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One-day real-life MPG and costs with my one-month-old Prius
May 13, 2006 (From the CalCars-News archive)
This posting originally appeared at CalCars-News, our newsletter of breaking CalCars and plug-in hybrid news. View the original posting here.
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We'll have an update on our fundraising efforts for our trip to DC later today--we're getting close, helped by the 100% match offer. If you haven't contributed yet, go to­phevtodc.html (we'll also be updating the map. Meanwhile, here's a report I prepared for a reporter, followed by an editorial for Americans for Energy Independence that covers some of the same ground. We emphasize that PHEVs offer "the environmental features" of lower gasoline use and lower CO2 emissions; here are the economics from which you can figure out the payback to the individual driver. (Of course, each person's driving patterns and fuel costs vary.)

May 11 report: 51 miles, mostly on highways at 50-65 mph, driving about 4 miles uphill to I-280 for 10 miles, back at congested highways speeds on US-101, and later in the day another 20 miles on US101.

A half mile from home this afternoon, my batteries were depleted. I drove 50.8 miles in full or partial-electric mode, averaging 124.1 MPG plus 123 watt-hours/mile of electricity. Here's the math, assuming $3 gasoline and the national average electric rate of 8.5 cents/kiloWatt hour. (Off-peak can be 5 cents, Texas windpower and Washington hydropower could be 2 cents):

Gasoline: 50.8/124.1 = 0.40935 gallons = $1.23 Electricity: 50.8 X 0.123= 6.24 kwh = $0.53 TOTAL = $1.76

What would that same 50.8 miles have cost in other cars?

In my old (unconverted) 48 MPG Prius, 1.0583 gallons = $3.175

In a 25 MPG non-hybrid, 2.032 gallons = $6.10

That's the dollars. As for the petroleum displacement, note that I used 39% of the gas I'd have used in a hybrid and 20% of the gas I'd have used in a standard passenger car.­current_editorial.asp Our guest editorial at Americans for Energy Independence (co-sponsor of our BETTAH animation) A Real Life 100+ MPG Car May 12, 2006

I've just finished a full afternoon running errands around the San Francisco Bay Area. It was a mostly ordinary day: I drove 42.9 miles, putting me right in-line with the 75% of Americans who drive 40 miles or less daily (50% drive less than 25). I spent about half my time on the highway, the other half making short trips in town. And I did it all in my 2004 Toyota Prius, like a good percentage of my fellow Bay Area drivers.

Oh, and one more thing: I got 137.8 miles per gallon.

I drive a plug-in hybrid (PHEV). A PHEV is much like a regular gas-electric hybrid, only with larger batteries and the ability to recharge from a household outlet. My car, one of only ten plug-in Priuses in the world, fills up from an extension cord every night in my garage.

I don't have to plug it in. If I don't my car behaves just like a standard hybrid, using its gas engine and regenerative braking to constantly recharge the battery. But why wouldn't I plug in? In nine seconds (that's the amount of time it takes me to connect the extension cord to my bumper each night) I can fuel my driving with cleaner, domestic electricity. In nine seconds I get 30 miles of all-electric range every day. In nine seconds I save more than $2 a gallon:

The average national electricity rate is 8.5 cents/kilowatt-hour. My plug-in Prius' capacity of 9kWhr gives me 30 miles of all-electric range. That's 30 miles for $0.77. If you compare this to the standard vehicle average of 25MPG, a plug-in fills up with electricity for 64 cents a gallon. Compared even to a standard Prius' 48MPG it costs just $1.23 a gallon. I haven't factored in that some areas of the country have off-peak (overnight) rates as low as 4-5 cents per kilowatt-hour, so if you live in one of these areas, I'll leave that math to you.

I like and promote plug-in hybrids not just for the economic gains. PHEVs also tackle:

1. Global warming: Over 12,000 annual miles, here's the average vehicle CO2 output: (note that the PHEV numbers are "well-to-wheel," meaning CO2 from electrical generation is included)

Standard car: 12,000 pounds CO2
Stock Prius: 6,000 pounds CO2
PHEV Prius: 2,000 pounds CO2

These numbers are based on the California grid. Nationally, despite the electric grid being half-coal, the PHEV number is 3,900 pounds, but will only improve as the grid gets cleaner.

2. Jobs: Car makers can make money selling better cars. After-market companies can convert existing hybrids. Also, communities that are so polluted they can't attract (or aren't allowed to build facilities for new businesses) can start reducing dangerous emissions.

3. Oil dependency: I can't remember the last time I visited a gas station. Over my 42.9 miles today (in which I burned less than a third of a gallon of gas), I used 18% of the gasoline of a normal car and 34% of a stock Prius.

As pointed out in last month's editorial by Professor Kammen and in the UC Berkeley study, Towards Energy Independence by 2025, plug-in hybrids are a gateway technology to an oil-independent America. You may ask - where does ethanol fit in? Even plug-in hybrids need a fuel source for extended range driving and ethanol can play an important part in reducing our gasoline consumption even further. But is America capable of producing 140 billion gallons of ethanol a year-the amount of gasoline our cars currently use? The short answer is "no." A study released last year by the Department of Energy and Department of Agriculture stated that a 30% replacement with ethanol would be doable, but a considerable challenge. But we may never need to hit the 30% mark...

Plug-in hybrids are ready today. The technology is here. The batteries are ready. Our domestic power grid can accommodate off-peak charging for tens of millions of PHEVs. And when combined with biofuels, plug-in hybrids can achieve 500MPG of gasoline, effectively eliminating our need for foreign oil. By using ethanol primarily as the "range-extension" fuel (when you need to drive beyond the typical 30-40 miles a day), we can cut our gasoline production needs by 70%. Meanwhile, the electric grid keeps on getting cleaner and cleaner, and we approach completely carbon-free transportation.

Converting my Prius cost $12,000; it was done after-market, by hand, without the benefits of mass production. Current figures estimate that production PHEVs would cost just $2,000-3,000 more than a conventional hybrid. With government and other incentives they could cost even less. What's left? An automaker to fire up the production lines for this "car of the future"-today.

To see a short, humorous animation on the value of plug-in hybrids, visit By signing the Petition at the end of the animation, your voice will be added to the thousands who support our pursuing a "bettah way" - starting today.

Felix Kramer is the founder of the California Cars Initiative (, a non-profit group of entrepreneurs, engineers, environmentalists and citizens promoting plug-in hybrid cars.

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