German researchers have considered the ancient science and art of plowing, and have come up with a novel solution to reduce its environmental impact: Coating the metal blades of a plowshare with diamond-like carbon.

Diamond-coating is something you're probably familiar with as a high-tech solution to making super sharp, long-lived cutting edges. The breakthrough achieved in the German Fraunhofer Institute has been to use diamond-like coatings instead (DLC). DLC is structurally similar to diamond, meaning it shares some of that material's famous resilience and strength, but it's actually possible to fix it to all sorts of different materials in all sorts of shapes--making it extremely useful as a protective coating in high-stress bearings, where it makes the joint long-lived, and in devices like hard disks, where it protects the surface of the magnetic platter from impact damage.

Plowing is all about friction: The stresses involved in dragging a plow full of large metal blades through many-inches-deep soil--laden with stones and roots--are so evident that don't need a degree in physics to realize how hard a task it is. The German researchers suggest about 50% of the energy put into the plowing process is instantly wasted in overcoming friction, and this accounts for a significant portion of the million liters of fuel the German farming industry uses up each year in working the land.

Hence the new attempt to coat the blades with DLC. This instantly reduces the plow's friction by 50%, and can actually reduce the energy required from a tractor hauling the coated plow by over 30% compared to an uncoated plow.

There are instant payoffs from this innovation, but there are also a lot of secondary ones. Larger farms will consider the fact that with reduced friction, a plow could be made much wider and still require the same tractor power, which could have significant time and fuel pay-offs on large fields. On the other hand, using the same size plow now needs a less powerful tractor, which also translates to fuel payoffs. Meanwhile, since it's easier to pull a plow now, there's less wear and tear on the tractor, and the plow blades themselves last much longer.

Considering the simplicity with which this technology could be exploited, and the considerable environmental benefits it could result in, there's an extra poignancy in reusing the phrase "turning a sword into a plowshare," since DLC can be used to make weapons much stronger, as well, though for much less benefit than when used on plows.