Really do not have enough details but...
If you are sizing a 24 VDC power supply you need to know how much you will use. an example
If you have 10 vdc solenoids using 8 watts of power each then you would need atleast an 80 watt power supply.
Whenever I size a power supply I try to go 1.5 to 2 times larger than what I have calculated I need.