Real cost for SWG use

[PatL34]

I did do a check of the running costs a few years back, but did not keep a record of the calculation, so here goes for another try.

Monthly Electric Cost
--------------------
240 volt 2 phase supply at 1.0 amp = 240 watts. This is the value of the supply to the transformer in the DG220 Control Unit only.

So 240 X 12 hours/day = 2880 watthours X 365/12/1000 = 87600 watthours = 8.76Kwh per month X $0.1/Kwh (per OUC rates rounded) = $8.76/month

Monthly Cell Wear Cost
----------------------
Assume $550 replacement cost, 5 year life, 12 hours/day for 365 days.

550/5 years/12 months/2(1/2 day) = $4.6

Monthly Muriatic Acid Cost
-------------------------
2 gallons @ $3.67 = $7.34

Total Monthly Cost = 8.76 + 4.6 + 7.34 = $20.7

(Corrected values applied in this post)

Any upsets and extra chemicals like baking soda, Borax, and incidental bleach are not included.

Hope this helps, and if there any questions, please let me know.

Pat

[KurtV]

Pat,
Thanks for the info. One minor quibble; the average residential electricty cost in the U.S. in 2003 was 8+ cents per kilowatt hour.

http://www.eia.doe.gov/cneaf/electri.../table5_3.html

[Brock]

Yup, actually I would bet it is closer to $.10 now. On the other hand did you actually take a reading off the power supply for the unit or was that just what it was rated for? 24w does seem reasonable for what it is doing though.

At 8.76 kw per month at $.10 is still $.876 a month so you have the cost correct, maybe slipped a decimal?

[PatL34]

I went and did a further measurement to check my original figures, and did in fact read my amp meter incorrectly.

The electric cost should be 1 X 240 = 240 watts x 12 hours daily running time = 2880 watthours X 365/12/1000 = 8.760Kwh X $0.1/Kwh = $8.76

Total cost = 8.76 + 4.6 + 7.5 = $20.86

This seems to compare with what I calculated previously 2 years ago.

Sorry about the error.

Pat