Seat is serious about accelerating: the manufacturer offers four models with an air-fueled propulsion system, and is now involved in a research project aimed at producing biomethane directly from waste. How the only compact SUV with natural gas drive, the Arona, beats in practice, says our driving report.
The marketing machinery for electrification is running at full speed in the Volkswagen Group. But in Martorell near Barcelona, they continue to use another alternative form of drive: the natural gas engine. The Arona model is currently the only one in its segment that can be powered by this fuel. And with petrol, because, as is well known, the network of petrol stations has not yet developed as much as customers would like.
TGi - the TSi is so clean
Under the hood runs the one-liter three-cylinder, which is also used in other corporate models. For the Arona, it is optimized for natural gas combustion and provides 90 PS (66 kW). At the rear he carries the abbreviation "TGI", which stands for "Turbo Gas Injection". The additional costs compared to the comparable TSI version are moderate 1000 Euro. The clean petrol engine has five horsepower more, but only a five-speed gearbox. The TGI uses a six-speed manual transmission.
The seriousness with which Seat continues to focus on natural gas is evident not only in the fact that it follows the EU-funded and four-year project for the recovery of landfill gas from waste. The Spanish brand trusts that an increasing number of customers will opt for the variant because of the environmental and cost advantages. It is investing millions in expanding the production of natural gas vehicles. Output at the Martorell plant is expected to ramp up from 95 to 250 units daily.
MQB as a bag of tricks
Since the Arona is based on the platform of Ibiza, he is not good for the space miracle. Especially if the front occupants are really comfortable, the rear seated passengers must expect restrictions in their legroom. While there is room for 1,40 meter in front between the door panels, there are still 1,36 meters in the back. The 1,55 meter high body leaves all passengers enough headroom. The loading opening behind the tailgate is 1,08 meters wide.
Setting a natural gas facility at a mere 4,14 meter long car, designed and built for conventional gasoline operation, poses some challenge. The pressure vessels holding 13,8 kilograms of natural gas are located at the rear, resulting in an increase in the load compartment floor would have. Instead of 400 liters of luggage in the TGI only 282 liter available, with folded rear seat backs are 1162 liter. The backrest is divisible, so that up to about 1,70 meter long objects and three passengers can find space. The gas tank as iron reserve has a volume of nine liters. The gas and fuel tank indicators are disconnected, a green pilot light indicates natural gas operation.
It's so easy to fill up with CNG
Thanks to standardized connections, refueling is just as easy as with petrol. Attach valve and lock, with a button on the column, the pressure filling is started. At current prices between 1,10 Euro and 1,20 Euro per kilogram a full tank for 16 Euro is available. To experience something like this at the gasoline pillar, only elderly drivers can remember it. The range gauge of the test car then reported 380 kilometers. Diesel drivers can only smile mildly. And that's a problem with the otherwise pleasing and practical Aronas: Because of the limited space available, a larger gas tank would mean even more boot loss, and so you have to compromise on the range.
Another problem is consumption. To generate a reasonably fast driving experience with 90 PS and 160 Newton meters torque, you can quickly get into higher speeds. Like its petrol counterpart, the three-cylinder is designed for 5500 tours, but from 3000 revolutions per minute you have to expect unpleasant effects on fuel consumption. If you drive for a while on the highway, you will notice that the consumption tends to skyrocket, even if you start from a level of, for example, 4 kilograms per 100 kilometer. The test cycle of this Aronas was completed with an average consumption of 4,6 kg / 100 km, which was 0,5 kg above the catalog value. Converted to Euro per kilometer, this means the cost of about 5,3 cents per kilometer.
Since Seat also offers a 1,5-liter four-cylinder for CNG (Compressed Natural Gas), the question must be allowed, if this would not be the better propulsion for the Arona. A Leon test car with this unit can in practice reach 4,1 kg / 100 km - mainly thanks to the lower average speeds. That the pithy-sounding three-cylinder might be better suited to a compact SUV because of its rustic acoustics, was at liberty. Incidentally, instead of the factory-specified maximum speed of 172 km / h, the test car managed GPS-measured 177 km / h.
Increasing demand can only be expected of all manufacturers of CNG passenger cars, because then the number of filling stations will rise as well. No one can care less about the extinction of the burner, and many suppliers are already plaguing gloomy future prospects. The natural gas engine of the Seat Arona has indisputable emission and cost advantages on the short- and medium-haul routes, but draws the short straw compared to larger-volume natural gas engines when traveling over long distances.
Data Seat Arona 1.0 TGI
Length x Width x Height (m): 4,14 x 1,78 x 1,55
Wheelbase (m): 2,57
Engine: R3 gasoline engine, 999 ccm, turbo, direct injection
Power: 66 kW / 90 PS at 4500-5500 RPM
Max. Torque: 160 Nm at 1800-3800 rpm
Top speed: 172 km / h
0 acceleration to 100 km / h: 13,2 sec.
Tank volume CNG: 13,8 Kg
Tank volume gasoline: 9 L
WLTP Average Consumption: 4,1 Kg
Test consumption: 4,6 Kg
Efficiency class: A
CO2 emissions: 109 g / km (Euro 6)
Empty weight / load: min. 1308 kg / 402 kg
Boot volume: 280-1162 liters
Tropic: 10,6 m
Basic price: 22 320 Euro
Test car price: 27 674 Euro