Product is rated for 22.8 years (365 days a year) when used 3 hours a day. That's about 25,000 hours. Interestingly, the warranty is only 3 years, which mathematically means the bulbs have to work 24/7/365 to reach the promised 25,000 hour lifespan. However, we then set up November 20, 2017. That was about 19 months ago. We run them a lot more than 3 hours a day. Let's say we use them 15 hours a day (which is slightly more than the actual amount, so a conservative usage estimate) for 19 monthsβ¦