If there was ever evidence that a downward push on CO2 emissions is a global and industry-wide concern, then the luxury sector is among the best there is. Diesel dominates this sector in Europe, but Jaguar has shed two litres from the XJ’s engine capacity this year, showing even the biggest petrol-powered limousines are cutting costs.

Although this is a small segment, it’s fiercely competitive and standards are very high. It’s also dominated by the Mercedes-Benz S-Class, the three-pointed star’s spearhead model, which has traditionally set the bar for comfort and technology. This latest XJ may have launched alongside an ageing S-Class, but with a new one just joining the market Jaguar, BMW, Audi and Lexus have some new benchmarks to aim for.

What the XJ does better than most, though, is avoid looking staid. This is a very conservative segment, and where its closest rivals simply look like large saloon cars the XJ is a genuine head-turner. It’s part coupe, part luxury yacht, and there are even elements drawn from the world of aviation to be found inside. The more you look around, the more you notice just how detailed the design is. Jaguar may not be able to match the S-Class for technology, but it’s hard not to feel pampered in its ultra-stylish interior.

Money perhaps isn’t as much of an issue in this sector as in higher volume parts of the market, but most European XJs are powered by the 3.0-litre V6 diesel engine. However, there are buyers who still prefer the outright refinement of a petrol and this new 3.0-litre supercharged unit fits the slot in the XJ’s range. It’s allowed Jaguar to reserve its thunderous 5.0-litre V8 for the Supersport and XJR.

The 3.0-litre V6 is a derivative of the engine found in the F-Type, and as if the diesel wasn’t refined enough, this is a truly blissful experience. There’s a slight whine from the supercharger under heavy loads, but for those who require only the minimum in mechanical noise it’s hard to resist the peace offered behind the XJ’s double glazed windows. Wind noise over the closed sunroof – only audible at motorway speeds and when the cover is open – is a bit of a let-down, though.

The XJ is also a better driver’s car than its closest rivals. It’s capable of effortlessly delivering driver and passengers to destinations feeling with little effort, but slip it into Sport and it’s quite happy to be pushed along at pace. The trade-off is ride quality, which is noticeably more fidgety in this than in the S-Class. It’s really a matter of taste and requirements.

Verdict:

It’s a sign of the times that Jaguar has been able to bring CO2 emissions for the petrol XJ in line with a diesel version of its predecessor. But, unsurprisingly, this is a niche car for those willing to put extra money in to get the most relaxed and refined Jaguar on sale.