Table of Contents
- Brief Overview of Solar PV Technology
- Understanding Roof Orientation and Solar PV Efficiency
- Is It Possible to Fit Solar PV on an NW-Facing Roof?
- Benefits of Installing Solar PV on an NW-Facing Roof
- Factors to Consider Before Installation
- Make an Informed Decision on Solar PV for Your NW-Facing Roof
- Get Expert Guidance from EvoEnergy
It is commonly known that solar panels should be installed with a south facing orientation in order to maximise it’s operational output. So if this is the case, then does that mean that solar panels shouldn’t be installed on a NW facing roof?
Key Takeaways:
- Installing solar PV on a northwest-facing roof results in a 30-40% decrease in energy generation compared to south-facing installations.
- Roof tilt, ideally between 30-40 degrees, helps improve the efficiency of solar panels even on NW-facing roofs.
- Shading as little as 10% can lead to a significant reduction (up to 50%) in energy output from solar PV systems.
- Additional equipment like microinverters can help optimise energy generation but may increase installation costs by 10-15%.
- Solar PV systems on NW-facing roofs still offer energy savings, particularly in the summer months when daylight is longer.
Brief Overview of Solar PV Technology
Solar photovoltaic (PV) systems are designed to convert sunlight directly into electricity using semiconductor materials, typically silicon. When sunlight hits the PV cells, it causes electrons in the material to move, creating an electric current. This electricity can be used to power homes and businesses or stored in batteries for later use. Solar PV technology is renowned for its ability to generate clean, renewable energy, reducing reliance on fossil fuels and lowering carbon footprints.
Understanding Roof Orientation and Solar PV Efficiency
For optimal performance, solar PV systems should be installed on roofs that face true south in the Northern Hemisphere. This orientation allows the panels to capture the most sunlight throughout the day, especially during peak sun hours. A south-facing roof can harness the full potential of solar energy, leading to higher energy production and, consequently, greater savings on energy bills.
A northwest-facing roof will naturally receive less direct sunlight than a south-facing one, particularly in the morning when the sun is in the east. A northwest-facing roof can lead to a 30-40% reduction in solar PV efficiency compared to a south-facing roof. This can lead to a reduction in the amount of energy generated by the solar PV system. The panels’ efficiency on an NW-facing roof can be significantly lower, depending on factors such as the roof’s pitch, local shading, and geographic location. However, it’s important to note that solar technology has advanced, allowing for more panel orientation flexibility without sacrificing efficiency.
Is It Possible to Fit Solar PV on an NW-Facing Roof?
The short answer is that it is possible to have solar panels installed on a northwest facing roof, but the amount of energy (kWh) that you generate will be around 1/3rd of what you would generate facing south.
It’s also worth noting that it’s not only the roofs orientation that matters, but also roof tilt and the level of shading can impact on the production level too. Even minimal shading of 10% can reduce energy output by up to 50%.
The most optimal roof tilt will depend on the latitude of the location, but a pitch of 30 – 40 degrees should be sufficient to capture the maximum amount of sunlight as possible. A pitch between 30-40 degrees can help mitigate energy loss, with up to 10% improvement in output compared to flat roofs. In addition, the level of shading needs to be to a minimal as even just 10% shading can result in a 50% decline of energy output.
The time of year will also impact on your level of energy output from a NW facing roof. For instance, a north west facing roof will generate significantly less during the winter months when there is minimal light diffusion, whereas the difference in the summer is a much less due to the increased amount of light diffusion. Installing NW-facing roofs costs the same as south-facing roofs but may require additional equipment, increasing costs by around 10-15%.
Benefits of Installing Solar PV on an NW-Facing Roof
When considering the installation of solar PV on an NW-facing roof, it’s essential to weigh the potential return on investment (ROI). While a south-facing roof offers the highest efficiency and quickest payback period, an NW-facing roof may still provide financial benefits, albeit with a longer payback period. The installation cost, energy savings, and available government incentives should all be considered.
- Energy Savings: Even with reduced efficiency, an NW-facing solar PV system can still generate significant electricity, reducing your reliance on the grid and lowering energy bills.
- Initial Installation Costs: The cost of installing solar panels on an NW-facing roof is typically the same as on a south-facing one. However, additional equipment like microinverters or optimisers may be necessary to enhance performance, slightly increasing costs.
- Incentives and Tariffs: Depending on your location, you may be eligible for feed-in tariffs, grants, or other incentives that can improve the financial viability of your solar investment, even on an NW-facing roof.
Factors to Consider Before Installation
Roof Structure and Age
Before installing solar panels, it’s important to assess the condition of your roof. A roof that is nearing the end of its lifespan or in poor condition may not be suitable for a solar installation. If your roof needs to be replaced or repaired within the next few years, it’s often recommended that you complete that work before adding solar panels. Additionally, the roof’s structural integrity must support the weight of the panels and mounting hardware.
Local Climate
The climate in your region will also affect the efficiency of a solar PV system. Solar PV systems in the UK generally experience a 10-20% decrease in energy production during winter months due to reduced daylight. However, even in cloudy conditions, modern solar panels can generate electricity. An NW-facing roof may see a more consistent performance during the late afternoon and evening in the summer, which could be beneficial depending on your energy consumption patterns.
Read about the best season to install solar panels here.
Alternative Solutions
If you determine that a solar PV system on your NW-facing roof won’t meet your energy needs, alternative renewable energy solutions exist. For instance, ground-mounted solar panels can be positioned for optimal sunlight exposure, or you might explore wind or geothermal energy options. Another possibility is integrating solar with battery storage, allowing you to store excess energy generated during peak sunlight hours for use when your panels are less efficient.
Make an Informed Decision on Solar PV for Your NW-Facing Roof
Installing solar PV on an NW-facing roof has unique challenges, particularly regarding reduced efficiency and extended payback periods. However, thanks to advancements in solar technology like microinverters and power optimisers, you can still achieve a satisfactory level of energy generation, making this option viable for many homeowners and businesses.
While south-facing roofs offer optimal performance, NW-facing roofs can still provide significant benefits when equipped with the right solar technology. If you are committed to reducing your energy bills and carbon footprint, installing solar PV on an NW-facing roof can be a sound investment, especially with professional advice and installation.
Get Expert Guidance from EvoEnergy
To maximise your solar investment, working with a trusted and experienced provider is essential. EvoEnergy offers a comprehensive range of services, including solar panel installation, maintenance, and monitoring, tailored to meet your property’s unique needs. Our team of experts can assess your roof’s potential and recommend the best solutions to maximise your energy savings, even with an NW-facing roof.
If you’re a business owner considering solar panels, we invite you to explore the range of technologies and services available through EvoEnergy. Visit our Solar Panels for Business page to learn how we can help your business harness the power of solar energy, regardless of your roof’s orientation. Let EvoEnergy guide you through the process of achieving a more sustainable future!
Find out more about solar panel orientation today.