It is rare that I mention green and cars in a positive light given the huge amount of emissions private vehicles produce--and the planet-damaging sprawl the overplanning for them engenders--but in the case I will make the rare exception and praise.
That goes to Japanese-owned carmaker Subaru. Not because it is a leader in bleeding-edge technology like hybrids, or that it makes tiny gas-miserly vehicles like its larger competitors, though its vehicles are very fuel efficient through using advanced proven technology.
Instead Subaru gets the accolade because they have built a low-environmental-footprint plant in Indiana that it is proudly advertising on TV that is a far cry from the creaking and wheezing factories belonging to the dying Big 3. And because their cars and compact SUVs, such as the popular Outbacks and Foresters are so well made they last near-forever (300K-400K is not uncommon)--which means less resources needed to build new and to repair existing ones.
Long-lasting vehicles are an environmental virtue. Anyone who has worked at or toured a car factory or for that matter a steel mill or aluminum plant knows and can appreciate just how much energy: electricity, coal/coke that goes into making vehicles and sees and senses the resulting pollutants from the entire auto-building process. That also goes for the trains and trucks that haul the materials, finished products to the dealers, and the vehicles back for scrapping.
The Subaru dealerships are truly dedicated to keeping the vehicles going as are their owners. Their higher-than-average pricetags encourages you to do just that. Then again, a used Subaru beats most other similar new vehicles hands down in reliability, longevity, and ROI.
There's also another benefit: fanatical customer loyalty. Subarus have 'built-in CRM'. Once you own one you never want to drive another make.
I can testify to the above. I own a secondhand 2001 Subaru Forester that I've driven everywhere from Vancouver Island logging roads to equally cratered Staten Island residential streets, swerving around both bears and bearish pedestrians with ease. It has just over 150,000 miles, which means it has easily 150,000 or more to go. The all-wheel-drive makes even New York City parking a no-brainer and takes the edge off coping with icy hilly roads like through the Poconos in Pennsylvania. It isn't coincidence that Vermont and New Hampshire have long been Subaru country.
The key to keeping Subarus or any other vehicle truly green is minimizing the mileage-killing start-and-stop commuting trips as well as regular maintenance including tune-ups. I work from home and when I have to travel to a large city or airport I take the bus, train, or park-and-ride at a commuter rail station. This also keeps my rolling investment free of damage, thereby extending its lifespan and value.