Q&A with the Solar Team is a new article series featuring Energy Trust’s take on common questions from customers. Have a question you’d like to know our take on? Send it to the Solar team and it could be included in the next issue of Insider.

Q: Which solar panels are the most efficient?

A: This is probably the most common question we hear about solar technology. Practically speaking, the answer to this question isn’t useful for a customer because solar panel efficiency is not the metric you use to choose solar panels for your home. The customer is actually asking which panels are the best value for their money.

Energy Trust advises customers to focus on the levelized cost (cost per kilowatt hour over the life of the system) instead of the absolute efficiency of any given product. Many customers and trade allies are surprised to learn that higher-performance modules are often a better value than lower-performance, lower-priced equipment. Customers should also consider other features that impact long-term value, such as warrantees.

Under some circumstances, a customer needs to maximize production from a limited area. In these cases, efficiency really does matter and price is less of a determinate.

If your customer remains steadfastly interested in solar cell and panel efficiency, point them to a reliable resource, such as “Which solar panels are most efficient?” by Zachary Shahan of Clean Technica or National Renewable Energy Laboratory’s Best Research-Cell Efficiencies chart, updated annually.