Looks like I may not be able to get away without electrolytics this time. I need well north of 100uF and rated 200VDC or higher. The problem: Heat in conjunction with a required high MTBF. The cap(s) must live happily for at least a decade of continuous duty in an outdoors environment where the electronics often bake in the sun at 70-80C every day. Low ESR is also desirable and often that isn't even stated for higher voltage caps.
Not really feasible with ceramics. Film caps have fantastic ESR but they are very large. Cost is not such an objective this time. Within reason, meaning the capacitor or bank of caps can cost $10.
Does anyone know a top notch brand that has caps that offer well above the usual 105C/12000h?
I am also needing something similar for a 28V rail but that's easier.