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Fuel Efficiency Forum - Report
The first of EcoStation's Fuel Efficiency Forums was a great success, and proved to be a valuable knowledge sharing experience for all involved. Here is a summary of the topics discussed:
EcoStation's Fuel Efficiency Forum, 24th March 2011
The names of companies and individuals in this report have been removed to ensure openness in discussion within the forum itself. Of the companies present represent a wide variety of the freight task in Australia, including line haul, package delivery, bulk tankers, local pick-up and delivery, automobile transport, fuel transport, food transport and large transport companies with extensive distribution networks.
Alternative Fuels
BIO-DIESEL
A large scale Bio-Diesel trial involving over seventy heavy vehicles
A large fleet owned and operated by a nationwide groceries chain has been running a large scale bio-diesel trial on its Victorian fleet for the past three months. Their journey started with a small scale trial around five years ago with crop-based bio-diesel. Fuel sourcing was more difficult back then and there were public relations questions over the use of crop-based fuels.
The current trial uses bio- diesel from a country Victoria producer that produces the fuel from recycled animal and vegetable fats and oils. The trial started last year with six older trucks, to mitigate the risk potential harm to the vehicles. Monitoring was undertaken with data loggers, and driver feedback at was a mixture of "no different" and "slightly weaker under load".
The trial was scaled up to 100% of their fleet three months ago, with no hiccups in the conversion process. Of two fuel depots converted, one of them is undergoing maintenance and fuelling with regular diesel. The effect of this is that over time the trucks are being fuelled with B20 only half of the time, which means effectively the fleet is running 'B10'.
To this point (December 2010- March 2011), there have been no detrimental effects of bio-diesel on the truck engines (head carbonisation, etc.), and no related mechanical failures.
There were some implementation difficulties in finding a fuel supplier willing to mix the bio-diesel, but a solution was found by filling tankers to 80% with regular diesel, and filling the last 20% with straight bio-diesel at the producer. The fuel mixes during transit, and again when pumped into the depot tank.
The largest group of trucks in the trial are quite modern and from a European manufacturer that have years of bio-diesel experience. This manufacturer was very receptive to a long bio-diesel trial.
In operation, the bio-diesel fuel consumption rate appears to be lower (by volume and mass) than regular diesel on the group of trucks that were able to be benchmarked for fuel use before the beginning of the trial. One main test group of trucks using modern Euro 4 and Euro 5 engines has dropped from 42L/100km, to 40.1L/100km. This result is counter intuitive, as bio-diesel is typically listed as being a lower energy density fuel. In terms of calculated energy use per kilometre travelled, these trucks appear to be using in the region of 4% less fuel. These are encouraging numbers. Of the older trucks in the fleet (various manufacturers), with older Euro engine standards, a significant but slightly lower decrease in fuel consumption was also noticed. It should be noted that no additional driver training was undertaken.
With the better than expected fuel consumption to this point in their trial, the cost of the B20 added to the additional fuel transport and mixing leaves "no (additional) money in your pocket". That is to say there are small, but not significant savings if the truck runs 'OK'.
B20 Fits within the Australian Standards definition of diesel, which means the diesel tax rebate can be claimed on the entire fuel volume, without delineation between the regular and alternative components.
Of other companies to trial bio-diesel, one forum participant fills every 'fifth tank' with locally sourced bio-diesel, but doesn't consider that they get a fuel benefit.
CNG- COMPRESSED NATURAL GAS
An interstate line-haul operator's experience
One participating company trialled CNG in 1999 with a prime mover converted to run on 80% CNG and 20% diesel.
The conversion used an OEM dual fuel conversion kit, and one diesel tank was replaced with CNG pressure vessels. At the time the conversion costs were high at $74,000 and was supported by the Australian Greenhouse Office (this scheme no longer operates) and 50% of this cost was reclaimed.
During the trial three hundred thousand kilometres were travelled. While a 'huge saving in fuel' was seen, the trial was a considered a disaster in practice. The truck blew engines, gearboxes, differentials and the engine would de-rate and shut down. At the time, this technology was not proven for the running gear the truck was operating, and not for interstate running. The failures occurred when the CNG switched off.
It should be noted that this trial was conducted a long time ago and technology may have improved since then. Another participant operating bulk tankers tried a similar CNG trial at around the same time and ran into the same problems.
It was noted by others in the group that CNG runs very well on buses but struggles with heavier trucks. Another in the group looked seriously at a CNG trial, but the high capital cost of site fit-out was prohibitive.
LNG- LIQUIFIED NATURAL GAS
A bulk tanker metro fuel delivery trial
A participating company has trialled a fuel delivery truck running on LNG in Victoria.
The conversion to LNG for the truck itself was around $140,000 and as much as $700,000 in workshop capital costs. The system was fitted from a leading supplier of natural gas fuel systems for heavy vehicles.
In operation the amortised cost was around $1000 per month more than a diesel truck, when the price of diesel was around $1.00/litre. With the increasing cost of diesel to $1.40 per litre, the economics may now be line-ball, but the capital cost remains a drawback.
Reliability issues were experienced with engines de-rating, backfiring and generally less reliable. This is in part attributed to the LNG system switching off under light engine loading, which is a problem with vehicles that run heavy and get lighter as deliveries are made. Several people in the group recognised that the next generation of dedicated LNG engines will be much more reliable.
The main perceived hindrance to LNG implementation is the limited number of suppliers and re-fuelling options. In Victoria only a couple of options are available and the supply contracts are felt to be quite inflexible. Several in the group also noted that the suppliers of LNG have been talking about expanding the supply network for many years, but they are still waiting to see this happen.
Another current LNG drawback is the resale value of a truck fitted with LNG technology. This may be in part due to the fuel supply issues. "Nobody wants to buy a used LNG truck" was a statement that went unchallenged.
It was noted that another large transport company (not represented in this meeting) running LNG appears to be having great success.
A forum participant from a nationwide parcel delivery company has had an extensive report commissioned into LNG and CNG and are looking into it currently, though lack of infrastructure is considered an issue. Another participant is running one LNG truck currently in WA.
On the whole participants felt there was a good future for LNG, although at the moment the participants who have trialled LNG recognise no real financial benefits. There is some benefit with 'brownie points' from government (EEO), but more government support for capital cost is wanted. Upcoming alternative fuels tax policy changes may negatively impact or slow implementation.
Tyres
LOW ROLLING RESISTANCE TYRES
A trial on both metropolitan delivery, and interstate line haul
Low rolling resistance tyres have been trialled for both metropolitan and line-haul use by a bulk tanker company with differing results. The tyres used were from a European manufacturer and were compared to standard tyres from the same manufacturer. The cost of the low rolling resistance tyres was 10-15% more than standard.
For line-haul testing, a truck trailer combination gave a 2 to 2.4% decrease in fuel use with a good, consistent driver. They are satisfied that in this application the tyres did make an appreciable fuel saving. In this application the drive tyres lasted 204,000km, as opposed to the standard drive tyres that are still going after 300,000km. From their experience these tyres are reported to be cost neutral, or slightly cost negative in line-haul operation.
In metro applications this company found no detectable fuel savings and a greatly increased wear rate. The application of the trucks using these tyres involved a lot of low-speed tight radius tyre scrubbing when manoeuvring around metropolitan fuel depots. As well as high wear rates, abnormal wear (scalloping) was particularly evident on trailers.
Another participant representing a company that drives both on and off road is looking into low rolling resistance tyres and reported manufacturers claims of a WA company (not represented at the meeting) that have seen a 3.4% decrease in fuel usage from low rolling resistance drive tyres alone, and predict 5% if used on the whole vehicle. No additional information was available. This tyre manufacturer only supported line-haul application for these tyres.
Mixing low rolling resistance tyres with standard tyres on different axles may reduce fuel savings as the total drag effect will be cumulative over all axles. This could address abnormal wear issues on some higher-scrubbing axles. Some manufacturers insisted on front to back use of the tyres.
Another large freight company is trialling low rolling resistance tyres in QLD, but no results are available yet.
Participants among the group with low rolling resistance tyre experience generally agreed that there may be in-service fuel savings and positive environmental results in line haul applications, but metro and farm/ off road use were not recommended. There was little in the way of cost savings in line-haul, and negative cost effects in metro. Managing tyre inflation properly was suggested as a higher priority for fuel efficiency.
CENTRAL TYRE INFLATION SYSTEMS (CTI), AND TYRE INFLATION MANAGEMENT
Using CTI systems as a fuel saving device was raised. CTI is commonly use on logging trucks to allow lower pressure settings off road. CTI can reduce instances of truck getting bogged in winter but is not necessarily a fuel saving technology off road. One company with a farm pick-up task reports two trucks per month bogged in winter, and they no longer allow farmers to pull trucks out for safety reasons (chains/ shackles are not rated, etc).
Some concern was expressed over driver input and driver override of multiple- setting CTI systems. Some drivers apparently lower tyre pressure for greater ride comfort, and installing a system that allows this could be a safety and fuel efficiency concern. Drivers also need to be aware that these systems can have a 5-6 minute inflation time (from off-road to bitumen pressure), and during this time tyres could generate high temperatures from increased sidewall flexing and scrub. There is also the possibility of drivers forgetting or not bothering to re-inflate tyres. Systems that maintain a set pressure and have no driver interaction are also available.
A figure was given a $7000 for a CTI unit was given by a participant who has recently looked into it as a retrofit, and approximately half that cost with OEM fitment. Several trailer manufacturers offer these systems.
Tyre inflation checks as routine maintenance (not a technology upgrade) was discussed with the issue of less than adequate checking being raised. One company found during tyre inflation audits that some regions were much better than others, and some tyres were as much as 20% underinflated. Access to valves for inner wheels was a concern, as was the training level of the employees of tyre workshops (poor fitment issues also raised).
Driver Behaviour
DRIVER TRAINING
A large parcel delivery company's experience
Eighteen months ago this company began a trial program, primarily focussed on defensive driving.
Key measurement parameters of the training included harsh braking, over-revving, and time spent in the engines 'sweet spot'. Three groups of ten drivers were picked at random and a six month baseline measurement of the key parameters was undertaken. Data was electronically recorded via a GPS 'black-box' system configured for driver assessment. The trial was conducted for three months.
Three different training approaches were trialled to assess the effectiveness of each approach. These were:
1. 'Traditional' training via regular toolbox talks to drivers 2. A blended approach with some e-learning, and some in-truck instruction 3. E-learning, online training
The results of the trial varied depending on the type of driving. As expected, Line haul yielded little improvement, due to the relatively long time spent at constant load. Also, these line haul drivers were already 'high achieves' among the company's drivers.
For the blended training approach, a fuel efficiency improvement of 1.0% resulted. Interestingly, the best result was recorded for the e-learning approach with a 6.6% improvement. Fuel reduction was achieved by a combination of all driver program elements; i.e; sweet spot improvement of 14.4%, idling reduction 40.4% etc.
A bulk tanker farm- pickup company's experience with driver training and performance incentives
One participating company has trialled a large scale driver fuel efficiency program in Tasmania among sixty five drivers. This scheme involved fuel efficiency performance targets that gave the drivers a 0.5% pay rise per annum, written into their EBA, for three years if the 5% fuel target was achieved. The driver's pay rise rewards were capped, so that additional fuel savings over the targets were a benefit to the company alone.
The program was reportedly very successful, with the drivers hitting their three year target in a matter of only three months! Although the program was controversial at first among drivers, and EBA negotiations took time, those involved now consider it a good outcome.
Each of trucks had three drivers and fuel was monitored on a per truck basis. Training was undertaken with a combination of trainers, some provided by a truck manufacturer, and twenty drivers did in-cab assessments. In all, 50-80% of drivers engaged strongly with the program and took it seriously. Some drivers have begun recording their own fuel consumptions and are competitive with each other for the best results. Driver assessment at this company now includes 'driving of fuel'.
The success of the Tasmania trial has lead to the same program being implemented in Victoria. This is in early stages, but the fuel saving figures are looking very positive.
As well as hitting performance targets very early, this trial highlighted some important safety issues surrounding fuel efficient driving that had to be addressed. Some issues include:
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The training also highlighted the fact that many drivers did not realise there were different settings for the engine retarders, and generally helped them in better understanding the available features of their truck.
An interesting point was that one driver from one company drove at unsustainably low speeds with very slow acceleration and deceleration for several days as an experiment in finding how much fuel could be saved for his runs. This yielded a 20% improvement.
LOWERING SPEED
The issue of lowering the cruising speed of trucks to save fuel is well known to most participants and reducing aero drag is recognised as a major area for improvement on vehicles for high speed applications. Although significant fuel efficiency improvements have been experienced by carriers, several issues were raised around this point.
One participant with a large line haul fleet stated that around a 10% fuel saving can be achieved by lowering speed for 100 to 90kph. Another company tried reducing speed from 100 to 90kph and recorded a 4-5% efficiency improvement, but increased speed again for safety reasons. They have also found a 2-3% saving by reducing cruising speed from 103 to 100 kph.
An interesting point from another large bulk tanker operator was that a speed reduction on similar trucks with identical engines gave very different results depending on final drive (differential) gear ratios. Their trucks with 'high speed' diffs (lower engine speed in a given gear per road speed) prevented fuel savings when the cruising speed was reduced. Their trucks with standard diff ratios gave a 5-6% saving when speed was reduced. This difference correlated to results from the company's driver training simulator (a $500,000 dollar investment they have made in driver training). This highlights the importance of correct gearing for the task to keep the engine closer to its optimal load/ efficiency point. It was suggested by another in the group that the high speed diff with a higher powered engine could give a fuel reduction. It is clear that more investigation in this area is desirable.
The safety aspects of lowering speed is related to what it compels other road users to do to pass the truck. Participants reported 'trucks being run off the road' and mention was made of routes where lower speeds were very dangerous due to road infrastructure, such as Melbourne to Adelaide. A participant noted that they had drivers lowering speed on their own initiative on sections of road where they deemed it 'safe'.
OTHER DRIVER RELATED ISSUES
Driver training simulator
One participating company is training drivers for efficiency and have experience up to 10% fuel savings in some cases. So far, thirty drivers have been through their simulator and it is too early to tell whether the $500,000 investment will pay off. The training results (simulator based) suggest that an efficiency gain of 6% could be taken onto the road. Some skilled drivers show little benefit through simulator training as they are 'near perfect' already, but many experienced drivers still make large gains. Keeping the engine in the right operating range, particularly on acceleration is a large area for improvement with the simulator showing that skip shifting has no gains and progressive shifts are better.
The simulator has apparently been very valuable in communicating with the drivers and showing them results that relate directly to torque charts. Another participant involved with driver training has had difficulty in getting drivers to understand torque charts, but said the simpler 'green band' (tachometer range) was instead a focus. This suggests that simulator training may be useful in developing the driver's level of understanding of where and when energy is used in the truck.
Automatic gear changing
Automatic gearboxes were briefly discussed in relation to fuel burn, and some agreed that an auto box will 'bring bad drivers up', but can make very good drivers slightly worse. Some claimed no benefit from automated gearboxes, but one participant disputed this and have found gains, particularly when operated in manual mode to anticipate terrain changes
Driver recognition
Recognition for drivers was regarded by all as being very important. Participants knew of companies who had never really talked to their drivers at all. A financial incentive for drivers was generally regarded as important and most supported this. Some drivers will learn and change on their own, but the participants agree that 'rewards change attitudes'.
