SternWake said:
And here are those details.
{snip}
Because guessing sucks.
Score!
Man those are the details alright! I knew we'd get you going SW!
I wanna buy you (at least) a beer for all the research you do...
Those are excellent numbers, very impressive. I'm learning, from your
experience, and from Sabs
experimenting.
It's a win-win situation for anyone reading all of this...but, those are all raw numbers, even though they
look like the final data.
A 1.8 cf fridge is not the same as a 4.3 cf fridge or whatever the numbers are.
Keeping perishable food cold is a 'job' we assign to a fridge. That's the
only reason we buy one, not for looks, not for something to enjoy. It only has to do one thing: Keep a certain amount of food cold.
So, working with a single fridge in each rig:
Take all of the raw data, then figure in the POUNDS or cubic feet of food kept cold, divided into the total number of dollars spent on hardware....THIS is the final, useful number.
You could even throw in one more number: The amount of food (in dollar value) kept under safe temperature control, versus the number of dollars spent to keep them there.
Let's say you had $100 worth of food in yours, and you have spent lets say, $1500 on
the fridge, the fans, the panels, the charge controllers, the batteries, and misc items to make it all work.
Then we have ol' Sab keeping $230 worth of food safe and cold, (since his will hold about 2.3 times more food in volume, assuming the products are all about the same individual prices). Wife is happy, lots of food, enough food for 2, for 2 weeks on solar alone. (or a month for one person) Sure, it's sucking lots more of that precious solar juice. Lets say he also spent $1500 on the fridge, inverter, charge controller, batteries, misc items, and the panels.
(Plus he will save some gasoline with fewer trips to the grocery store. But lets keep it simple and ignore that part.)
So he spent the same $1500 to get a 'bigger' job done....
NOW which is more efficient?
It's a bit like comparing the fuel mileage of my Ford cargo van, fairly efficient, at lets say, 18 mpg avg, compared with the fuel mileage of a modern aerodynamic Class 8 tractor-trailer getting 8 mpg, average.
Sure, these raw numbers don't favor the truck....but the truck is moving the driver and 45,000 pounds of temperature controlled groceries down the road, while my van is able to haul a driver and lets say, 2000 pounds of groceries at the most.
When you do the math: For a 500 mile day trip, the truck will burn about $156 in diesel, at about $2.50 per gallon.
For 500 miles in my van, I will burn about $61 in gasoline, at $2.20 per gallon.
Dividing the cargo weights by the dollars spent, we moved the cargo for 288 pounds per dollar spent (on fuel) with the semi. But each dollar in gasoline pumped into the van only moved about 32 pounds of cargo. It would take 9 vans to move the same amount of cargo, for a total fuel cost of $549!
So it just depends on the 'work' you are trying to do.
Or so it seems to me.
Your thoughts please?
