It depends on where you're at, but for a sunny place yes; somewhere like London a panel can harvest ~100 W/m^2 (0.5 MW for a football field with 100% panel coverage) averaged over the whole year, while in Arizona it's more like 230 W/m^2 (1.2 MW for a football field). NREL has some great insolation maps here: https://www.nrel.gov/gis/solar-resource-maps

For a permanent installation I would agree that solar would usually make more sense, but the mini reactor might be better in scenarios where it's replacing a diesel generator - emergencies, temporary events, confined spaces, etc.