overall efficiency; combined efficiency
Technical term used in engineering and industry to describe the total effectiveness of a system, combining multiple efficiency factors. The specific 'lamp and auxiliary efficacy' meaning is an industry-specific usage.
The overall efficiency of this system reaches 85%.
When calculating the combined efficiency of a lighting fixture, both the lamp and the ballast are taken into account.
効率 is general 'efficiency'; 総合効率 specifically refers to the combined or overall efficiency of a system.
Compound of 総合 (そうごう, 'comprehensive, overall') and 効率 (こうりつ, 'efficiency').