Good bye Audi, welcome Prius!

Only about 6% of cars sold in Japan are foreign makes (mostly German), but Kanagawa prefecture and its capital Yokohama have one of the highest rates of import cars in Japan. Yokohama is one of the two major ports (the other is Kobe), it has a relatively long history of exposure to Western influences and on average is relatively wealthy. Even so, the street where I live in a middle class neighbourhood is unusual for actually having more foreign cars than Japanese ones.

Until very recently the count was as follows:

  • Mercedes Benz: 4
  • BMW: 3
  • Volvo: 2
  • Audi: 1
  • Porsche: 1
  • Toyota, Nissan and Honda: 4

Since then the numbers changed because I sold my Audi A4 and bought a Toyota Prius. Who knows what’s going to happen when the only German in a street in Japan where German cars outnumber Japanese cars trades in his German car for a Japanese one? 😉 It’s going to be interesting.

The first time my wife and I washed it in front of our garage, neighbours from two houses came over to take a look at it and to talk about it. One couple, who have a BMW X5 were very curious. They explained they only get about 6 km per litre (17 litres per 100 km) and were thinking about what to replace their car with. The other, who drives a Volvo came up as soon as she saw her neighbours across the street talk to us. Afterwards, the wife of the BMW driver said: “Minna eko ni shimashô!” (“Let’s all go green!”)

I expect we will see more hybrids in our street soon.

I’ve driven Audis (or Volkswagens based on Audi designs, such as the VW Passat) since I got my first car in 1982. Generally I have been very happy with them, especially an Audi coupe quattro 20V I had from 1989 to 1994. The latest Audi A4 2.4 however that I bought in 2000 was heavier and seemed not as well made as its predecessors.

The A4 was fun to drive when I bought it second hand with only 3000 km on the clock, but its V6 engine was never anywhere near as fuel efficient as my previous five cylinder engined Audis, nor was it quite as reliable.

After spending more than $2500 on repairs in the final year alone while consistently getting only about 320 km of range out of a 53 litre refill of premium unleaded (98 octane RON), I was starting to worry for the future of that car.

Even allowing for the fact that most of our trips are short runs to the station or to shops, usually less than 10 km total, with the engine starting from cold much of the time, that 16-17 litres per 100 km (6 km per litre) that I was getting was simply way too much. The best I’d seen was around 12 km per 100 km (8 km per litre) on long highway runs on a ski trip.

Then one day last winter I took my daughter to an entrance exam at a junior high school. As I was waiting near the school, a Toyota Prius rode past me in “stealth mode”, running only on its batteries without any engine noise. It was almost as quiet as a bicycle. My curiosity about this car was awakened.

I had heard various rumours about the Prius, such as about limited battery life and started to check out the facts. I found the batteries did not need replacing every couple years and were expected to last as long as the rest of the car.

The more I read, the more I was fascinated how much thought the Toyota engineers had put into this car and how methodical they had been about making it work in real life. The Prius has been around in Japan since 1997, even though relatively few of that first generation were sold until 2000, when the second generation came out, which went into export markets too. Even before the Prius, Toyota had already been gathering experience with the RAV4 EV, a plug-in electric. The 1.5 litre engine in the Prius is a close cousin of the identical sized engine in the Yaris / Vitz / Platz ranges, but using the more efficient Atkinson cycle instead of the Otto cycle. Its peak efficiency is 34%, better than some diesels. By giving up on peak power and peak torque (which instead are provided via the battery and electric motors), the engine can be much more efficient.

Later in February my Audi needed more repairs and this time I had a Toyota Corolla as a loan car. It made me consider if maybe I would be better off in something lighter and more economical than the Audi and I was curious what a Prius would be like.

In March I went to California on a business trip. A friend there whose wife drives a Prius let me do a short test drive. Pulling away from a traffic light, where the engine had been automatically stopped, felt very unusual: The car starts up running only on its electric motors, without the noise of the engine, which comes alive only as you already start rolling.

Finally in late June my wife and I started shopping around for a buyer for the Audi and for a good deal on a Prius. The waiting list from custom order to delivery turned out to be about 5 weeks, far less than I had seen quoted by US-based posters on websites. I went for the “S Touring” model with a navigation system as an option, which my wife had been requesting for years. The touring comes with HID headlamps (I had never been happy with the conventional halogen lights on the A4) and a firmer suspension than the base model.

We also added a gadget called “etc” (electronic toll collection), which handles toll road charges for motorways here in Japan (most motorways here charge for usage). There are special lanes for etc-equipped cars at toll gates, which make it quicker to get through, as you just have to slow down to 20 km/h to pass through while your car contacts the wireless booth equipment. Before we always had to queue in a line to hand a prepaid card, cash or a credit card to a guy in a toll booth. There are discounts for paying by etc, I guess because the operating company can cut back on staff.

We returned the Audi on the day its bi-annual vehicle inspection became due. We then relied on bicycles and public transport for four days, until the Prius arrived on the last day of July.

Only after I placed the order did I google for crash test results, but the outcome was very comforting: Though the Prius was some 200 kg lighter than my 1999 model Audi, it did as well as the latest A4 model (2008) on crash test results. In fact it had the highest rating of any car tested for kids in child seats in the EuroNCAP tests. As far as interior space is concerned, I didn’t have to give up anything. If anything it’s more spacious than the Audi and it offers the practicality of a hatchback.

Last weekend we drove down to the coastal town of Enoshima on the Pacific, about 35 km from here, which on a Sunday takes 1 1/2 hours because of traffic jams. The Prius will simply shut down its engine whenever stopped, whether at a red light or in slow traffic. Even then the air conditioner (essential at 30+ centigrade in hot and humid Japanese summers) will keep you comfortable, as it’s electrical and draws current from the car’s powerful traction battery that also drives that car’s electric motors.

The NiMH battery will get recharged when the engine is running again or whenever you push the break pedal to slow down the car, which switches one of the motors to work as a generator. This “regenerative braking” extends the life of the brake pads too.

Other auxiliary systems that on conventional cars are driven directly by the engine via a belt are electric on the Prius, such as the power steering and the brake servo. These always suck some power on conventional cars, whereas on a hybrid they only draw power when needed, making it more efficient.

On the way back we also drove at 80-90 km/h on multi lane highways, with the multi function display (MFD) showing better than 20 km per litre (better than 5 km per 100 km). We never had any trouble keeping up with traffic.

UPDATE (2008-08-10):
With about 250 km on the odometer, the displayed fuel consumption average is now around 16 km per litre (6.25 km per 100 km or 38 mpg US). Other than the weekend trip, it was mostly short trips to a shop or to drop off or pickup a family member at one of the train stations, which are about 3 km away. At our average of about 900 km per month this means the Prius is burning some 90 to 100 litres of fuel less per month than the Audi A4 it replaced, as well as running on a cheaper grade of fuel (regular instead of premium unleaded).

According to the website of the UK Department for Transport the Prius is not the car with the lowest CO2 output per km in Europe: It is undercut by two other cars. The Polo 1.4 TDI Bluemotion and the SEAT Ibiza 1.4 TDI Economotion both use the same 80 PS VW/Audi turbodiesel engine. At 99 g/km they output about 5g less CO2 than the Prius. However, these cars are classed as “superminis”, which offer considerably less space to passengers. Most people fail to realize how spacious the Prius really is compared to its competitors. Based on interior space the EPA in the US actually puts it into the “mid-size” category, along with the BMW 5-series and the Audi A6. Below the 5-series and A6 in size are the 3-series and A4 (rated as “compact” cars by the EPA). Below that is the A3 / Golf / New Beetle (“minicompact”). And one more size below that are the Polo and Ibiza.

UPDATE 2 (2008-10-16):

In two and a half months of ownership, our Prius has clocked up over 2500 km (1530 miles). My daughter accidentally reset the average fuel consumption display after 100 km, but in the 2400 km since then the car has averaged 18.9 km/l or 5.3 litres per 100 km or 44 miles per US gallon.

Keep in mind that most of our trips are to pick up or drop off a a family member at a station 3 km away, so most of our trips are no more than 6-7 km on a cold engine. Also, almost all our driving is urban, with plenty of traffic lights / stop and go traffic. If your average trip is longer or you drive more across country or if you live in an area that’s flatter than hilly Yokohama then you’d probably see even better fuel economy from this car.

Toyota Prius hybrid versus BMW diesel

The Sunday Times did a road test, driving a BMW 520d SE and a Toyota Prius from London to Geneva. The BMW used 49.3 litres of diesel, versus 51.6 litres of petrol (gasoline) used by the Prius.

While the BMW’s results are clearly respectable, the figures quoted in the Sunday Times article do not tell the whole story.

For a start, about 40% of the trip were on motorways, another 40% on B-roads and the rest in urban areas. A driving mix that includes only a token 20% of urban driving is hardly typical for usage patterns of most motorists in our largely urban / suburban societies (for example, 79% of the US population lives in urban areas, with most European countries having similar rates). This unusual mix seems almost purposely designed to ensure that the advantage of the hybrid drive train of the Prius would lie mostly idle: Driving at constant speed on a flat road, you are not going to see any real benefits from a hybrid system, which really thrives in stop-and-go rush hour traffic with lots of traffic lights, as most of us experience on the way to work or home.

Secondly, even with these skewed parameters, the BMW lost out on greenhouse gas emissions. It burnt 10.84 Imperial gallons (13 US gallons) of diesel, while the Prius used 11.34 Imperial gallons (13.6 US gallons) of gasoline. Because of diesel fuel’s 15% higher carbon content by volume, the BMW added 131 kg of CO2 to the atmosphere versus 120 kg by the Prius.

Personally, I see no reason why in the long-term efficient diesel engines can not be mated to a hybrid system and have the best of both worlds. Sure, it may not yet be cost-effective at current fuel prices, but things may look very different 10, 20 or 30 years down the road.