Efficent microwave?
- Thread starter squarpeg
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Brucey
Solar Wizard
There are some more expensive true inverter style that will ramp down power versus on/off cycling as the traditionals ones run.
ScropusGobbleBottom
Corn Pop was a bad dude.
An inverter style microwave can heat food more gently. but for longer
I have an inverter microwave and it draws 2000 watts on high/default.
I love dialing back to 30% for soups. (no eruptions)
Its wonderful for defrosting.
You can soften butter and ice cream nicely without any melting! That is awesome!!
I am no expert and I dont know why your microwave is drawing 1200 watts when it should be 700.
I have an inverter microwave and it draws 2000 watts on high/default.
I love dialing back to 30% for soups. (no eruptions)
Its wonderful for defrosting.
You can soften butter and ice cream nicely without any melting! That is awesome!!
I am no expert and I dont know why your microwave is drawing 1200 watts when it should be 700.
Last edited:
hwy17
Anti-Solar Enthusiast
You may be observing a reading that is actually kVA and not Watts. I notice that my 1000W microwave reads more like 1200+ on my XW inverter display, but I think that display is actually reading kVA.
fratermus
Solar Enthusiast
- Joined
- Mar 19, 2021
- Messages
- 529
My understanding is the 700w number is cooking power emanating from the magnetron. The 1200w is what it takes to do that.
hwy17
Anti-Solar Enthusiast
Wikipedia says 50-65% efficiency for microwaves, in converting AC power into microwave energy. So that lines up well.
There's probably significant power factor in play. Most microwaves have a serious transformer and/or other electronics that kick the pf waayyy off of 1.0. That'll mess up a power reading taken with a device that doesn't understand that and calculate accordingly.
Zwy
Emperor Of Solar
Inverter type or turn down the settings.
Brucey
Solar Wizard
Zwy
Emperor Of Solar
Yes, I think that is correct, we had the discussion in a thread a year or so ago and the microwave I had in my camper would cycle the amp draw. But it does help with a slightly undersized system.
The convection microwave I just installed in my camper draws 1500W when heating a cup of water using the beverage setting. I didn't check the convection part (heating element) as I figured it might melt the 2/0 battery cables.
Seriously, I think the element is 1700W.
Not a concern overloading the inverter, I don't think turning settings down or cycling changes the efficiency. Just surprised by how inefficient it is. I assumed wrongly so that something labeled 700 watts drew 700 watts. Not the case on any I guess.
Brucey
Solar Wizard
I think for optimum efficiency you need an induction cooktop very little wasted energy
grizzzman
Photon Vampire
- Joined
- Sep 21, 2019
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- 2,856
I fell into the same trap. Ad said 700 watts and pulls over 1100 watts. Luckily my 12/1200 will run it even with the Starlink and entertainment center running, but to be honest it's just starting to get hot here so......
sunshine_eggo
Happy Breffast!
I have found with great consistency that microwaves, standard and inverter, draw 1.6X their rated output power.
The nice thing about inverter microwaves is that they actually operate at a reduced power rather than operating at 100% power for reduced time on a standard microwave.
The nice thing about inverter microwaves is that they actually operate at a reduced power rather than operating at 100% power for reduced time on a standard microwave.
Cronix
New Member
Is that on a 20a breaker? Seems that would very easily trip a regular 15a.
The bad thing about inverter M/W's is they are not cheap. My standard 1000w M/W only cost me $95 brand new. Yes it pulls 1600w when operating. This is not a problem for my 3kW AIO except if I forget that I am using 2000w to heat the hot water tank up at the same time. Why manufacturers do not rate M/W for total running wattage I do not know. But a lot of small kitchen appliances are hard to find actual running wattage. Best to be available to supply a minimum of 15a (20a even better) for any standard plug in item.
ScropusGobbleBottom
Corn Pop was a bad dude.
Yes on a 20 amp breaker
sunshine_eggo
Happy Breffast!
They used to be a little more reasonable. I bought a panasonic 1200W for $160, and it was worth the premium. You can find Toshiba and Emerson for $130-160, but the Panasonic seem to all be over $200. Hmmm... costco does have it for $189... still.
Pretty much everything is rated on output. A 1 hp pump provides 1 hp of pumping power even though it may consume 1.25-1.5 hp of electrical power. The only way to be relatively certain is to check the data plate for current requirement.
dopeassjackson
New Member
My $50 700w microwave also does about 1100w. If I would have known that I would have cought bought a normal wattage one.
My generator is remote start and on a transfer switch so at the push of a button I have full generator power. 10 min of generator run time a day isnt the end of the world.
OzSolar
Whatever you did, that's what you planned.
I don't see that it's already been mentioned but this is where understanding power vs energy is important.
Watts vs. Watt hours
My gut tells me that For most people, the daily difference in Watt hour usage of the most efficient microwave vs. the least efficient is going to be hard to even measure.
Watts vs. Watt hours
My gut tells me that For most people, the daily difference in Watt hour usage of the most efficient microwave vs. the least efficient is going to be hard to even measure.
ksmithaz1
Solar / EV Junkie
Something about the 18K umm PV comes to mind. A 500 Watt PC power supply will draw more than 500 watts if it is actually outputting 500 watts. Depends on the reference perspective and marketing. A vacuum cleaner with a 10A motor often doesn't have a motor that actually draws 10A. In the case of a microwave the perspective is from the point of view of the food you are cooking, same as a PC power supply is from the point of view of the power supplied to the system, because that is what you need to know. A 500W input power supply does not tell you anything useful, nor would a microwave that uses 1000w necessarily tell you how fast it will cook your food, compared to another 1000w unit. You want to know output not input.
DPC
Solar Enthusiast
A microwave is not very efficient.
But they heat the food not the air.
But they heat the food not the air.
ksmithaz1
Solar / EV Junkie
Oh c'mon. I use my microwave every night, it runs for at least 10 minutes a day on average. So for a 1500 watt draw we are talking 249 watt/hours per day, 7.5KWH per month. Thats going to really make a significant impact on my electric bill and/or solar storage if I can shave it down to 200 wh/day. Save me at least $0.25/mo!
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