Many people interested in solar energy wonder what impact their roof direction will have on solar efficiency and power. Sunlight angles throughout the day and the prevailing weather conditions at a given time of the year all factor into the answer to this question. Ensuring the proper placement and orientation of solar panel systems is a large part of the analysis that we at Eon Tech do for you as part of our free savings report.
So, what’s the best direction for solar panel systems? Generally, the optimal direction for a solar panel system largely depends on your geographic location. In regions located in the Northern Hemisphere (above the equator), solar panel systems work best when installed in a south-facing orientation. Conversely, in the Southern Hemisphere, solar panel systems generate maximum power when facing north. This orientation maximizes exposure to sunlight, aligning with the Sun's position in the sky.
Achieving optimal solar panel placement involves multiple factors, and there's no one-size-fits-all solution. Latitude, topography, roof pitch, roof orientation, and time-of-use policies are just a few of the many variables that influence the ideal placement of solar panel systems.
By examining these factors in the context of Montana and Idaho's unique geographic and climatic conditions, we can determine the most effective approach to solar panel placement for optimal energy generation and efficiency in these states. Additionally, we'll examine how the choice between roof-mounting and ground-mounting can impact solar panel efficiency in these regions.
Best Roof Angles and Directions for Homes in Montana & Idaho
As all of North America is in the Northern Hemisphere, the optimal direction for solar panel systems installed in Montana and Idaho is south. This orientation ensures that the solar panel modules receive maximum exposure to the sun's rays, resulting in optimal energy generation.
Another variable to consider is the roof angle or the optimal angle for the installation of solar panels. The latitude of your location determines the optimal angle. For example, for a home in Idaho where the latitude is approximately 44 degrees north, the angle of the solar panels is best set at 44 degrees. Likewise, the optimal roof angle for solar panels in Montana would be 46 degrees, which is the latitude of the state. If this is confusing, you can easily find the latitude of your exact location using a variety of online tools.
Having said that, the optimal angle for solar panels changes based on the season. During warmer, summer months with longer daylight hours and a higher solar peak, the optimal angle is typically 15 degrees less than your latitude. This adjustment allows the panels to capture more sunlight efficiently during the peak summer period.
Conversely, during colder, winter months when the sun is lower in the sky and daylight hours are shorter, the ideal angle for solar panels is typically 15 degrees more than the latitude for a given location. This adjustment helps maximize solar energy capture during the winter season when sunlight is less direct. There are also ready online calculators for solar panel tilt available that help calculate the tilt based on a given time of the year.
Many residential roofs are indeed built at an angle of around 30 to 40 degrees to facilitate the efficient drainage of rainwater or snow. When planning the installation of a solar panel system on such roofs, it's essential to factor in this incline to ensure optimal performance and longevity of the solar panels.
Solar Panel Orientation Based on Time-Of-Use Policy
Time-of-use policies involve an electricity billing system where the cost of electricity per unit varies throughout the day based on the demand for electricity at different times.
According to the electricity companies and statistics in Montana, the average residential kWh rate is $12.43/kWh. The cost of electricity in the state isn’t uniform throughout the day, but varies during the day, averaging at $12.43/kWh. NorthWestern Energy, the largest of the 30 electricity companies operating in the state, implements a time-of-use policy with varying rates for off-peak, mid-period and on-peak hours.
Similarly in Idaho, the average cost of residential electricity is $11.12/kWh in Idaho, according to the electricity companies and statistics. Idaho Power, the largest of the 29 electricity companies in the state also has a fairly straightforward time-of-use policy.
Indeed, residents in Montana, Idaho, or any part of the country installing a solar panel system would typically aim to offset peak-time electricity costs by relying on solar power as much as possible, particularly during the hours when electricity costs are highest. Solar energy generated during these peak demand hours becomes particularly valuable, helping to reduce overall energy expenses.
Not surprisingly, the orientation and direction of the solar panel system are major factors in this endeavour. As the sun rises in the east and sets in the west, orienting your solar panel in the southwest direction enables the module to generate more electricity in the afternoons and evenings, using the light from the setting sun.
To easily determine the exact southwest direction for your home, you can utilize online tools such as the onlinecompass.app. By accessing the website on your mobile device, you can instantly identify the direction of north, south, east, and west, helping you orient your solar panels for maximum sunlight exposure.
The Global Monitoring Laboratory serves as a valuable tool for determining the position of the sun in the sky for any location on Earth, utilizing latitude and longitude coordinates. Through its solar calculator, the laboratory generates daily and annual reports on key solar metrics such as sunrise and sunset times, solar declination, and solar noon—the time when the sun reaches its highest point in the sky.
By leveraging the location-specific data provided by the Global Monitoring Laboratory, homeowners and businesses can strategically adjust the orientation of their solar panels to maximize energy generation during peak-demand periods when electricity costs are highest. This allows them to optimize their energy savings and financial benefits while minimizing reliance on grid electricity during expensive times of the day.
Ground-Mounted Solar Panel Systems – Yay or Nay?
An often-used alternative to roof-mounted solar panel systems is ground-mounted modules wherein the solar panel systems are installed not on the roof but on the ground of a property. The panels can be installed using a standard ground mount having many anchors or stands to support the panels in a racking-table type of structure. Alternatively, a single pole mount system is erected which connects to the rails to mount the solar panels.
Topography presents a significant challenge for ground-mounted solar panel systems. Factors such as dense vegetation, tall trees casting shadows, or nearby high-rise buildings can obstruct sunlight and diminish the efficiency of the solar panels. As a result, ground-mounted systems may require clearing and levelling of the surrounding area to minimize shading and maximize energy generation.
Solar canopies have emerged as a revolutionary concept in parking lot design. These canopies feature solar panels installed on their surface, providing shade for parked cars while simultaneously generating renewable energy. Some solar canopies are equipped with carports, allowing electric vehicles to charge using the energy generated from the attached solar panel modules.
Pros of Ground-Mounted Solar Panel Systems:
- Freedom of Placement: Ground-mounted systems offer flexibility in orientation, elevation, and placement. This freedom allows for optimal positioning of the panels to maximize sunlight exposure and energy generation. In contrast, roof-mounted systems are often constrained by the available roof space, angle limitations, and structural considerations.
- Bypass Roof Issues: Ground-mounted systems bypass common roof-related issues such as weak structure, uneven roof surfaces, design limitations, and limited space. This eliminates the need for costly roof repairs or modifications to accommodate solar panels.
- Higher Energy Generation: Ground-mounted solar panel systems can be perfectly aligned to maximize sun exposure and generate high volumes of energy without any limitations such as roof design.
- Ease Of Maintenance: Ground-mounted panels are typically easier to access for cleaning and maintenance compared to roof-mounted panels. You can easily inspect and maintain ground-mounted systems without the need for specialized equipment or safety precautions associated with roof access.
- Expansion Potential: Ground-mounted systems allow for easier expansion if you wish to increase your solar energy capacity in the future. You can simply add more panels to the ground array without being limited by roof space or structural considerations.
Cons of Ground-Mounted Solar Panel Systems:
- More Expensive: Ground-mounted solar panel systems typically entail higher costs due to the need for additional installation hardware, labour, concrete foundation work, and potential permits and adherence to zoning laws. These factors contribute to the overall expense of the system.
- Higher Risk of Damage: Ground-mounted systems are more susceptible to various forms of damage, including wildlife attacks, theft, accumulation of dust and debris, and potential vehicular accidents. In contrast, roof-mounted systems are generally more protected from such risks and are designed to withstand weather-related damage.
- Aesthetics: Ground-mounted solar panel systems are not as discreet as roof-mounted systems and can detract from the aesthetics of your property. They occupy significant space and may require you to sacrifice open yard space, tall trees, or garden areas, impacting the overall visual appeal of your home.
- Demands Valuable Real Estate: Ground-mounted systems occupy valuable space that could otherwise be utilized for other purposes, such as constructing and renting out a garage, subletting a parking spot, or cultivating vegetation. This limitation may pose challenges for homeowners looking to maximize the utility of their property.
Conclusion
Indeed, various factors converge to influence the optimal installation of solar panel systems. By taking these factors into account, homeowners can effectively plan and execute the installation of solar panel systems to maximize energy generation, reduce overall energy costs, and contribute to a more sustainable energy future.
Reach out to us at EonTech to curate an optimal solar panel placement and installation plan that is best suited to your property, its location and its surroundings.