[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: (ET) ET and actual fuel costs

Good job with the math. Nice to know there's a operational financial advantage, although in my case, I will have somewhat more invested in my 30-year-old ET than in a typical shiny new ICE. For me it ends up being as much a lifestyle choice as anything. Over time I'll end up spending any energy savings in replacement parts & restorative work.
I wonder how long an E20 motor would typically last, & how much to rebuild? My John Deere 170 motor looks & runs like new (no oil use) but is 17 years old (and currently for sale!). I'd guess it would go another 17 given similar use & care. 


On Sep 7, 2005, at 7:56 PM, steves wrote:
Just thinking it over (no calculators or spreadsheets involved) I'm guessing that the ET and the ICE would at least come out to be a wash, 



 -- Actually NO! - see below
plus you'd have the added benefit of less noise, no fumes, and reduction in air pollution. 
Anybody want to run the numbers?  :^)
I have over 2 acres of rough terrain, but mostly flat lawn. My old Craftsman tractor with a pooged 20 hp gas engine needs about 3 gallons (@$3.29 this week) = $10 to mow it.
Very heavy mowing this week, but I used my (under restoration) C185 (E15) with front deck. Half on Saturday, half Sunday. Recharge power was 6.17 kw and 5.2 kw = 11.37kw = $1.14 at my electric rates. 

--------------------------------------------------

A quick shot:

Using the numbers above and assume:

1. 20 mows per year
2. $15 for oil/filter/plug
3. Battery cost = $420 (6*$70)
4. Battery life of 7 years
5. I'll be conservative and hope gas settles back to $2.50/gal
6. I'll be conservative and say $0.20 /kwh


On a yearly basis:

ICE:
 Gas cost = $2.50 * 3 * 20 = $150
 Oil/filter/plugs          = $ 15
 Total ===================== $165

ET:
  Electric cost = $.20 * 11.37 * 20 = $ 45
  Battery cost  =  $420/7           = $ 60
  Total ============================= $105
That's a significant difference. And I used pretty conservative numbers. Also consider that ICE's wear out and few people rebuild them, where the only real wear item on the ET is the batteries, and I've accounted for that. This also ignores time spent doing yardwork, gradening, and snow removal. 

- SteveS





_______________________________________________
Elec-trak mailing list
Elec-trak cosmos phy tufts edu
https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak