When upper-lower positional relationship on an optical path is defined such that the primary concentrating portion is at an upper position than the secondary concentrating portion, the secondary concentrating portion includes: a secondary lens provided above the power generating element; a lens supporting portion configured to support the secondary lens; and a shielding plate being a flat-plate-shaped member preventing sunlight to pass therethrough whereas allowing an upper portion of the secondary lens to be exposed from a hole formed in the flat-plate-shaped member, the shielding plate being fixed in a state of being mounted to the lens supporting portion, the shielding plate being configured to block light converging at a position outside the secondary lens.