Epic’s latest UE5 addition promises a real boost for Lumen performance and could finally bring modern, dynamic lighting to lower-powered consoles like Nintendo Switch 2.

Epic has merged the Lumen Irradiance Cache into UE5’s main development branch. This probe-based, lightweight Lumen mode targets lower-end devices: compared to default hardware Lumen, it reduces occlusion detail and reflection quality, but dramatically cuts the performance cost—still far preferable to shipping with no Lumen at all.

Because Irradiance Cache is still early, it’s hard to pin down gains on low-power hardware. Even so, early signs are promising: a since-deleted GitHub commit—saved and shared on ResetEra—reports a 2.5× speed-up in the Lumen collection phase and roughly a 1.5× overall Lumen performance improvement per scene.

This lighter path could finally enable UE5’s signature lighting on constrained hardware, including Nintendo Switch 2, albeit with limits. Today, UE5 titles on Nintendo’s new console—such as Cronos: The New Dawn—ship without Lumen, likely because the CPU can’t sustain acceptable frame rates with such demanding features active.

It’s also telling that Fortnite doesn’t run with Lumen and Nanite on Switch 2, underscoring the extra engineering work required on the console branch of Unreal. With the new Lumen option now available, that groundwork appears to be underway. The hope: developers can leverage it soon and push Switch 2 ports’ visual fidelity closer to what we see on other consoles.

Source: WCCFTech, ResetEra