Achieving Maximum Generation

Harnessing Solar Power on Northerly Facing Roofs: Achieving Maximum Generation

Introducing Richard Fuell – Our Renowned Guest Blogger 

ChargeWorks is proud to have Richard Fuell, an industry expert with over a decade of experience in the solar industry, as our guest blogger. If you are remotely connected to an installer, chances are, you’ve heard of him. Richard has witnessed the transformative changes in the solar industry, adapting to advancements in technology and market developments. Previously associated with SolarEdge, a global leader in inverter manufacturing and smart energy, Richard now works with Aniron Renewables, a commercial EPC based in Northamptonshire. Today, Richard shares his insights on maximizing power generation on northerly-facing roofs.

My Quest for Maximum Power Generation

In recent years, I have consistently advised people to install as many solar panels as possible. The future will be all about generating as much power as you can, so do it right on day one. Solar panels perform well on clear, cloudless days when the sun shines brightly. However, when you consider the infamous British weather, clouds frequently dominate the sky, I firmly believe in generating as much solar power as we can, especially when it’s cloudy. It’s crucial to think beyond optimal sunny weather conditions and consider the entire year when planning a solar installation. In my opinion, filling the available roof space holds the key to unlocking the true potential of solar energy in the UK.

My Personal Experience: A Need for More Power

I moved house in late 2022, I knew I wanted to power my house from the sun but I could only physically install seven panels on the southerly-facing roof. These panels were only capable of generating approximately 2500kWh per year. I, however, craved a solar system that could produce much more power.

Therefore, I decided to install solar panels on both the southerly and northerly-facing roofs.

Embracing the Unconventional: Northerly-Facing Panels

Installing solar panels on a northerly-facing roof is not something typically recommended. However, I am always eager to explore new possibilities and maximize power generation within the available roof space. Admittedly, during the winter months, the northerly-facing panels receive no direct sunlight, resulting in very low power output. But as the sun climbs higher in the sky during early spring into summer, these panels receive direct sunlight and, more importantly, capture the late afternoon and evening sunshine. This afternoon and evening sunlight is superb because that’s when I use power more frequently in the house!  

Performance Analysis: South-East vs. North-West-Facing Panels

Analyzing the performance of both orientations throughout the complete year of 2023 proved fascinating. As you can see from the screenshot below, the seven panels facing southeast generated an average of 380kWh each, (with the ones closest to chimneys experiencing slight shading and reduced generation). As expected, the North West-facing panels produced less power compared to their South East counterparts, averaging approximately  220kWh per panel. However, considering they are installed on a roof typically deemed unfit for solar panels, their performance can indeed be considered commendable.

Surprising Consistency in Cloudy Weather

Throughout the year, I noticed some very surprising data. It did surprise me – on grey and cloudy days, the solar panels, regardless of their orientation, often generated a similar amount of power. This discovery raises the question of the economic viability of installing solar panels on northerly-facing aspects. However accurately calculating this involves considering installation costs, scaffolding expenses and comparing the performance with southerly-facing roofs. The self-consumption plays a vital role in this analysis, as northerly-facing panels generate power later in the day, coinciding with a decreased performance from southerly-facing panels as the earth rotates. Ultimately, the economics depend on the savings derived from reduced reliance on grid power and the potential financial rewards from supplying surplus power back to the grid. In addition, the timing of when the surplus power goes back to the grid.  It’s an absolute minefield to accurately calculate, I would even use the word impossible! However, I know it’s a great thing to do for various reasons.

Powering More Than Just the Home: Hot Water and Electric Vehicles

My intention was not only to generate solar power for electricity but also to utilize it for heating the hot water tank. To achieve this, I installed a smart hot water controller, directing excess solar power towards water heating. The result was astounding – my gas usage was reduced to zero for an impressive six months of the year. The system worked so effectively that I completely turned off the boiler in May, only reactivating it in October when the need for heating arose. Furthermore, during those six months, I was able to power my eight-year-old electric vehicle, equipped with a small 23kWh battery, using the surplus solar energy harvested in the afternoon.

Looking Ahead: A Bright Future for Northerly Facing Solar Panels

I firmly believe that the installation of solar panels on northerly-facing roofs will gain popularity, particularly in the commercial sector where the roof angles are often less steep compared to residential properties. The returns, financial benefits, and rewards from such installations depend on how efficiently we utilize the generated power, the total power consumption, and its timing.  The main message I still stick to is “install as much as you can.”


Installing solar panels is not solely about placing them on rooftops and reaping the benefits. It requires understanding power generation and strategically utilizing the generated energy. My personal experience demonstrates the immense potential of installing solar panels on northerly-facing roofs.  With the right technology and thoughtful utilization strategies, we can unlock remarkable solar power generation. As the world increasingly embraces renewable energy and the transition to electrifying the grid, exploring the possibilities offered by northern-facing aspects may hold the key to achieving unprecedented solar power generation.