I don't know the power budget for the satellite, but we can make an educated guess : the occulter is 1.4 meter diameter, or a surface area of 1.54 square meter. That's an upper bound for the surface area of the solar panels - there's nothing sticking out beyond the disk, that would interfere with observations.

Solar power at earth is about 1.3kW/sqm, solar panels are maybe 20% to 30% efficient. That puts you in the ballpark of 400 to 600W.

150W on standby would be a pretty big bite out of your power budget.