Turn green at the next corner

Can satellite navigation systems, car-to-car and car-to-road communications help reduce carbon emissions?

Society can dream, hope and even plan for a future in which every car on every street of every country in the world will be free from emissions.

But as things stand today, you have to agree with Bente Øverli, a Norwegian consumer ombudsman who famously said two years ago to Toyota and other carmakers that had been advertising their products as 'environmentally friendly': "Cars cannot do anything good for the environment except [be] less damaging than others".

Until cars can be operated, if not produced, without an environmental impact, the focus will remain on improving the efficiency of conventional vehicles. While this is something that carmakers have been doing successfully for decades, inevitably there will come a time when the rate of improvement slows to a crawl.

"You can only go so far in the design of a vehicle to make it as efficient as possible," says David McClure, director of intelligent transportation systems (ITS) and telematics at automotive consultancy firm SBD. "At some stage, the focus has to be shifted from the basic vehicle to the driver."

Since engineers are reaching physical limits in terms of making conventional petrol engines more efficient, their efforts are being redirected at making us more efficient operators of these engines.

Some drivers are already using a set of little tricks to achieve 'hyper mileage' from their cars, usually for economic or environmental reasons. These tricks range from the very basic (removing surplus weight, shifting into a higher gear early, or maintaining a steady speed at the highest available gear) to the most sophisticated (such as using built-in computerised fuel-saving devices).

Drivers will soon find that a host of information and communication technologies are being introduced to help them reduce their carbon footprint.

Green telematics

Most of these applications will derive their connectivity and intelligence from a branch of engineering known as telematics. A common misconception is to think that standard GPS navigation systems are a form of telematics. "On their own we wouldn't call that a telematics system," says McClure. "It only becomes telematics when there's a communication channel, either a one-way broadcast or a two-way link to and from the car."

That said, newer satellite navigation systems are being integrated with wireless links to the car to provide updated traffic data and alerts. It's an early telematics application that is already helping drivers save time and fuel, as well as cutting their CO2 emissions, because it helps them avoid fuel-wasting traffic congestion.

The real-time traffic data used by these systems can be collected from a variety of sources. These include cameras deployed along the road, sensors mounted on fleet vehicles (such as the entire AA Patrol fleet or National Express coaches in the UK), traffic helicopters or police radio dispatches. More recently, a method known as 'wireless signal extraction' has been developed to collect 'floating vehicle data' by capturing positioning information from the mobile phones carried by drivers and passengers.

Once the traffic data has been gathered, its transmission to the satnav-equipped car is generally done over an FM radio channel using RDS-TMC. This standard has been in use in several European countries (including in Italy for over a decade) to deliver traffic information to drivers, but is not expected to be robust enough to support the next generation of one-way, Web-based traffic information services.

"The industry is looking at using higher bandwidth channels, whether it's over digital radio, satellite radio, GPRS or 3G connections," says McClure. He believes that TPEG, a new wireless standard that allows for a more flexible way of encoding traffic information, will soon replace RDS-TMC.

The higher bandwidth afforded by TPEG should help address one of the main criticisms of RDS-TMC traffic data transmission. The latter system only covers motorways and, as a consequence, can lead to recommendations of secondary roads which might be just as - or even more - congested.

So far, Korea is the only country to have deployed a commercial TPEG service. Hyundai has recently started to sell vehicles with compatible navigation systems. TPEG trials are also taking place in North America, Australia and China, and McClure says he expects to see the first European systems within the next two years.

Greener air con

A UK research project called Sentience is currently testing a series of applications that could extend the 'electronic horizon' of cars by combining automotive systems with mobile telecommunications and advanced mapping software.

The best way to explain the concept of an 'electronic horizon' is with an example. Say your car is approaching a typical 90° corner in an urban environment with no traffic lights. At the moment, the only way to work out whether you'll need to negotiate the corner with another car is to wait until you have a clear view of the side road. In this case, you don't have an electronic horizon - your only 'horizon' is determined by how far you can see.

If both cars were equipped with interoperable telematics equipment, they could automatically alert each other about their presence a few metres before they reach the corner - expanding the drivers' 'horizons', or road awareness, electronically.

Such an application would require ubiquitous car-to-car communications, a technology that is at least ten years away. The Sentience project is concentrating instead on applications that could extend the electronic horizon of cars using existing technology at minimal cost. All tests are performed on a Ford Escape Hybrid.

Partly funded by innovITS, the UK centre of excellence for intelligent transport systems and sustainable mobility, the project has already obtained encouraging results in two applications relating to the environment.

The first one, called enhanced acceleration/deceleration (EAD), is meant to let drivers temporarily cede control of the accelerator and brake pedal to the car's computer so they can concentrate on steering. When EAD is in use, the speed of the vehicle is automatically and gradually adjusted to meet actual and virtual speed limits using an advanced form of adaptive cruise control.

GPS readings and advanced mapping data are used to calculate virtual speed limits by anticipating features such as bends, speed bumps, roundabouts and traffic lights. Unsurprisingly, the results have shown that the EAD system is on average 12 per cent more energy-efficient than human drivers.

The Sentience project has also tested enhanced air conditioning (EAC). Despite the increasing availability of eco-friendly stop-start systems - which cut a car's engine when it stops at red lights or traffic jams and restarts it as soon as the clutch is depressed - drivers often choose not to use them.

In many cases, this is because cutting the petrol engine will normally also cut the air conditioning compressor. "If you turn off the engine when the air-con is on, the temperature will fluctuate [upwards] by about seven degrees," says Tom Robinson, the Sentience project director and Ricardo UK's senior manager of control and electronics. "This is generally something that people are not comfortable with, so they often go for the non-economy mode."

The EAC application was tested using climatically controlled test facilities simulating typical UK summer conditions at the Ricardo Midlands Technical Centre. By linking the EAC, positional and powertrain control strategies, the system is able to anticipate when the engine is likely to stop, which enables it to generate a temperature buffer within the cabin.

"You've got a window of opportunity until the temperature starts to rise again where you're not running the engine and therefore saving fuel," Robinson explains. "It does take some fuel to get that pre-cooled temperature buffer in there, but the net saving is worth it."

In the Sentience hybrid test vehicle, fuel savings in excess of nine per cent were achieved for typical urban driving conditions.

Hyper-miling

So, you're back home after a tough day at work and your car is safely parked outside. Your navigation and telematics gadgetry has ensured you've driven as efficiently as possible, allowing you to relax safe in the knowledge that there's nothing else that you as a driver could have done for the environment. Or is there?

Last year, Fiat launched a green after-driving application called eco:Drive. Using the USB port of the Fiat 500 and Grande Punto, drivers can plug in a USB stick with a special programme in it that records driving patterns. Once back home, the data can be downloaded to a laptop or PC, where software co-developed by Fiat and Microsoft will analyse it, quantify fuel savings and CO2 emissions and suggest tips on how to become a more efficient driver.

 "There are a few initiatives like this. They're a little bit basic to start with, but you can be sure that's the direction the industry is looking," says McClure. "It's not strictly telematics because they don't download the information over a telecoms network. But I think that in future they will bridge that onto a telematics system. They've already got the basics built in the car to do that."

If you're wondering how much more eco-conscience might be needed before you can be bothered to spend your precious leisure time on after-driving applications, you should know that Japanese drivers love them.

"Japan is really where this is starting to take off," says McClure. "If you look at some of the systems offered by Nissan and Honda, people download this driving style information periodically from the car and then go to the [carmaker's] website. There, they have a ranking which compares their driving style to all of the other customers'. It's a kind of community-based incentive where people are trying to improve their ranking by driving more efficiently."

So how long until you're showing off your green driving ranking on Facebook?

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