How do modern inverter generators achieve greater fuel economy compared to traditional open-frame models?

Answer

By running the engine at variable speeds based on the load after initial DC power generation

Inverter generators first generate DC power, clean it electronically, and then create AC output, which allows the engine to run at variable speeds based on the load, leading to significant gains in fuel economy.

How do modern inverter generators achieve greater fuel economy compared to traditional open-frame models?
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