That's kind of odd wording for saying that Parker is heavily protected against the intense heat and radiation environment so close to the sun.

The spacecraft has a sun-facing shield made of two panels of superheated carbon-carbon composite sandwiching a lightweight 4.5-inch-thick carbon foam core. The Sun-facing side of the heat shield is also sprayed with a specially formulated white coating to reflect as much of the Sun’s energy away from the spacecraft as possible. All of the spacecraft systems are behind the central part of the shield, where they are kept below 30°C. Unshielded, the spacecraft's systems would fail in tens of seconds.

Power comes from two solar arrays, the larger main array retracts behind the shield during approache closer than 0.25 au, and the smaller array is liquid cooled.