ETC Green runs the Common Rail Diesel engine powered Jeep Grand Cherokee for our survey vehicles. We use biodiesel blends in the Jeeps (up to B50) and are happy with the typical 52 MPPG (Miles Per Petroleum Gallon) performance. This is a photo of one of the Jeep’s dashboards on a ~400 mile trip – pretty typical for highway driving. Since we use B50, this represents 52 MPPG.
So while these Jeeps are full-sized, AWD SUV’s, with as much torque as a Corvette and the towing capacity of a full-sized truck, our fuel performance exceeds the MPPG rating of what the media has labeled “Green” cars such as the Prius, Insight, Fusion, Volt, etc..
Everyone today seems so focused on MPG, yet this unit of measure is outdated. If the fuel is sustainable, economically viable and environmentally friendly, then MPG is not that important. Actually, if vehicles were running on B100 sourced from 2nd generation feedstock, then lower MPG is more desirable as it better supports our economy. ETC Green Engineers are working with the EPA and DOT to establish a new unit of measure – MPPG (Miles Per Petroleum Gallon) so people have a better understanding of the performance and emissions of the vehicle. For more information please review the article, Are you driving your last gasoline powered car?
Petroleum is a finite resource. Doubling the MPPG for vehicles is wrong headed in that this direction only delays the depletion of this finite resource. Emissions from any vehicle running on petroleum sourced fuels – including gasoline powered hybrids such as the Prius and Volt – have no life-cycle emissions off-sets. As compared to petrodiesel, biodiesel has radically reduced emissions: use of preferred sourced B100 completely eliminates lifecycle carbon dioxide emissions (CO2), it also reduces emission of particulate matter by 40-65%, unburned hydrocarbons by 68%, carbon monoxide by 44-50%, sulfates by 100%, polycyclic aromatic hydrocarbons (PAHs) by 80%, and the carcinogenic nitrated PAHs by 90% on an average. There are a list of proven biodiesel additives off-the-shelf that virtually eliminate NOx emissions. The biodiesel molecules are simple hydrocarbon chains free of the aromatic substances and sulfur associated with fossil fuels.
Since the current business plans for large scale 2nd generation feedstock in the US include the planting of 10 billion 12′-14′ tall trees, this solution can also claim the air filtration benefits of those trees including the reduction of heavy metals from coal burning power plants and various particulates from petroleum burning vehicles.
Our Jeeps’ Record High MPPG:
Our surveys take us into the “Outback” of Nevada, California, Arizona and Utah on a regular basis. We were recently returning from a site survey when we pulled into an isolated station to discover they only sold 100% petroleum based diesel. We calculated it was about a 60 mile drive along our return route to a service station known to sell a biodiesel blend (there are 120 in the southern Nevada area). While our fuel level was low, we calculated that we could make the distance. It was already past 6pm and there was virtually no traffic on the rural highway so we set the cruise control at 55mph to reduce fuel consumption though the speed limit was 70mph.
We would rather be driving a smaller, more fuel efficient vehicle all the time, but it is not uncommon for us to haul around over a ton of survey equipment, we often have to go off-road and we pull trailers with wind turbines and other heavy equipment. We have verified the Jeep’s on-board computer for accuracy in the past, but we did again that day because when we pulled up to the biodiesel pump we were looking at an additional 64 miles on the odometer and an average of 64 MPPG in an AWD, 215HP/376lb-torque, full-sized SUV.
Cold Weather, Diesel Engines and Biodiesel Fuel:
We have read a great deal about cold weather problems with biodiesel blends. In the first month we owned one of these Jeep’s, we looked for the coldest weather in the region and made a road trip. We were using B10 per the manufacturer’s recommendation (we have since increased to B50 based on our research and fluids analysis). This vehicle’s Daimler BlueTec diesel engine includes a fuel line heater.
The first night it dropped to -18 degrees F with a wind chill of -28 degrees F. The next morning, we brushed the 14″ of snow off the Jeep and rolled down the windows so we could hear the engine turn over (seriously, this Jeep is so quiet, you can’t hear it start with the windows rolled up). The engine fired instantly – no whining, no hesitation to start – also for those people who have not driven a vehicle with a CRD engine, there is no delay for a glow plug – just instant starting as in any gasoline powered car.
The next morning it was -22 F with a -34 F wind chill. There was another 21″ of snow on the jeep and it started up just as it had the previous morning. We’ll have to look around to find temperatures in our area below -34 F, but this temperature covers at least 70% of the contiguous US states and probably 90+% of the population. With CRD/TDI engines that include fuel line heaters, cold starting should not be a problem with B10. There are cold weather additives that can make biodiesel blends and even B100 viable to -40 F.
Update 2010-02: We have since tested our own biodiesel in a B50 blend to -20 F with no issues. If people and fleets are having problems with biodiesel blends it is because the biodiesel production facility is being negligent in adding the cold weather additives and/or the vehicle does not have a fuel line heater. Both of these issues are easily and rather inexpensively corrected. Now when we hear of cold weather issues on diesel engines, we try to educate not only the vehicle owner, but we contact the biodiesel production facility and try to persuade them to raise their level of customer commitment. We have to work together to eliminate all these out dated biodiesel stigmas.
Long Trips while Towing:
Update 2010-11: We now have 46,000 miles on one of our Jeep’s and that vehicle just completed a 3,700 mile trip to northern WI to pick up a load of solar thermal panels for a project. The Jeep was driven at the speed limit towing a 1,200lb 10’x5′ enclosed trailer with a ~3,000lb load ~4,200lb total. There was one steep mountain where the Jeep kicked down one gear for a few seconds, but otherwise it pulled the trailer effortlessly. The max tow for this vehicle is 7,500lbs. With the high speed towing, our MPPG dropped to 34-38, but this was to be expected.
Update 2012-04: We now have over 87,000 miles on one of our Jeep’s and that vehicle just completed a 1,700 mile trip to Salt Lake City, UT to pick up a trailer load. The total weight of the trailer and cargo was 4,500lbs and we cruised at about 70mph on the return trip. The Jeep performed extremely well averaging about 36MPPG on the return trip. The use of biodiesel blends keeps diesel engines very clean compared to the carbon deposits that are associated with petroleum only sourced diesel fuels. This vehicle has had (full synthetic) oil changes (oil and air filters are changed with every oil change) at about 10,000 mile intervals and we replaced the fuel filter at 40,000 and 80,000 miles. The only other repair this vehicle has required was after 2 blow-outs within an hour in the outback of AZ, we ran on a flat tire for 10 miles (economic decision per Staff count in the vehicle) and damaged the PSI sending unit inside the rim. The rim was undamaged and still in-use on the Jeep. Jeeps are tough in general – with a diesel engine – they are unstoppable – we intend to drive these vehicles past 500,000 miles.