Gredig: New emission control technology

It may not be top of mind for farmers, but for the farm equipment sector, meeting ever tightening emission standards for diesel engines has been a major challenge. AGCO’s approach to meeting Tier III emissions standards was revealed to ag media and producers recently when the company unveiled their new high horsepower (205 to 275 PTO hp) row crop tractors from the Challenger, AGCO and Massey Ferguson lines.

 

Whether you are in the market for a new tractor or not, eventually everyone is going to need to understand how these emission technologies work and what they mean for owner/operators of new diesel powered machines, including trucks.

 

To understand AGCO’s direction on the emissions issue, there are some new acronyms to learn – SCR and DEF for starters. SCR stands for Selective Catalytic Reduction, a technology already in use in Europe. To dig deeper, you can go to www.factsaboutscr.com, but the general idea is to utilize engine technologies that maximize power and fuel efficiency, and deal with emissions as they leave the engine. The primary targets on the emissions side are nitrogen oxide (NOx) and particulate matter, which is essentially soot.

 

The alternative to SCR is to employ advanced Exhaust Gas Recirculation, or EGR systems that deal with emissions by sending exhaust gases back through the engine. While it appears that the bulk of the trucking and ag sector will utilize SCR, there are players that are going to stick with EGR. According to AGCO, the Sisu engines used in the new tractors produce more power while providing up to 15 percent better fuel efficiency than engines that utilize an EGR system.

 

SCR technology is not new and it’s not just for agriculture. According to David Uschwald of  Daimler, there are hundreds of thousands of diesel vehicles utilizing SCR systems in Europe, and transport truck manufacturers in North America are headed in the same direction. SCR equipped engines utilize a liquid product called DEF, which stands for Diesel Emission Fluid. This is a product that tractor and diesel truck owners across North America will soon be familiar with.

 

Here’s how it works: A diesel tractor or truck that utilizes SCR will have both a diesel fuel tank and a smaller tank for DEF. DEF is not a complicated product. It is made up of two thirds ionized water and one third urea – it is a stable and non-toxic liquid. Each of the new AGCO tractors has an 8 gallon DEF tank that is located close to the main fuel tank for easy access and filling. AGCO says that DEF is used at about 3 percent of diesel consumption, so for every 100 gallons of diesel, you’ll need about 3 gallons of DEF. One fill-up of DEF will last 2 full fuel top-ups.

 

 

 

As the engine warms up, the DEF is injected at the appropriate rate into a catalyst chamber where it encounters exhaust gases. When heated, the urea in the DEF turns to ammonia and reacts with nitrogen oxides in the exhaust, converting the pollutants into nitrogen, water vapor and carbon dioxide. AGCO claims that the technology can achieve nitrous oxide reductions in excess of 90 percent. Particulate matter levels are also reduced through this process.

 

Uschwald has been working to prepare the North American trucking industry for the arrival of SCR diesel technology for the past year or two, and it’s a big job. Every truck stop across North America will have to have DEF available to accommodate new SCR equipped trucks. For farmers, Uschwald sees a simpler transition as producers will be able to simply buy 2.5 gallon (10 liter) jugs of DEF as required. Uschwald says that it won’t be long before bulk containers of DEF with self-contained pumps will be available from fuel suppliers. When the container is empty, the supplier will drop off a full one and pick up the empty.

 

There are some issues that must be acknowledged. DEF is prone to freeze at temperatures below 18 degrees Fahrenheit (- 8 degrees Celsius), so bulk storage must be kept warm during the winter. Also, you won’t want to run out of DEF while in the field. The new tractors from AGCO are programmed so that if you run out of DEF, the tractor will automatically reduce power output by 50 percent, allowing you to get home, but field work will not be possible.

 

For AGCO’s new tractors, the SCN system is branded as e3 which stands for energy, economy and ecology. Click here to view a short video from Jason Hoult, AGCO’s manager of high horsepower wheeled tractors. Farms.com met with Jason at the Louisville National Farm Machinery Show. He describes the e3 system now available on the new Massey Ferguson 8600 series tractors.

 

What do you think of the different technologies being used by equipment manufacturers to address emissions? Will the use of SCR versus EGR technology influence your buying decisions?

 

Click here to join the discussion.

 

Peter Gredig

Farms.com