Expect to pay less than $200 for a 100-watt flexible solar panel. The price you pay will vary depending on the panel's efficiency, capacity, brand and durability. Application Value: While flexible panels cost 50-100% more per watt than rigid panels, their unique installation capabilities and weight savings make them the only viable solution for curved surfaces, weight-sensitive applications, and portable power needs. Note: Prices may vary based on quality, warranty period, country of manufacture, and whether the panel includes. Rigid solar panels can convert up to 23 per cent of sunlight into electricity, while most flexible models range from 10 to 18 per cent. 1 inches thick and easily mountable – a perfect option for portable solar generation on boats or recreational vehicles. US PV solar system pricing by.