For us the best way to make our coffee when camping off-grid is to use the generator. It is just too big a draw on the batteries to use a very high wattage Inverter.
Our style of OFF-ROAD camping requires us to be using the generator each morning to re-charge our battery bank using our on-board smart mode converter/charger setup. This is the time we make our coffee for the day... Our 2KW Honda Generator sits secured to the inside of the covered and lockable truck bed setting on the tailgate and is very quiet in operation. This has been our daily routine when camping off the power grid since 2009...
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We use the Cuisinart DGB-600BC GRIND AND BREW BEAN COFFEE MAKER which grinds fresh coffee beans and brews up into a thermos karafe. This only take around five minutes of time to give us a a good 10-cup source of brewed coffee.. We use the EIGHT O'CLOCK COLOMBIAN PEAKS brand of coffee (WALMART)
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Our backup coffee maker which does not require the use of the Generator is the Coleman peculator to be used on the propane stovetop and we grind the fresh coffee beans with a Mr Coffee bean grinder. Then we pour up the fresh coffee into a thermos karafe... This method of making coffee is not as good taste for us as the Cuisinart coffee maker gives us.
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The Mr Coffee grinder runs off of our 600WATT PSW Inverter we use for all of our Home Entertainment and other 120AC items we have for our low wattage daily use.This also takes around 5 minutes to make...
Another trick we do is to always use the same brand of bottled water to make our coffee with to get the same coffee taste we like.
Roy Ken