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WaterPod rainwater calculations

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Revision as of 13:12, 8 October 2012 by Ers66 (Talk | Contributions) (Basic Calculation)

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The WaterPod will be collecting rainwater from a few of the impermeable roof areas. The calculations for collection are on this spreadsheet. There are three tabs feeding the results:

  • Tab:Collection Calcs - Calculates the monthly availability of the rainwater.
  • Tab:Collections Dimensions - Calculates the available rainwater collection area based upon the planned structures.
  • Tab:Regional Climate Data - Show monthly rainfall from historical averages. Could be made more current.

Regional Climate Data[edit]

The historical 1971 - 2000 Rainfall Normals for Central Park, New York[1] are:

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
3.42 3.27 4.08 4.2 4.42 3.67 4.35 4.01 3.89 3.56 4.47 3.91 47.25

Basic Calculation[edit]

 Collection\ Volume (gal) = Rainfall\ (in) \times \frac{1 ft}{12 in}\times Collection\ Area\ (ft^2) \times \frac{7.48 gal}{ft^3} \times Roof\ Coefficient \times Efficiency


 V=R \times A\times k \times e

(in some cases the efficiency of the system is assumed to be 100% and therefore equal to 1, having no effect on the rest of the equation.)

Click here for more detailed rainwater collection calculations and explanations.


Wait until the spreadsheet is finalized before posting the final conclusions here.