PV Gap

Marie Said:

Can someone please help me? I don't get this math problem at all?

We Answered:

I like the units on the surface area.
Anyway,

What you should do (#1) is find the area of a single cell, and then multiply that by the amount of cells. That will get you a total area:

(1.25*2.75)*65,000 = 223,437.5 square inches

To get square feet, divide by (12 in/ft)^2, or 144
1,551.64931 square feet


To do the second problem, let's say there is a unit of energy called Wicks (there isn't, by the way). 1 wick is defined to be the amount of energy that a 1% efficient 1.25 by 2.75 cell can produce.

If the cells run on 18% efficiency, then there are 18 wicks per cell, and there are 65,000 cells, so 18*65,000 = 1,170,000 wicks. If they instead were 12% efficient, there would be 12 wicks per cell, and we want to produce 1,170,000 wicks. So there would be 1,170,000/65,000 = 97,500 cells.

How much surface area do 97,500 cells take up? Well, using the procedure from before:
1.25*2.75*97500 = 335,156.25

335,156.25/144 = 2,327.47396 square feet

How much more is that than the original 1,551.64931?

2,327.47396 - 1,551.64931 = 775.82465 more square feet of surface area.