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Renault’s New Clio III: Up to 53.5 MPG


Renault has introduced its third-generation version of the Clio (Clio III). Configured with the mid-range 1.5-liter diesel, the Clio III offers fuel consumption of 4.4 liters /100km (53.5 mpg US) combined, and CO2 emissions of 117 g/km.

In 2004, the Clio was the second best-selling B-class car in Europe with a total of 373,738 registrations and a 2.57% share of the total auto market. Up to the end of December 2004, Renault had produced 4.5 million Clio IIs worldwide since the introduction of the second-generation car in 1998, and a total of 8,535,280 units since the launch of the first-generation in 1991.

The Clio III is an important car for Renault. The European small-car segment has been consistently expanding in recent years, rising from 30.8% of the European market in 1998 to 34.5% in 2004. With close to 5 million vehicles sold in 2004, the A and B segments account for more than one-third of European vehicle sales.

The B segment, in which Renault competes with the Clio and the Modus, has grown from 21% of the total market in 1998 to 27.9% in 2004. The diesel mix in the segment has also increased rapidly, climbing to 44.1% in 2004, compared to 19.8% in 1998. Almost half of all Clios sold in Western Europe are now delivered with a diesel engine.

Clio III goes on sale in September with a choice of gasoline and Euro-4-compliant diesel engines. The gasoline engine range comprises 1.2-liter, 1.4-liter, and 1.6-liter 16V units, while the 1.5-liter dCi diesel comes in three power outputs.

It is the mid-powered diesel that offers the best fuel economy.

Select Powertrains for the Clio III
 1.2 liter1.4 liter1.5 liter
Displacement1,149 cc1,390 cc1,461 cc
Power75 hp (55 kW)98 hp (72 kW)86 hp (63 kW)
Torque105 Nm (7.4 lb-ft)127 Nm (93.7 lb-ft)200 Nm (147.5 lb-ft)
Max speed162 kph (101 mph)174 kph (108 mph)174 kph (108 mph)
Acceleration (0–100 kph)13.4 sec11.3 sec12.7 sec
Fuel consumption (comb)5.9 l/100km6.6 l/100km4.4 l/100km
Fuel economy (comb)39.8 mpg US35.6 mpg US53.5 mpg US
EmissionsEuro 4Euro 4Euro 4
CO2139 g/km158 g/100km117 g/km

Digging in a little deeper to the different diesel configurations can provide some insight into approaches for increasing performance and efficiency and reducing emissions.

Clio III 1.5 dCi Diesels
 70 hp85 hp105 hp
Compression ratio17.9:117.9:115.6:1
InjectionSpherical common railSpherical common railTubular common rail
Max speed162 kph
(101 mph)
174 kph (108 mph)190 kph (118 mph)
0–100 kph)
15.2 sec12.7 sec11.1 sec
Fuel consumption (comb)4.6 l/100km4.4 l/100km4.6 l/100km
Fuel economy (comb)51.1 mpg US53.5 mpg US51.1 mpg US
EmissionsEuro 4Euro 4Euro 4
CO2123 g/km117 g/100km123 g/km

The different configuration of the 1.5-liter diesel in the Clio offers 70 hp, 85 hp and 240hp, with maximum torque of 160 Nm, 200 Nm and 240 Nm respectively.

The three configurations are based on the same basic engine unit. All three feature a flexible flywheel with a view to filtering out the effects of acyclic movements and use a second-generation fuel injection system.

But to meet Euro 4 emission requirements, the 70-hp version is equipped with a turbo air cooler, while the 85-hp unit features a 1,600 bar injection system. For the 105-hp version, Renault engineers introduced a lower compression ratio (16:1) and a variable geometry, multi-blade turbocharger.

And speaking of comparisons, it’s also interesting to look at the new Dacia Logan.

In 1999, Renault took a majority (51%) interesting in Dacia, the Romanian carmaker. By 2004, Renault had increased that ownership to 99.3%. In the five plus years of ownership, Renault has pumped almost half a billion euros (US$604.3 million) into modernizing the group.

With its low labor costs (less expensive that robots), Dacia was to be the provider of inexpensive cars for “emerging” markets. In 2004, it introduced the Logan.

The low-cost Logan (€5,000, US$6,000) was originally to sell only in Eastern Europe and Russia. Demand proved so strong, however, that Renault this month began selling the car in France, Germany and Spain.

The Western European version carries some additional amenities and a higher price-tag (€7,500, US$9,000). Renault expects to sell 175,000 Logans this year, increasing to 1 million by 2010, supplemented by the rollout of station wagon and pickup versions.

The Logan is also built on the same Nissan-Renault B-segment platform as the Clio (and the Nissan Micra). Its gasoline engine choices are not as advanced as those of the Clio, however, and despite being a lighter car, it consumes more fuel than its cousin. (A diesel version of the Logan is underway.) The table to the right contrasts the entry level configuration of both Logan and Clio.

Comparing Logan and Clio
 Logan 1.4LClio 1.2L
Displacement1,390 cc1,149 cc
Power75 hp (55 kW)75 hp (55 kW)
Torque112 Nm105 Nm
Weight975 kg1,090 kg
Acceleration13 sec13.4 sec
Fuel consumption (comb)6.8 l/100km5.9 l/100km
Fuel economy (comb)34.5 mpg US39.8 mpg US
EmissionsEuro 4Euro 4
CO2164 g/km139 g/100km

So, in short, the entry-level gasoline Clio, which weighs 12% more than the entry-level gasoline Logan, uses an engine that is 17% smaller, delivers equivalent power and performance, consumes 13% less fuel and emits 15% less CO2.

That encapsulates how enhancements to engine design can allow the downsizing of engines, resulting in better fuel consumption with equivalent performance.

Given the sales expectations for the Logan, however, it also raises a bit of a warning flag. If European automakers are going to meet the 120 g/km CO2 target, pushing out hundred of thousands to millions of inexpensive vehicles with emissions currently 35% above the target isn’t going to help.

Renault needs to do better on the efficiency and emissions attributes of the Logan engines.



That goes to show how much better fuel economy can be achieved without going to expensive hybrids. Diesels produce real world benfits and they would only get better. I've always wondered what the mileage of the Prius would be if all the hybrid hardware is taken out.

Anyway back to this ClioIII, the fuel economy drops compared to the last generation(4.2/100km, 56mpgUS) due to the huge 28% weight gain. Cars just keep getting heavier, but I think in the clios case its a good thing because from roadtests its just as roomy as the megane yet faster and more economical.

Then onto the case of Dacia logan, I myself was shocked that renault didn't use the same engines as the clio. I agree with the author that the Logans fuel economy has to be improved. Toyota used a high tech engine in their Aygo and the results are near diesel fuel economy.


The disadvantage of non-hybrids is that you have no pathway to convert to non-petroleum fuels without horribly expensive and inefficient processing.  A hybrid with a suitable drivetrain can be given the CalCar treatment and run entirely on electricity for short trips and partially for longer ones, which effectively turns any electrical generator into a "motor fuel plant".

There's no way to make a wind turbine run a diesel car... and I speak as the owner of a diesel VW.


Sure you have a non-petroleum pathway right now - biodiesel! Processing it is neither horribly inefficient or expensive. With petrodiesel prices rising, they will get closer to B100 prices soon. (apx $3/gal)
you don't need a wind turbine, you just need our Mr Sun and farmers. :^)


I think E-P and B20 are both on to something. I'd love to see a plot of the percentage of
* hybrid
* biodiesel-capable
* flex-fuel
vehicles on the American road over the timespan of the past 25 years. Is this total growing? At a fast rate? What would it take to get it to grow more quickly? Ultimately, vehicles that can handle blends, bio, or electrical fuel will allow the transportation economy to be more robust against price or supply shocks to a particular fuel. They'll also position the US transportation economy to transition away from petrol more quickly.

Anybody got the data?


Oilseed productivity would require something like 40% of the area of the USA to be planted in e.g. rapeseed to satisfy motor-fuel demand.  That's so not going to happen.

If you can destroy 75% of the demand for motor fuel using plug-in hybrids, biofuels (esp. ones derived from biomass rather than starches or oils) have a good shot at being able to satisfy the remaining demand, but you need a combined approach.


The data exists, it’ll just take a bit to pull it together. Flex-fuel vehicles will likely swamp the other two—certainly hybrids. There are some 4 million flex fuel capable vehicles on the road. (Not actualy using E85, but capable.)

As an aside on E-P’s last point...the amendment proposed by Obama (D-IL) to the energy bill—and that was accepted and so is now part of the Senate package—funds research and development specifically of flex-fuel hybrids, and plug-in flex-fuel hybrids.


Mike:  that's old news to readers here.

Thomas Bailly

RE:" pathway to converting to non petroleum...". There is currently a small on demand hydrogen fuel system thta runs on distilled water and through electrolysis pumps hydrogen into the combustion chamber of any regular gasoline or diesel engine producing a more complete burnand a huge reduction in emissions 50 to 98%, increased mileage 20 to 70% and an increase in power and torque, plus it is cost effective and low maintenance. Check it out at www.burnh2o.com

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