World's best cars by fuel economy,
that can hold at least 4 adults, and go at least 130 kph (80 mph),
as of 2009.
I took almost all this info from vcacarfueldata.org.uk. These are the "extra urban" numbers, roughly comparable to highway mileage. Most of these cars are very small and light "city cars".
2009 Toyota Prius (ZVW3)* 76.4 3.1 gas
Ford Fiesta ECOnetic 73.5 3.2 diesel
Volkswagen New Golf (1.6 TDI BlueMotion SE) 69.2 3.4 diesel
Fiat Grande Punto (1.3 16v multijet 75) 67.2 3.5 diesel
Mini Cooper (Hatchback R56) 67.2 3.5 diesel
Mazda Demio(1.4) 67.2 3.5 diesel
Volkswagen New Polo (1.6 TDI (75 PS) SE) 65.4 3.6 diesel
Fiat 500/Fiat 500C (1.3 16v multijet) 65.3 3.6 diesel
2009 Toyota Prius (T3) 63.6 3.7 gas
Ford New Ka (1.3 Duratorq) 63.5 3.7 diesel
Fiat Panda (1.3 16v multijet) 63.5 3.7 diesel
Daihatsu Mira* 63.5 3.7 gas
Fiat Bravo (active ECO 1.6 16v multijet 105) 61.9 3.8 diesel
Fiat Qubo (1.3 16v multijet trekking) 61.9 3.8 diesel
Suzuki Alto (1.0) 61.9 3.8 diesel
Citroen C1 (1.0i) 60.3 3.9 gas
Opel/Vauxhall Agila 1.3CDTi 58.8 4.0 diesel
Suzuki Splash 1.3CDTi 58.8 4.0 diesel
Toyota Aygo 57.4 4.1 gas
Kia Rio (1.5 CRDi Oct 2007 onwards) 57.4 4.1 diesel
Peugeot 107 57.3 4.1 gas
Nissan Micra (1.5 dCi 86 from Sep 2007) 56.0 4.2 diesel
Kia Picanto (1.1) 56.0 4.2 gas
Toyota Prius (1.5 VVT-i) 56.0 4.2 gas
Hyundai i10 (1.2) 54.7 4.3 gas
2010 Honda Civic hybrid 54.7 4.3 gas
2009 Toyota Yaris (1.33 TR VVT-i) 53.5 4.4 gas
Daihatsu Sirion (M300 1.0L) 53.5 4.4 gas
Subaru Justy (1.0) 53.5 4.4 gas
2010 Honda Insight hybrid 52.3 4.5 gas
Mini Cooper (Hatchback R56) 52.3 4.5 gas
Volkswagen New Beetle (1.9 TDI) 51.1 4.6 diesel
Proton Savvy 51.1 4.6 gas
Chevy Aveo (1.2 S 3) 51.1 4.6 gas
Mitsubishi Colt (1.1) 49.0 4.8 gas
2010 Toyota Yaris (1.0 VVT) 48.0 4.9 gas
Mercedes A 150 (BlueEFFICIENCY 185) 47.0 5.0 gas
Mitsubishi i (0.66) 46.6 5.0 gas
Ford Focus (1.4 Duratec) 44.4 5.3 gas
Chrysler PT Cruiser (2.2) 42.0 5.6 diesel
*Didn't see these cars on the British site, so the fuel economy figures
1 liter/100 km = 282.48 mpg (imperial gallon)
1 liter/100 km = 235.21 mpg (US gallon)
It's surprisingly hard to run fuel economy info down. Wikipedia generally doesn't have it. Manufacturers are both coy and afraid of regulation, and when they have the info at all, bury it behind a wall of marketing, and leave out details such as whether they used imperial gallons or US gallons. The official government sites are a total pain to use. They couldn't just make a nice list, oh no, they make you select every single car, one at a time, and shove the meat several links behind the selection screen.
Some of these cars are merely rebranded. The Toyota Aygo, Citroen C1, and Peugeot 107 are supposedly the same car.
I think the car with the lowest top speed in this list is the Mitsubishi i, at 84 mph according to the manufacturer.
The Brits test differently than the US, and get higher fuel economy numbers. Also, the cars aren't identical. US versions end up weighing more because the US has more stringent safety requirements. The versions with the smallest engines, and the best fuel economy, are available in Europe but not the US.
What makes me furious is that almost none of these cars can be had in the US. You can't buy them outside the US and bring them in either, without such extensive modification as to make it not worth doing. Those that we can have are clustered at the bottom of this list. We can ride motorcycles, and drive "unsafe at any speed" antique cars, both of which are far more dangerous, but we can't have these cars. Perhaps one way to work around the problem is to get the engine only, and put it in an antique.
I had to google/image a bunch of these cars to just see what we were talking about. The Toyota Aygo looks just like a Honda Fit!!!
Makes me furious to no end that our gov't will spend millions (Billions in fact) on such things as cash for clunkers but if they lifted some regulations and lightened a few standards we could MAKE money off letting these other manufacturers sell their cars over here... and get twice the mileage, reducing our need for foreign oil, making us more independent. It would also stimulate more jobs because we'd need new mechanics to work on them/dealers to sell them.
It isn't all the government. Some of it is the companies, but mostly it's the consumer here. As was brought up in another thread, for most new car buyers fuel economy isn't as important as we rank it. Plus, the the frugal person isn't going to buy a new car.
And heaven forbid the general public getting a smaller car with roof rack, or even a small trailer for the few times they actually need extra cargo space. Nope, got to drive an oversized vehicle that is under utiliser 99% of time instead.
This list is 5 years out of date now, there are cars that get close to 100 MPG now, i'm pretty sure if your fuel was $10.65 a gallon like it is in the UK, you'd probably want a car this good on fuel too!