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Early Contenders for the Automotive X-Prize
longacre writes "With the official entry period for the $10 million Automotive X-Prize contest just around the corner, Popular Mechanics offers a preview of the most promising entries. Among the 100-mpg vehicles that Detroit (and Japan) have claimed impossible to build comes a hybrid designed by a class of inner-city high school students in West Philadelphia. Also displayed is a futuristic-looking electric model with a range of 300 miles. We discussed the beginning of this contest earlier this year."
> Among the 100-mpg vehicles that Detroit (and Japan) have claimed impossible to build...
I know it is fun to rip on 'evil' corporations and all, but there is a bit of difference between some glorified go-cart some kids cobble together and what will pass the Dept of Transportation crash tests. Detroit and Tokyo live in the world where trial lawyers will rip ya a fresh asshole if a jury can be convinced your design wasn't 'perfectly safe.'
Democrat delenda est
[quote]What do ya think you will do with that car? This is the question I have for most of these exotic vehicles.[/quote]
:)
:) Let's *actually* run the numbers.
Commite, shop, and all of the stuff I normally do with a car except for long trips**. Duh.
[quote]Based on their own numbers you get a 120 mile distance to dead so you wouldn't want to get more than forty or fifty miles afrom home[/quote]
Depends on whether there's merely a normal household power socket on the other end, but let's go with that. So?
[quote]and that is going to be with the climate control off.[/quote]
Small car, efficient heat pump, solar-powered climate assist. Sure, it'll impact range, but probably not as much as you're picturing. Also, there's no initial cooling load, as it has a solar-powered vent fan that keeps the car just above ambient temperature when you're not in it and it's out in the sun.
[quoteFrom their webpage it looks like you can get a hybrid drive as an option but they don't have any details as to how much cargo space you sacrifice for the gas engine/generator.[/quote]
None. The generator displaces 2/3rds of the batteries; it has a shorter electric range, but the 5-gallon gas tank gives it a range of 600-700 miles.
The Aptera has 15.9 cubic feet of cargo space.
[quote]Lets run the numbers. Assume a commute that runs 35 miles, 70 both ways. On a good econobox you can get 35mpg so it works out to two gallons per day or assuming gas hits $5/gal you pay $10/day for gas. Average of about twenty work days per month and ya get $200 for gas to commute. Now compute the difference in the monthly note for the econobox and the savings on the light bill from not plugging in every night and gulping down a few KWH (remember it takes more than 10KWH to charge a 10KWH battery) and it's probably a wash. If your commute is less the economics get worse pretty fast.[/quote]
I find it funny that you said "let's run the numbers" and then didn't actually run the numbers. That's pretty amusing.
Econobox: $13k, +$2k in taxes, -0k deductions.
Aptera: $27k, +3k in taxes, and let's assume that deductions roughly cancel out taxes (could be a lot more, but let's be pessimistic).
Price difference: $14k
$10/day = $3650/year
Aptera goes 120mi on 10kWh = 80Wh/mi (0.08kWh/mi). Charging is usually ~93% efficient, but let's be pessimstic and say that it raises power consumption to 0.09kWh/mi. I pay $0.05/kWh, but the average in the US is more like $0.10/kWh, so let's go with that. That's 4/5th of a cent per mile. * 70 miles, * 365.24 days, that's $230/year.
Net savings: $3420/year. Time to pay off the difference: 4 years.
See what happens when you *actually* do the math? Electricity is dirt cheap, and the Aptera uses very little of it.
There's also maintenance, but when you consider that a good lithium phosphate pack should last the life of the car, and even if you had to replace it, by the time you had to replace it, LiP should cost under $0.20/kWh, you're only looking at a couple thousand dollars thanks to the small pack size (thanks to the efficiency). I.e., it'd cost far less than you save by eliminating 90% of the moving parts in the drivetrain compared to a normal gasoline car. It doesn't even have a transmission, let alone all of the breakable parts of an ICE. So the payback time is even sooner.
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
In fact, what's with mileage going DOWN over the last 15 years?
Look at the horsepower. Given the same engine size and roughly the same fuel, for the most part,additional efficiency has been applied to produce more horsepower to the engine. In the 1980s and even into the 1990s, fuel efficient cars were so utterly anemic that the best thing to do to get any kind of performance would be to buy a truck or a 1970s muscle car.
No more.
Nowadays, you've got 4 cylinder engines supercharged up to 300hp, and GM's new V6 in the Caddy CTS is a naturally aspirated 6 that makes the same horsepower as the V8. If you want a V8, you are usually talking at least 350 hp to start, going all the way up to 500 or even close to 600 hp once you put a blower on it.
Just look at the 0-60 times. First 7 seconds was good for a stock car, then 6, and now mid 5's are common. A supercar gets you to the speed limit in 3 seconds.
Speed sells. People like to go fast and accelerate quickly, and that is what car makers made.
Most people aren't mad about the price of gasoline, except in a bitter sense, because they intuitively know that Detroit didn't victimize them - 35mpg cars have been there all along, and they know it wasn't some crazy oil conspiracy. Rather, they know it was their own dumb fault for buying a gas guzzling vehicle when we should have learned having been burnt by this first in 1973, then 1979, and certainly we would be burned again.
The thing is, yeah, the price of gas sucks. But everyone knows that the pandering by all of the candidates is not the real solution. I mean, sure , idiots can rise up like Obama blaming the "oil companies", or almost as nearly as bad, McCain trying to get the gas tax repealed, but, if you ask most people if they would rather have just drilled the shit out of the country to get every last drop of oil, turned Colorado into looking like the moon in order to get all the shale, many, shockingly, (and I would almost say foolishly) would rather preserve the environment. I guarantee you, if you really wanted to lower the price of fuel, you could put in the right environmental waivers and tax breaks, blow off global warming, and we'd be back to about $2/gallon gasoline within 3 years.
Really, most Americans intuitively know that they need to get out of their low mileage vehicles, and get higher mileage vehicles, if they are so pissed off about fuel. For some, its the environment and concerns over global warming. For some, cars aren't mystical beautiful things, just transportation and they'll consider the train. For some, its a racial hatred of arabs and a political hatred of chavez. So really, no matter how you arrive at it, a bit of conservation either saves the planet, screws the arabs, and saves some money, so, really, it's all good.
This isn't stuff we didn't know about before, but we know that now is the time to get on it.
This is my sig.
I assumed anyone at slashdot could take the math the rest of the way and apply it to their situation but apparently you need some help with yer figuring.
Clearly you're not in finance. All of these mathematical calculations are wrong in the face of finance. By finance I'm not talking the terms banks and lenders throw around as a verb, I'm talking about the finance department of any company to compute the feasibility of a project or investment. For example everyone likes to use the "pay back period" as a financially sound way to compare two projects when it ignores a critical factor: the time value of money.
So now you claim the original post not to "take the math the rest of the way" when you've clearly got some issues in your math. To settle this, I'll do a decent job in taking the math all the way by giving you a fairly sound financial computation on net present value. I'm no finance person, but I've been in accounting and finance classes to know that your calculations are wrong and there are better ways. So since you asked, here is your math problem solved correctly.
There are two common ways to compare to streams of cash flows financially: internal rate of return, and net present value. The easier one to understand (and also with fewer math issues) is net present value. All net present value is is taking a stream of cash flows and calculating their values in dollars at the current point in time. As you know, a dollar today is not worth the same amount as a dollar next year due to inflation and other things. Net present value accounts for this by introducing the risk free interest rate into the equation so that you can get two sums of money to compare at a single point in time.
Before I go further, I need to say that dividing the fixed investment cost and time zero (today) over the lifetime of the investment is wrong for time value of money reasons. That is when you buy a car in pure cash today, you cannot receive the benefit of reinvesting that cash because it is gone! What you can do is say you spent X dollars at time zero and if at the end of the useful life, you sell the asset, then you will receive some money back but quite a bit less due to depreciation and market value at the point of sale.
In order to compute the net present value, all you have to do is take the present value of each year or month's cash flow and compute the present value of that item. So for example let's assume the risk free rate is 2.5% and because we don't care about the rate of return (this is not really an investment to make money, but to save money and fill a need), all we care about is the risk free rate. So today a dollar is worth $1. Next year the same dollar invested today will be worth $1 * (1.025 ^ 1) = $1.025. (You can also think in the other direction and say that a dollar in the future by one year is worth $1 / (1.025 ^ 1) ~ $0.97561 today.) As you might guess, a dollar invested today will be worth $1 * (1.025 ^ 2) = $1.050625. If we keep doing this for 5 years, the factors for each year are:
So let's do the real financial math to compare costs. In order to do this, we need to compute how our cash will flow for each investment. I will reduce the calculations to years since it is easier to show, but you could also do the calculations compounded by month if you wish by dividing the interest rate by 12 and recomputing the multipliers on a monthly basis (or use Excel's net present value function hint hint). We will also assume that both cars depreciate at a rate of 20% a year so in 5 years, they will be worth (1 - 0.20) ^ 5 = 32.768% of their initial value and we will find a buyer that is willing to pay that exact value for the asset at the end of the year. That means after 5 years we will sell the econobox at $4,915 (rounding off 20 cents) and the Aptera at $8,683 (rounding off 52 cent