Just ahead of Earth Day, which happens to be this April 22, Lenovo has announced a new series of ThinkPad laptops it touts as "the greenest on the market" for their use of post consumer recycled content. Targeted at business, government and education customers, the new ThinkPad L412 and L512 laptops feature the latest Intel Core processors as well as a full range of connectivity options from Ethernet and Bluetooth to Wi-Fi, 3G and 4G.

Spec-wise there is nothing too special about the new series. It will start as low as $649 and offer a modest range of customization options, running from as little as a 1.86GHz Celeron and Intel graphics to a 2.53GHz Core i5 and a dedicated Mobility Radeon HD 5145. Perhaps more interestingly, Lenovo claims the 14-inch L412 and 15-inch L512 laptops "meet eight different military specification tests for high and low temperatures, vibration, altitude, dust, and more."

Likely due to their ruggedness they are a bit on the heavy side, starting at 5.2 pounds. Other features include up to 8GB DDR3 RAM and 500GB worth of storage, four USB ports, a 7-in-1 card reader, support for DisplayPort, and a listed eight hours of battery life with a 6-cell battery. On the environmentally-friendly front, the laptops are said to use up to 30% post-consumer content from office water jugs and used IT equipment in parts like the LCD case, palm rests and outer cover. Overall, the 15-inch L512 contains 18% post consumer content, which Lenovo says is the highest in the industry.