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Modified Prius gets up to 180 Miles Per Gallon
shupp writes "The NY Times (free reg. required) reports in that some folks are not content with the no-plug-in rule that both Honda and Toyota endorse. By modifying a Prius so that it can be plugged in, Ron Gremban of CalCars states 'I've gotten anywhere from 65 to over 100 miles per gallon'. The article also reports that 'EnergyCS, a small company that has collaborated with CalCars, has modified another Prius with more sophisticated batteries; they claim their Prius gets up to 180 mpg, and can travel more than 30 miles on battery power.'"
In TFA, it said the price of adding plug-in tech was $3,000 to a hybrid vehicle. However, to recoup that $3,000 would require you to save about 1,300 gallons of gas (at 2.25/gal). If you were getting 50MPG, and bumped it up to 100MPG, you'd have to drive at least 130,000 miles to recoup it - and that doesnt even count the fact that you'd be spending money on electricity, that would only increase the amount of miles driven.
It can help in other ways, perhaps the power plant where you are getting the electricity from is cleaner burning (or nuclear) than your car, and it reduces overall air pollution.
The Doormat
If you're not outraged, then you're not paying attention.
Still, it's a claim to be approached cautiously. Perhaps improved batteries can improve hybrid milage -- but by a factor of 3? In any case, the "up to" is a hint that this is one of those meaningless "gee whiz" statistics, as with "The IQ of Slashdot users is as high as 300."
Well, googling got me this:
"The energy content of a gallon of gasoline ranges from about 109,000 to 125,000 Btu. The average is about 114,000 Btu."
and this:
"1 kW = 3413 BTUs"
so, one gallon of gas (on average) = about 33kW
Electricity ranges from about 5 - 10 cents per kW, so a gallon of gas (more than $2) has as much energy as $1.65 - $3.30 of electricity.
I urge all readers of these lively threads to view our Fact Sheet, found at http://www.priusplus.org/ -- paying special attention to the fact that our MPG results must be combined with the electricity used.
Also look at the new section at our vehicles page where we document the benefits of PHEVs even when they're recharged from a dirty (coal-fueled) grid.
We've added a link to this discussion at http://www.calcars.org/kudos.html
Felix Kramer, Founder, CalCars
Founder, California Cars Initiative and PRIUS+ Campaign
Replace all instances of kW with kWh. kW are power (1 horsepower ~= .75 kW). kWh are units of energy (1 kWh = 3600 kJ ~= 3412 BTU).
Um, no. The Chernobyl people had turned off most of the safety equipment in order to conduct a test. The reactor was almost at zero power. They were pulling out control rods in an effort to start the reaction up. But they made a fundamental mistake with reactors. The control rods control rate of change, not the absolute power rating. So when the reaction did start up, it rapidly overloaded the reactor. On top of that, the reactor was designed with a positive thermal coefficient. English translation: the hotter it gets, the faster the reaction runs. No wonder the damn thing exploded. Its like Windows, when you see how well it was designed, its no wonder it gets hacked.
But this is old technology. Look at the more recent technologies like pebble reactors. They figured out the maximum temperature a reactor could hit, and then designed the ceramic shell to melt at a higher temperature. It can't melt under its own power. Its passive safety, which I trust a lot more than active safety with all its pumps and valves and moving parts that can fail.
TMI was within a couple of hours of a *total meltdown* before they finally figured out what was going on
According to the Kermey (sp?) report, the reactor actually melted down about 25-50%. The reactor designers were quite conservative. They assumed that steam would not cool the reactor core at all. In reality it cooled about half as effective as water. So in spite of the operators turning off the ECCS (emergency core cooling system) pumps, the absolute wrong thing to do, the reactor didn't completely melt down.
it's not a given that the containment building would have stopped a liquid pool of molten nuclear fuel from eating through down to the water table
Kermey report actually goes into that. TMI-2 had a relatively new reactor load, therefore had few waste products built up. It would not have penetrated the containment building. I think the doc even questions if it would eat through the reactor vessel. Its been years since I've read those docs, so memory fades a bit.