AdBlue is not a solution

Posted: Sun 20th November 2016 in Blog

What happened to the KISS principal? Keep It Simple Stupid. I have recently discovered the indescribably poor solution to the problem that is Diesel Exhaust Fluid also known as AdBlue. To be honest it does make the Volkswagen emission scandal make more sense.

If you didn't know AdBlue is a chemical that is sprayed into the exhausts of some modern Diesel engines to clean up the emissions, a bit. It can't be the best solution to the problem? I know diesel exhaust, particularly in towns is a major problem. Even one of the tractors out here has it. let me explain:

A normal modern engine (diesel or petrol) has fuel tank, a pump to pressurise fuel, injectors and a computer. The pump insures a constant supply of hi pressure fuel to the injectors, which are basically solenoid valves with a nozzle on the end. A modern diesel engine has 2 of each of these. One to introduce fuel to the engine, and another tank, gauge, filler, pump, computer, injector to squirt AdBlue into the exhaust. That's doubled the complexity of the fuel system.

Then they'res supply, you have to buy AdBlue, and fill it up, some manufacturers have put tank in that they hope will carry you between services, then you get changed hundreds of dollars to fill it up at service. Either that or you have to do it you self, and yes it costs money, quite a bit of money.

This being an environmental thing its justified? Right? Hmm, I have some suspicions on that. It will have to perform an environmental miracle to actually break even. The AdBlue is shipped in cartons, not with Diesel in a tanker, so that's another delivery journey, out here it turns up in 10l cans complete with pourer nozzle. That's a lot of plastic, plus another journey. Its generally said more than 50% of a cars emissions are in its production, adding a complete extra system to inject AdBlue into the exhaust is more energy consumed in production. The life of a car is (mostly) a function of the cost of repair, usually its not that something can't be fixed, its that its not financially worth fixing it. Imagine in 15 years time your AdBlue goes wrong, its a fairly complex system, therefore expensive to fix. Should it give out in an older car it will kill the car in the "not worth repairing" sense.

So yes it cleans up the exhaust, but does it do it enough to off set all the above, Tim had to get some for the tractor, so he drove to town 120Km round trip (in an old mechanical injection diesel landcrusier) to get plastic bottles of AdBlue to clean up the emissions of a tractor. Then we had to fill the tractor, so it productivity terms its a bloody disaster. That's all without taking into account the environmental impact of its production, about which I know nothing. 

I see a legislation feedback loop here, this design doesn't show elegance, practicality or tangible benefits to the car (or tractor) owner. Its environmental impact, taken holistically appears pretty weak at best. I understand VW's decision to cheat on tests, apparently the "fix" for the VW emissions scandle is to fit AdBlue systems to their cars. I do sympathise more with VW, they must have been desperate to avoid this solution to the problem of Diesel Emissions.

Since I wrote this offline I've done more research, it appears to remove 99% of NOX emissions, which is significant. Still, its labour intensive, expensive, complicated and annoying.