tracked electricity exports in 25,000 western households from approximately 8:00 a.m. to just before 4:00 p.m. on one particular day, a hot day in May of this year.

Following that, solar homes used more energy than non-solar ones (see graph in Image #2 below). “Wondering why solar households’ use of grid electricity jumps considerably above average after the sun goes down?” the authors ask. It’s probably due to their owners’ higher energy needs: the average solar home in our database is 34% larger than the average non-solar home, 2.6 times more likely to have a pool, and 2.7 times more likely to enroll in an electric vehicle rate plan.

Between 11:00 a.m. and 1:00 p.m., the average solar home generates enough energy to power both itself and two non-solar homes.

Peak demand on the grid, on the other hand, occurs around 5:00 p.m., when the output of south-facing panels has dropped dramatically. Only 27% of solar households are exporting power to the grid by 4:00 p.m.; by 5:00 p.m., that number has dropped to 6%.

“Could solar households be more useful in meeting grid peak electric demand?” ask the authors.

The answer is unmistakably positive. And it looks that a tiny group of houses is leading the way.

Panels face south for a reason

According to the blog, only 9% of solar panels in California face within 10 degrees of straight west. When compared to south-facing panels, the total production of western-oriented panels is reduced by 10% to 20%, resulting in less electricity for households and lower net-metering earnings.

The peak production for west-facing arrays is 2:00 p.m., two hours later than for south-facing panels, according to the blog.

That is why some utilities are enticing homeowners to transfer by giving financial incentives. According to the study, some plans pay customers up to 35 cents per kWh for power generated late in the afternoon, compared to 12 cents per kWh for power exported to the grid at noon.

“Offering a handsome incentive for well-timed solar power (or well-timed usage reductions) can be a smart play for any utility seeking to avoid a painful alternative: paying notoriously high marginal costs to source electricity from ‘peaker’ power plants (e.g. 3 to 5x the normal price level),” according to the report.

“It goes on to say that an adequate time-of-use pricing scheme could allow west-facing systems to achieve attractive monetary returns despite their lower annual energy output.”

Our recent study of time-varying rates, particularly those that incentivize electric car charging at night, reveals that they can have a significant impact on customer behavior.

The California Energy Commission recently approved up to $500 in subsidies for the installation of west-facing solar panels.

Will solar panels operate on a roof with a northerly orientation?

A solar panel should ideally face true south in order to generate the greatest power. Roofs facing south-west and south-east are likewise considered highly efficient, but homes facing east or west lose about 15% of their efficiency compared to a south facing roof. In general, a north-facing roof is not recommended. Although most properties with a north facing roof will also have an opposite roof face, the layout of the building may prevent this.

Solar electricity can still be harnessed in buildings with a north-facing roof. Panels can be pitched against the roof’s slope, although this will detract from the roofline’s aesthetic appearance. Panels can also be put at ground level, although this requires avoiding places with a lot of shade.

Even a minor deviation from true north may be sufficient to assure efficient solar panels.

Can solar panels be installed on an east-facing roof?

The greatest sort of roof for solar panels is one that faces south, as solar panels generate the most electricity. Because south-facing roof panels receive the sun at its most intensity for the longest amount of time, they produce the greatest energy.

This isn’t to say that solar panels can’t be installed on east or west facing roofs. Even if your roof faces a different direction, you can still get the benefits of installing a solar array. Solar panels can be installed on east and west facing roofs, and they will still provide a significant amount of electricity throughout the day. An east-facing roof, for example, will receive more sunshine in the mornings, while a west-facing roof will receive more sunlight in the afternoons and nights.

As you can see, a south-facing roof provides the best solar panel orientation, with a potential savings of 194.41 in the first year. Meanwhile, a north-facing roof will save you money on your energy expenses, but not as much as a south-facing roof (92.35).

After 20 years, what happens to solar panels?

Solar panels, like most technology, will produce less energy with time. The degradation rate refers to the reduction in power production. The median solar panel degradation rate is around 0.5 percent per year, which basically indicates that the energy output of a solar panel will drop by 0.5 percent every year. 3 Your panels should still be producing around 90% of their original output after 20 years.

Is it possible to use solar panels on overcast days?

Photovoltaic panels can generate electricity from direct or indirect sunlight, but they are more efficient in direct sunlight. Even if the light is deflected or partially obscured by clouds, solar panels will continue to operate. Rain actually aids in the proper operation of your solar panels by washing away any dust or grime. If you live in an area with a strong net metering policy, extra energy generated by your panels during the day will be used to offset energy used at night and other times when your system isn’t running at full capacity.

Which way is the best for solar?

The general rule for solar panel placement in the northern hemisphere is that solar panels should face true south (and in the southern, true north). Because solar panels receive direct sunshine throughout the day, this is usually the greatest direction. However, there is a distinction to be made between magnetic south and real south. When a compass is used, the “south” represented is magnetic south, which points to the Earth’s south magnetic pole. Solar panels, on the other hand, must face solar or geographic south, or the direction that leads to the South Pole. By the same logic, if the solar panel is positioned in the southern hemisphere, it should face true north.

It may also be useful to have a tiny rotation away from due south, depending on how solar panels are employed. Solar panels for a residence, for example, should face somewhat south-west depending on their intended purpose. When these panels face due south, they capture more energy, but the energy is more beneficial later in the day. As a result, the solar panels are able to produce more electricity during peak hours. The panels may create more energy in the evening, when people are home and using more appliances, if they were pointed slightly south-west, in the direction of the setting Sun. The loss in total production is offset by the availability of electricity when it is most needed. During the morning and midday, most areas have enough electricity from other sources.

When solar collectors are used for heating and lighting, it is actually ideal to have them facing east, especially if they are in the form of fenestration like windows. Warming the house for the day necessitates the use of morning sunshine.

How do you determine a solar panel’s true south?

True south can be located when the sun is at its highest point. Generally occurring at 12 p.m., this time of day is also known as “solar noon. Using a few scientific and clever methods, you can find true south during this time.

By compass

True south follows the Earth’s axis rather than its magnetic poles. The Earth’s polarity, due to its tilted rotation, will lead a compass to point toward a magnetic North or South Pole that is many degrees off its axis. So, unless you know your magnetic declination, a compass will be useless in establishing true south.

Magnetic declination

The most accurate way to determine true south in relation to your home or business is to learn the magnetic declination of your location. To calculate true south, you’d need to know your latitude and longitude and utilize a compass. The National Oceanic and Atmospheric Administration (NOAA) now provides a website that can help you with this.

Find your shadow

Observing the direction your shadow points at solar noon is a great approach to rapidly compute true south. On a cloudy day, finding true south may be difficult; however, your expert solar power installer should be able to do so for you.