Best Solar Panels of 2025Panasonic: Best OverallREC Group: Best For Harsh ClimatesQcells: Most PopularCanadian Solar: Most PowerfulMaxeon (by SunPower): Best Warranties.
What is the most important criterion when choosing a solar panel?
Many people consider efficiency to be the most important criterion when selecting a solar panel but what matters more is the quality and support as explained earlier. Quality is generally related to real-world performance, reliability, company history and manufacturers warranty conditions.
The quality of the installation and other equipment (such as the inverter) also contribute to how good the solar panel system is overall. Price also varies depending on the solar panel brand and installer. The Which? members we surveyed owned solar PV panels from more than 20 different brands.
Sunpower panels are popular and considered the most trusted brand in North America. See the detailed SunPower solar panels review. REC produces high-quality, reliable panels, which are a very popular high-end choice among solar installers, notably the Alpha Pure series.
How do I choose a solar panel brand in the UK?
Product availability in the UK can also determine which brands installers are able to fit. When you talk to different installers (we'd recommend getting three quotes), use our research on solar panel brands to help you choose between them. Read our full buying advice for solar panels.
For example, solar panels with the highest power ratings are ideal for large households, while more efficient panels are a better choice for small roofs and homes that don't get much sunlight. We'll offer more guidance on choosing the best solar panels for you in our buyers' guide, below.
What is the efficiency of a solar panel?
The efficiency of a solar panel is a measure of the amount of solar irradiation or solar energy which falls on a specific area and is converted into electricity. The term efficiency is thrown around a lot but a slightly more efficient panel does not always equate to a better quality panel.