5 Green NASA Inventions

Researchers at NASA didn't invent solar cells, but the organization did help keep the technology alive during the years when it was still largely uneconomical. Solar power has long been of interest at NASA, starting with Vanguard 1, the first artificial satellite powered by solar cells to start circling the globe. It launched in 1958, just four years after the first modern solar cell debuted, although it fell silent by 1964.

General interest in solar power waned after the energy crisis in the 1970s, but NASA was still a paying customer, pushing for the development of more efficient and affordable solar cells. Among the many spinoff products that came from these ongoing research efforts were solar-powered refrigerators, solar-powered air conditioners, long-lasting and low-energy lighting options, solar-powered air monitoring systems and solar-powered hot water heaters.

When NASA was looking for ways to make sure the Apollo spacecraft and space suits were habitable for astronauts, it started experimenting in the field of insulation. Both the fierce cold of space and the heat generated upon re-entry would prove deadly if the astronauts were unprotected, and one example of an application that emerged from this need was the Apollo command module's radiant heat shield.

Advances in insulation helped raise awareness about radiant barriers and other improved insulation methods, which resulted in spinoff products that are used in all sorts of applications today. One example can be found in construction. Many residential and commercial buildings erected over the past decade and a half include insulation that was developed following NASA's lead. Superior insulation helps save on energy costs and is one of the cornerstones of the Energy Star's qualification requirements for building certification.

NASA astronauts need continual supplies of freshwater, so it should come as no surprise that the work of NASA researchers has frequently focused on water filtration methods. In fact, one of the Space Technology Hall of Fame inductees admitted in 1988 -- the first year the honor was offered -- went to ongoing research in this field.

Researchers in the 1970s and '80s discovered and developed water filtration techniques that took advantage of unique traits possessed by water hyacinths. While in most cases water hyacinths are considered to be an invasive species, the plants have also shown great potential in the field of wastewater treatment.

Conventional water treatment plants require expensive equipment and valuable energy to run, but treatment plants using water hyacinths require little of either. The hyacinths need no artificial heating and little aeration; they can survive in heavily polluted wastewater with no problem; and they grow at exceedingly rapid rates. It works because the hyacinths have a mutualistic relationship with certain bacteria that live on their many root hairs. The bacteria break down waste and turn it into nutrients the plants can digest. The hyacinths are also excellent at removing heavy metals and toxic chemicals from the water that other treatment methods aren't effective against, so the end result is incredibly clean.

This might seem odd considering how much of NASA researchers' focus is directed skyward, but from time to time, they also study how to improve soil conditions right here on Earth. (Though to be fair, the main motivation behind at least one important innovation was cleaning up contamination that NASA caused in the first place.)

During the Apollo program, NASA workers used toxic chemical solvents to clean the rockets waiting on the launch pad. These solvents are also employed in manufacturing processes as diverse as producing dry cleaning fluids or keeping pests away from growing crops. Unfortunately, when released into the ground, they spread far, last a long time, and when they eventually do degrade, they often produce other harmful substances.

So scientists from the Kennedy Space Center teamed up with researchers from the University of Central Florida, and together they developed a way to remediate the solvents that was faster and more cost-effective than the few existing methods. The resulting process won the NASA's 2005 Invention of the Year award in both the government and the commercial category. It works by using tiny particles of emulsified zero-valent iron (or EZVI) suspended in water droplets which, in turn, are emulsified in vegetable oil. The iron triggers a chemical reaction which reduces the level of solvents; then the hydrogen that's released when the vegetable oil ferments further decreases the amount of environmental contaminants in the soil.

Work at NASA has focused heavily on hydroponics for many years, since plants are considered crucial for the hopes of prolonged spaceflight. Flourishing plants would aid astronauts in many critical processes such as food production, oxygen release and waste recycling. Hydroponic systems have traditionally been complex, however, so NASA researchers started looking for a substrate that would eliminate many of those hassles. This led them to explore an option known as zeolites, which are naturally occurring minerals with honeycomb structures that can be modified to house essential nutrients until plants are ready to consume them.

This development in slow-release fertilization is now being applied commercially in places like golf courses and playing fields. Zeoponic products are better at delivering nutrients to plants, so much less is lost to surrounding soil and groundwater. Plants also thrive more when zeolites are present, so plant biomass production goes up.

Learn more about other green technologies on the next page.