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While the modern diesel engine is still a bit of a novelty here, it’s the default engine in Europe, and is usually the volume seller in many a model range, luxury ones included. There’s no sign of this trend waning, and we’ve seen CO2 figures pushed down and power figures pumped up over the years. Now, Renault has what it hails as THE diesel engine family boasting high tech for regular cars.

It’s called the Energy family, and the first to appear is the dCi 130, a 1.6-litre diesel that will be launched in the Scenic and Grand Scenic MPVs before powering the Megane range. This unit will supersede the long serving 1.9 dCi 130 (F9Q) in line with the downsizing trend.

The 1.6L Energy dCi 130 is the world’s most powerful engine of its size, Renault says. It makes 130 hp and 320 Nm of torque at 1,750 rpm, 80% of which is available from 1,500 rpm. That’s about the same as what the Focus TDCI’s 2.0L Duratorq makes, but with max twist produced 250 rpm lower, so it’s an impressive effort.

At the same time, combined-cycle fuel consumption is 20% better than the 1.9 dCi engine it replaces, while CO2 emissions have been slashed by 30 g/km. Renault says that with the Energy dCi 130, the Scenic/Grand Scenic will be the most frugal MPVs on sale with CO2 emissions of 115 g/km and fuel consumption of 22.7 km/l. Compared to before, potential range on a full tank is up by 300 km.

Working from a clean sheet, the Energy is said to carry over a number of technologies developed and fine-tuned by Renault’s F1 engine den at Viry-Chatillon. Philippe Coblence, the design office manager for this R9M project, used to work at Viry.

The F1-inspired features include a so-called ‘square’ architecture. The engine is said to be square when the piston stroke is similar to the diameter of the cylinder (bore), an arrangement which allows large-diameter valves to be housed in the cylinder head for more efficient filling of the combustion chambers. This helps performance. Other measures are transverse water flow cooling technique that allows for a smaller, less energy-consuming water pump. This has been combined with a double water jacket arrangement for the cylinder head.

Super-finishing and special surface treatments as well as UFLEX oil control ring technology also feature in the Energy. The U-shaped geometry is highly flexible and enables the ring to adapt to bore distortion to achieve the best compromise between efficiency and friction. “The principle is comparable with that of a multi-blade razor. It adapts naturally to the contour without having to exert high pressure on the cylinder wall. The result is maximum efficiency and less friction,” Coblence explains.

This ‘unprecedented high-tech package’ contains over 30 patents, according to Renault. Of course, existing tech from higher up engines such as VGT, Stop & Start plus cold-loop, low-pressure exhaust gas recirculation (EGR) are present. Alliance partner Nissan, which co-funded this project, should also benefit greatly from it.