How do you improve a microwaves efficiency?

[MR GUS]

The technology (mainstream) is at least 30 yrs old now, so what improvements could be made to reduce energy consumption other than more / better insulation.

..does anybody super-insulate a cupboard set microwave oven (with grill / oven facility) if so what difference to warm up / down times does it make?
do they have any insulation as standard? is this what generally makes them "E" energy rated?
 Any improvements on the horizon?

[dhaslam]

Microwaves  heat from the centre of the food and insulation wouldn't make any difference.   There are more concerns about destruction of  vitamins etc in food.  Not sure if this can be corrected.

http://www.relfe.com/microwave.html

[Richard Owen]

I think that's the biggest load of tripe I've read in ages.

Typical mashed potatoes scaremongering. Full of all the warning signs: no research, concerned maverick scientists, gagging orders, unsubstantiated claims, etc. etc. etc.

Microwaves don't cook from the inside out. They cook to a depth of about 1". When subjected to microwave energy, water molecules rotate rapidly around one oxygen atom. The rotational energy causes heating.

Google for nutrients and microwave cooking. There is a lot of research that microwave cooking retains more nutrients than conventional cooking.

A microwave oven is a Faraday cage. That's why the door has a metal grid across it. Electromagnetic energy stays inside the cage.

That's it.

Unless of course, it's another example of a global conspiracy.

[MR GUS]

..I understand the faraday cage (we used to have one) ..when I referred to improvements it was due to the fact that the majority of microwave ovens are now microwave COMBINATION ovens consisting of micro power,  bake oven & grill, now with the two additional aspects (again available since the 80's in this triple form) then should they be more heat retentive? / modern design savvy so they don't leak heat through panels & have to compensate with more power useage, ..how efficient could a modern microwave be by comparison?

[heatherw]

Microwaves need plenty of ventilation and cooling or they blow up.  I've seen this several times in bespoke kitchen cupboards where insufficient space was left around the oven for air to circulate.

Edit - well let's not exaggerate.  'Blow up', loosely used, I mean autodestruct or burn out electrical circuits with smoke coming out etc.

[MR GUS]

which would be pretty easy to change if the need arose!