Solid-state microwave generators have been developed to replace magnetrons recently, and they can run at variable power. http://electronicdesign.com/blog/say-g

Solid-state microwave generators have been developed to replace magnetrons recently, and they can run at variable power. http://electronicdesign.com/blog/say-good-bye-last-vacuum-tube-product http://electronicdesign.com/blog/say-good-bye-last-vacuum-tu... Using the MHT1003N, manufacturers can use from one to eight of these 250 W units to build a microwave oven with the desired power level. And the magnetron’s 4 kV power supply goes away in place of a supply of 28 to 50 volts. Furthermore, the crude on-off control of the magnetron can be replaced with full variable power control. However, as far as I know there's no consumer devices containing things like this yet - the only ones I've seen were concept devices from Freescale. This article suggests we won't see them until 2017, and then only in high-end cookers: http://www.electronicsweekly.com/news/design/the-future-of-microwave-cooking-is-solid-state-2016-01/ http://www.electronicsweekly.com/news/design/the-future-of-m...