To simplify solar efficiency further, we have divided all modules into 5 tiers based on their efficiency compared to all other solar panels. Now installers and consumers can easily communicate about module efficiency. Are the solar panels in the most efficient tier (Tier 1) or do they have average efficiency (Tier 3)? If modules are in the least efficient tier (Tier 5), let’s hope they’re cheaper than the modules in the above-average tier (Tier 2).
You no longer have to worry about the 4-digit efficiency value and wonder what it means. If a module’s efficiency is 16% or greater, then it is Tier 1. Only about the top 5% of all panels land in this range. Tier 2 panels are 15% efficient or greater and consist of about the top 20% of all panels. The least efficient modules are in Tier 5, meaning their module efficiency is less than 13%. As of Nov 1, 2012, there are more than 10,000 modules eligible for California solar incentives. These tiers allow you to sort them into easily understandable classes of most efficient, and least efficient. How efficient are your solar panels? “Below average, but I got a good deal on them.” “The most efficient, because my roof space is limited.” “My panels have average efficiency and my installer did a great job!”