Diesel engines aren't going away, and something such as mentioned in this article is desperately needed. As mentioned by LouNY and others, the effort to "clean up" diesel emissions has been wrought with foolishness, trading reduced NOX and soot for higher CO2 emissions, plus adding appreciable mechanical complications and chances for something to go wrong. I have always felt DPF's are particularly foolish for tractors. NOX and soot are a particular pollution problem in high traffic areas like cities where it is the major contributor to smog. It is not really that much of a concern in rural areas where most tractors are used. CO2 emissions are a problem everywhere, regardless of where the are created.
When I visited a friend in Holland a couple years back, he explained how the Dutch and several other European governments had a little trick to minimize the localized pollution effects of gas vs diesel engine use. The initial purchase price for a diesel powered vehicle is taxed high, but the fuel is taxed low. On gasoline vehicles, it is the opposite. Purchase price is taxed low and fuel is taxed high. The net result is that for people who drive few miles (city dwellers) it is more affordable to use cars with gas engines that put out less NOX and soot where it really causes problems. However if you drive a lot of miles, it is more considerably more affordable to drive a diesel in the long run, which has lower CO2 emissions, but pollutes with soot and NOX out on the open road where it is less of a problem. The strategy works and is viewed as a measurable success in managing pollution.
For those who have never had problems with DPF's, bully for you. I am certainly not in that group. I have had two failures on my Mercedes diesel motor home and two nearly $1,000 tow jobs due to DPF clogs. I sold that otherwise great motor home because of that re-occurring problem.
