Theoretically, The life of power supply depends on the capacitance.
The life of capacitance is 2000 hours at present, which means it can keep running 2000 hours at 158 °F ( 75 °C ) , and the capacitance life will be extended one time per lowering 10 degrees and reduced one time per rising 10 degrees.
For example, if a power supply keeps working at 40 degrees, then the capacitance life will be extended 3.5 times; that is 7500 hours. In other words, if the power supply keeps working 24 hours one day, the life will be one year or so; if 8 hours one day, it will be about 3 years.
That is greatly oversimplified and so, usually far too inaccurate to rely upon. For example, while many capacitors are rated for 2000 hours, many more are rated higher still, especially solid polymer capacitors do not exhibit the halving of lifespan with each 10C temperature increase, or in smaller current PSU, also the ceramic, tantalum, and other non-electrolytic formulations tend to have a much greater temperature resistance than the old 10C/lifespan multiplier standard.
Further, that 2000 hours is typically specified on the capacitor datasheet at something like 100KHz ripple (a component of switching frequency and lesser so the powered load) and the temperature rating of the capacitor which is almost never 75C but rather 85C in general purpose capacitors or 105C in especially low ESR capacitors more suited for switching PSU circuits.
Further, ripple current is a function of total current capability. For example if you were to use a 2200uF, 16V capacitor, it would have a significantly lower lifespan in the same than the same make and model of capacitor rated for 22000uF, 25V, but in practice the designs are limited to the bare minimum in construction cost and space savings for consumer oriented equipment.
Dear friend, Thank you for your comments.