Technology Grows on Trees

By: Jessica Robertson

A newly discovered process can turn trees into energy storage devices, essentially. Cellulose, the most common organic polymer on earth, is the main ingredient in trees. And when cellulose is reacted simply with ammonia, it can be transformed into a form of activated carbon, called a nitrogen-doped nanoporous carbon membrane, that can serve as the electrode of a supercapacitor. 

Besides the simplicity and cost-efficiency of this new approach, the process is also impressive in its earth-friendliness. The only byproduct of the reaction is methane, which, when properly harnessed and not released into the atmosphere, is a safe and advantageous compound, useful for fuel or other industrial purposes. Furthermore, the cheap wood that can be used as the reactant in this approach does not deplete the food supply. The carbon membranes that are produced in this reaction are extremely thin, meaning a small amount of wood creates a large number of the desired supercapacitors, dispelling fears that the process would deplete the forests for the sake of energy.

Supercapacitors are highly efficient energy storage devices, recharging faster than batteries and holding much more energy. They promise better results in industry and electronics, and they could be the solution for evening out the power flow from variable alternative energy systems like solar and wind energies. They increase efficiency in hybrid cars, and prevent energy loss by capturing what would otherwise be wasted. These potential benefits of supercapacitors have been known for some time, but the high cost of such technology prevented any substantial incorporation of their strengths into many industries. This new, low cost process to create supercapacitors has the potential to shift significantly the environmental impact of modern industry. 

She Sells Seashells (and Energy?) by the Seashore

By: Jessica Robertson

The power of the ocean is undeniable. With new technology, that power could be harnessed in such a way that seashells and seafood won’t be our greatest export from the watery giant for much longer.

Renewable energy falls into the top-priority category among global sustainability issues; the more avenues we have for garnering clean, renewable energy, the better for our planet. The ocean is full of frighteningly powerful, high-energy water, and turning that power into electricity would be emission-free, and genius. Good thing the plans, though in their infancy, are underway!

Some of the biggest names in the energy industry are teaming up to turn these ideas into reality. Lockheed Martin, Scottish PowerRenewables, MeyGen, UC Berkeley, and the US Navy are just a few of the familiar names on these impressive projects. Five types of power-generating machines are under testing, either in the lab or in the open seas, currently.

Two of the projects, particularly, are standouts. The largest wave energy project, already in the water off the coasts of Australia, consists of special buoys anchored to the ocean floor; as waves roll, the buoy moves with the wave and the anchor stays intact, causing the tension to power a hydraulic pump. The energy moves through wires to the coast, where it is stored; one single buoy’s energy can power an astounding maximum of 10,000 homes. While that number is staggering, the most effective prototype, it seems, is known as the magic carpet. Intended to be placed off the coast of California, on the sea floor, the giant mats absorb the energy that is normally dissipated into the sand on the bottom of the ocean. Careful placement of the mats, avoiding coral reefs and other marine habitats, could also create “safe zones” to protect harbors during wild storms and prevent erosion due to their ability to absorb up to 90% of waves’ energy.  Just a one square-meter patch of the mat creates enough power for two homes. Open-ocean trials are scheduled to begin in April 2016.

One familiar approach, designed similarly to wind turbines, underwater turbines rely on the tidal pull of the water rather than waves, turning the arms of the machine and creating a steady source of energy. Water turbines, though, present a significant threat to marine life that may be hurt by the many moving mechanical parts; efforts are being made to prevent any collateral damage to the environment. Another proposal, called the Sea Serpent, is at work floating off the coasts of Scotland, where jointed segments flex along with the movement of the waves to power hydraulic pumps and store energy that is delivered to the shore by underwater cables.

All the models must be designed to survive the ferocious storms that the ocean can deliver, and the fifth model banks on its simplicity to survive. As the low profile machine floats atop the water, it funnels high-pressure water through a pump to shore, where the majority of the machinery remains to convert the water pressure into electricity. This design has already proven itself in its two-and-a-half-year lifetime working on the seas.

Each of the projects has its challenges, but the real vision of clean and renewable energy helps overcome the hurdles that arise with the advent of new technology. 

Higher Hopes for Better Water

By: Jessica Robertson

The number of techniques for assuring water quality is surprisingly high. However, without detailed testing within a laboratory, few techniques are capable of testing all the important parameters of what really constitutes quality water, but portable water quality tests give more accurate information on what the current state of the water may be.  Given the limitations of the portable tests, any particular test could pass water as drinkable when, based on incomplete information, certain pollutants could be present. This situation makes water quality a major issue for poorer communities who cannot afford laboratory analysis, or those who utilize a natural resource for their water supply.

             Using an existing technology known as UV-Vis spectrometry, which is often used in water testing, a team of researchers from North Carolina State University has created a set of algorithms that combines several testing parameters to increase the amount of and quality of information in each water test. Since UV-Vis spectrometry works by measuring the wavelength of light absorbed by the water, the technology capitalizes on its ability to collect data often, getting a reading as often as every 15 seconds, and over an extended time period. These are definite advantages over traditional water sampling, where a sample of water must be collected and analyzed in a lab setting. Typically, UV-Vis technology only measures a few key information points about water quality, but with the algorithms the researchers are using, the data is comparable to what could be done within a lab setting.

            Since the technique increases frequency of testing without eliminating accuracy, natural resource managers and those without laboratory access will be more assured that their sources are suitable for use, that treatments are appropriate, and that the population is not put at risk.