diff --git a/frontend/ui/device/basepowerd.lua b/frontend/ui/device/basepowerd.lua
index 34ca6c5f3..23da99647 100644
--- a/frontend/ui/device/basepowerd.lua
+++ b/frontend/ui/device/basepowerd.lua
@@ -21,7 +21,7 @@ function BasePowerD:init() end
 function BasePowerD:toggleFrontlight() end
 function BasePowerD:setIntensityHW() end
 function BasePowerD:setIntensitySW() end
-function BasePowerD:getCapacityHW() end
+function BasePowerD:getCapacityHW() return "0" end
 function BasePowerD:isChargingHW() end
 function BasePowerD:suspendHW() end
 function BasePowerD:wakeUpHW() end