UK owners... MPG imperial or US gallons ?

Sorry to disappoint you, but your MFD is using imperial gallons to calculate mpg, so your display of 50mpg is about 41.7mpg (US gallon).

I've proved this with my fill ups since new (Mar 08) and the MFD is only ever about 1-2 mpg different from the actual fill up calc.

The figures you see quoted from our American friends are much better than our equivalent, which goes to show the lengths you still have to go to get great mpg like them.

My best ever run was 61 mpg over 300+ miles. Converted back to US gallons it was about 51mpg - no great shakes for the US hypermilers. But I am really happy with that so I don't feel bad at all (and it beat the US EPA figs so double happy with it).

Gotta lot to learn yet.......

 

I don't think you necessarily have a lot to learn as much as your road system and typical commute is much different from ours. I frequently travel to the UK. I have dual citizenship (my mother was in the US Navy and my father in the Royal Navy) and travel to visit my family relatively often. With an exception to the members here in cities such as NY, Chicago, etc, the rest of the country is pretty spread out. A good chunk of us live in the western part of the country and we're spread out further still. Our typical commutes are on packed interstates commuting 20-40 miles round trip or more over relatively straight road systems. Americans for the most part have not learned to work within proximity of their home. As an employer, I still get resumes from folks that live 50+ miles away for a relatively low paying job. During our commutes we can drive 40-60 mph for long periods of time if we leave enough room in front of us (many of us can at least). This is the optimal speed for the Prius. I can easily get 60-75mpg on my commute to work. In fact I only get low 50's because during the weekends I'll drive 85mph everywhere I go, and it brings my mon-fri average down.

In contrast, I've found in England many live closer to their homes and many take advantage of alternate means of transportation such as public or walking. Those that do drive, drive relatively low distances compared to many Americans. Driving short distances decreases Prius MPG drastically due to the warm up cycle. You're also very congested within the cities, but open up and sustain a much higher overall speed on the motorways. Both lowering MPG.

I made a point on another forum when someone was talking about Ford bringing the Focus diesel to the US. The article cited 65mpg. After I converted this MPG to American numbers (US Gallon as opposed to Imperial Gallon), I made the point that I believe a diesel engine is better suited for the type of driving that I've experienced in the UK. This driving being a combination of shorter trips or when the trips were longer they consisted of higher top speeds...

My Prius is 11 months old and turned 20,000 miles this past weekend already... and I own 3 other vehicles to give you an idea of how many miles I drive. I work Mon-Fri and my commute is 20.5 miles each way. Many of my miles are wasted on needless trips. Most Americans will drive to the other side of the city for the smallest errand, then back... just to drive to the other side and back 2 hours later for something else. These longer trips at a relatively low speed help our overall fuel economy.

Friday evening on the way home from work I filled up the Prius at the fuel station within a mile of my house. My wife made a handful of trips in the Prius on Saturday and Sunday. Because my MFD was reset, my average MPG was based on my weekend "running around". On Monday, my mileage was either 41 or 44mpg (I forget). It's now Wednesday and I'm at 49MPG already. I've allowed my longer trips to bring my overall average up. By the weekend I'll be in the 53mpg range. Over the weekend I'll probably drop back down to around 50mpg. Monday will come and I'll be around 51.5 after getting to work.... I'll fill up sometimes Tuesday and I'll usually be around 51.8 - 52.5 and the cycle will start all over again. Hopefully I didn't bore you... but just wanted to illustrate how different driving patterns greatly affect fuel economy.

 

We try to do this so we don't get lost

Interesting post and not boring. nice to hear of your UK driving experiences, which certainly ring true with me. The comment about your wifes mpg also rings true with my better half, although she is now watching the MFD mpg and I get a rebuke when it starts dipping.
Diesels are ok, my last car was a diesel Audi A4, but the mpg was not great at all, much worse than the Prius. I never kept a log but I know from miles on the trip meter and litres filled up it was averaging 35-38 Imperial mpg. Not too shabby compared to some gas guzzlers but nowhere near as good as a Prius on the same route. Even longer distancex, the Prius is still better than the Audi was, although I tend to drive within the speed limit now....