Can bifacial solar panels still produce electricity at night?

No, bifacial solar panels cannot produce electricity at night. Like all conventional photovoltaic (PV) solar panels, bifacial panels rely on sunlight to generate electricity, and without sunlight, they do not produce power.

Why bifacial solar panels don’t work at night

• Dependence on sunlight: Bifacial solar panels generate electricity by converting solar radiation into electrical current using photovoltaic cells on both their front and rear sides. These cells require light photons to excite electrons, which only happens when there is sunlight or ambient daylight.
• No solar irradiation at night: At night, there is no sunlight or reflected light to activate the cells, so no electricity can be generated.
• No built-in energy storage: Unless paired with a battery storage system, solar panels cannot provide power when the sun isn’t shining.

What makes bifacial solar panels special during the day

• Bifacial panels capture sunlight from the front and also absorb reflected and diffused light on their rear side. This can increase electricity generation by around 5-30% compared to traditional single-sided panels.
• They perform better in conditions with less sunlight, such as cloudy days, early mornings, and late afternoons, which are common in the UK's often overcast climate.
• When installed over reflective surfaces like light-coloured rooftops, concrete, or snow, their rear side captures more reflected light, enhancing output.

Real-world UK context and applications

• In the UK, where direct sunlight hours are relatively fewer than in southern Europe, bifacial panels can improve the overall daily energy yield by capturing diffuse daylight in cloudy conditions that dominate much of the year.
• Recent UK government policies continue to support solar energy adoption through schemes like the Smart Export Guarantee (SEG), allowing small-scale generators such as homeowners and small businesses to sell surplus electricity back to the grid.
• Bifacial solar panels are increasingly used for commercial rooftops, solar farms, and urban installations in the UK because of their enhanced efficiency, particularly valuable in areas with limited rooftop space.

Practical advice for UK homeowners and small business owners

• Do not expect power generation at night: Install a battery system or remain connected to the electricity grid to ensure power availability after sunset.
• Maximise reflective surfaces: If possible, install bifacial panels over light-coloured or reflective surfaces to boost rear-side energy capture.
• Consider shading carefully: While bifacial panels tolerate diffuse light better, shading on either side can reduce performance significantly.
• Maintenance: Keep panels clean and free of debris to maximise light transmission on both sides.
• Sizing system with storage: Pair solar panels with a suitable battery system to store daytime energy for evening or night use.

Key pros and cons of bifacial solar panels for UK users

Pros	Cons
Up to 30% more energy from same area	No electricity generation at night
Better performance in cloudy, low light	Typically higher upfront cost
Longer lifespan due to double glass	Need reflective surfaces or optimal mounting for max benefit
Suitable for various mounting setups	Requires careful installation planning

Common mistakes to avoid

• Assuming bifacial panels produce power at night without storage or grid connection.
• Installing panels without considering the reflectivity of underlying surfaces.
• Neglecting proper cleaning and maintenance, leading to reduced efficiency.
• Underestimating initial investment costs and not factoring in long-term energy savings.

---

In summary, bifacial solar panels enhance daytime electricity generation by capturing light on both sides, which is particularly beneficial in the UK’s often cloudy environment. However, they still cannot produce electricity at night and must be combined with energy storage or grid connection for continuous power supply.