Is there anything I can use to replace an mechanical automotive relay to reduce the size of my project enclosure. I'd like the substitute to have the same ratings as a typical mechanical relay, 12 volt to activate, can withstand up to 30amps.
There are plenty of MOSFET components which can handle 30 amps, but you'll need to look for one with a low rds-on to keep the heat low with 30 amps of current flowing. You will probably also need to add a 30 amp diode if your load is at all inductive.