[Vwdiesel] Was-It's peak oil,duh,-now-mileage comparison

[William J Toensing]

I believe the attraction of diesel, to me anyway, is to save money. Currently, here in Grass Valley, CA., 87 octane gas is selling for $3.499 a gallon & diesel for $4.099 a gallon, a spread of .60 cents a gallon. I think it boils down to the cost per mile for fuel, not MPG. Why diesel is now costing so much more than regular, I don't know. Probably because Big Oil can get it. Whether this much spread between regular gas & diesel will continue, I don't know. I currently drive a 2001 Ford Focus ZX3 5 speed. It averages around 28 MPG. What I would really like to get, if I can afford it, is a new TDI  Jetta sportwagon. I am also considering a Toyota Prius. I suspect the VW will handle much nicer, but will be more costly to maintain in view of VW's less than stellar reliability record. In Calif., the Prius has a 8 year 150,000 mile warranty on all the hybrid components including the batteries. 
Based on the current cost of regular & diesel, assuming an average of 45 MPG for both the Prius & the TDI sportwagon I came up with the following cost per mile: 2001 Focus $0.125, TDI $0.091, Prius $0.077. The projected fuel cost for 100,000 miles would then be: Focus $12,500, TDI $9,111, Prius $7,777. Additional fuel costs for the next 100,000 miles would be, using the Prius as the benchmark, would be: $4723 for the Focus, $1,334 for the VW TDI. Since my Focus is now 7 years old & has 108,000 miles on it, deprecation will be minimal but I would anticipate considerable repairs for the next 100,000 miles whereas the Prius would have minimal repair costs. VW-TDI, who knows but probably much less than my Focus would require. Deprecation on the Focus would be less than on the TDI & Prius since the Focus is probably now worth about $4,000.
GM plans to bring out the plug in Chevy Volt in the fall of 2010 as a 2011 model & I hear Toyota will bring out a plug in Prius at that time as well. The advantage of a plug in vehicle will be that they can run on batteries along for the first 40 miles before the engine kicks in to recharge the batteries. Since 80% of drivers drive less than 40 miles a day, 80% of the time, a plug in hybrid would make the most sense to me, in terms of saving on fuel costs. I fear we will be paying $5 or $6 a gallon for gas & diesel in a few years.
If you think my projections are wrong, please pick them apart. I am currently retired & will reach age 75 this coming May. Cost wise, I think it will be much cheaper to keep my Focus & get my '81 Dasher diesel wagon up & running, than to get a new car, at least until the plug in hybrids become available.