Over the past year, the staff here at Pollution Engineering has kept its collective eyes out for descriptions of new technologies that could help improve our environment and our lives. This year, there was a huge emphasis on energy-related ideas. Solar panels were mounted over parking lots, cemeteries and even on floating man-made islands. Windmills spilled into our waterways and off our shores. The blades were redesigned so that the machines could safely be placed on rooftops of high-rise buildings and not be overwhelmed structurally by the forces they tried to harness. Two large solar farms were constructed to focus the sun's rays to superheat water.

Engineers in 2008 built walls that can clean the air on contact, or generate electricity as the sun shines on the building. They placed windows that can be transparent or opaque on command. The search for energy took us from the depths of the oceans to the stratosphere.

There were also a few that raised eyebrows. One machine claimed it could be started and would continue to produce power with no external energy source. Upon closer examination, we determined that it only worked as long as a battery was connected to it. One fellow wanted to attach large-diameter pipes to high-rise buildings or on the sides of mountains. His idea was that the air was colder and would naturally fall down the pipe where it could drive a turbine.

Not every idea becomes technology. But there is a point in the evolution of everything that works when once it did not, and such advancements may never have taken another step were it not for dedicated inventors who refused to give up.

It is in honor of these visionaries that we present the 10 technologies that PE's editors think could have an affect on this industry in 2009 and beyond. They are not presented in any particular order and the magazine makes no claims on any of their capabilities. Some are ready for production, others barely past theory. But these 10 inventions will be worth keeping an eye on this year.

1. Capturing CO₂

Graduate student Jeffrey Drese displays a tubular reactor filled with the hyperbranched aminosilica adsorbent dispersed in sand. The reactor is used to test the new material for its ability to capture CO2.

With national carbon control on the horizon, new technology for the capture CO₂ has been in high demand. Two new technologies on this front have stood out.

The first comes from the Georgia Institute of Technology, which in 2008 announced a new material that will provide a low-cost method of capturing CO₂ from smokestacks of coal-fired power plants. The material is called hyerbranched aminosilica and was detailed in the Journal of the American Chemical Society on March 19, 2008. The material is not difficult to manufacture. Tests showed it was able to adsorb the gas at temperatures between 50° and 75°C. It can be regenerated by heating it to between 100° and 120°C. The gas could then be stored deep in the ocean, or in abandoned coal mines or empty petroleum reservoirs.

The second interesting item is a rock called peridotite. It is commonly located in the Earth's mantle. Scientists from Columbus University's Lamont-Doherty Earth Observatory in New York say that they only need to bore down to this layer and inject heated water containing pressurized CO₂. The rock naturally reacts with the gas to form a solid carbonate similar to limestone or marble.

2. Power to the Neighborhoods

Another way to control CO₂ emissions would be to not produce any. A company named Hyperion suggests they may be able to provide nuclear energy to neighborhoods of 20,000 average-size American homes or the industrial equivalent.

Their solution is a small nuclear facility. The main reactor is buried deep underground. There are no moving parts and no maintenance required. The unit is secure as there is no access; it can remain thus sealed for 10 or more years. The pumps and generators are located aboveground for easy access.

Such small-scale nuclear power has been used to drive Navy submarines and warships for many years without incidence, lending credibility to the concept. Security would be easier than defending a large facility with huge stacks.

3. Are You Using that Ocean?

Japanese scientists are working on a design for massive floating power generators. A group from Kyushu University is exploring the use of huge cleantech generators that would float at sea. The rigs would incorporate massive photovoltaic generators and turbines, and could generate as much power as a nuclear facility according to scientists on the project. At 2 kilometers by 800 meters, the massive flowats would each generate about 300 megawatts of electricity.

The rigs would have the dual purpose as de-facto nurseries for seaweed and algae; LEDs would shine light into the seawater, stimulating the growth of aquatic plant forms, which in turn absorb CO₂ and attract fish and plankton.

The research team began testing a floating base for a generator in July 2008 and plan to test a model of a generating plant this year.

4. Growing Up Green

One of the less-voiced challenges of controlling greenhouse gases, particularly CO₂, is the concern that as soon as the developed world manages to significantly cut their emissions and fossil fuel use, the developing world will simply step in and emit everything that older industrialized nations cut. Students at the Massachusetts Institute of Technology, however, may have found a way to bring clean, renewable energy to developing world communities. The project, which in November 2008 received a $10,000 grant from the federal EPA, uses solar heat and methane gas to create power. The systems are highly customizable in order to use the solar and organic resources available to each particular region. By focusing on solar thermal, biogas and algal CO₂ technologies, the MIT systems should increase efficiency and decrease CO₂ output over the typical diesel generators used in such areas.

Such generators are hardly the sole property of developing communities. Site remediation projects, for example, could potentially use the MIT systems to power their equipment with locally available organics, even, perhaps, the organic material being remediated.

5. Zero-Emission Fuel

A new catalyst may provide a method of cost-effectively producing hydrogen from ethanol. But the energy needed to break the chemical bonds and produce enough of it seems to be a deterrent to mass production.

Umit Ozkan, professor of chemical and biomolecular engineering at Ohio State University, believes he has a catalyst that can break hydrogen from ethanol with a 90-percent yield at a workable temperature and be very cost-effective.

"Rhodium is used most often for this kind of catalyst and it costs around $9,000 an ounce," said Ozkan. "Our catalyst costs around $9 a kilogram."

Ozkan presented her results at the American Chemical Society meeting in Philadelphia on Aug. 20, 2008. While there still remains a number of issues that need to be resolved such as transportation, storage and distribution, this discovery would make the cost of manufacturing energy-grade hydrogen very reasonable.

6. From the Battle Lines

Science is focused on finding methods to thwart terrorists by detecting materials that could cause harm, but in doing so, may have stumbled upon a technology for detecting trace substances simply by pointing at it. Researchers at Oak Ridge National Laboratory are working to develop this Star Trek-like equipment that they call standoff photoacoustic spectroscopy. The technology would allow an investigator to literally stand at a distance from a substance and detect hazardous compounds.

Essentially, it is a laser light that excites the materials. The device then measures the sound signature captured from the reflected light as it generates a vibration through an interaction with a special tiny quartz crystal.

The researchers expect to be able to expand the range of their equipment with stronger lasers and detect trace amounts of hazardous substances.

7. Better Batteries

What is stopping mankind from powering cars and cities with solar energy, or establishing a colony on Mars, or visiting other galaxies? A longer-lasting battery. While Earthlings are likely Earth-bound for the foreseeable future, a breakthrough in battery technology could keep our laptops and cell phones running longer.

Stanford University scientists spent much of 2008 looking at the commercial viability of a battery that could keep a laptop powered for 40 hours, or a cell phone charged for a month. Assistant professor Yi Cui and his associates at Stanford's Department of Materials Science and Engineering believe they can increase the life of a rechargeable lithium-ion battery tenfold by using silicon nanowires, rather than graphite, as the battery anode.

Scientists have known that silicon anodes have the highest theoretical charge capacity, but have not been practical because they change volume by up to 400 percent as lithium is inserted and extracted. Cui's solution is to organize the silicon like a sponge of nanowires, each of which expands but would not fracture. The structures would have similar organization and resiliency as follicles on a hairbrush.

The materials would experience little change in charge capacity during cycling, meaning the batteries themselves would last for decades.

The better battery may not take us to the moon. But any environmental professional who has worked in the field or run around a plant could vouch for the utility of a computer or handheld battery that could hold a charge 10 times as long, and perhaps never need to be replaced.

8. Cementless Concrete

Georgia Tech researchers have developed a process to use coal ash to produce a concrete material that uses no cement. The end product is strong and lightweight, along with other advantageous characteristics.

Coal-burning power plants must dispose of over 125 million tons of ash each year. Mulalo Doyoyo, an assistant professor in Georgia Tech's School of Civil and Environmental Engineering developed a trademarked material called Cenocell that is a proprietary mixture of the bottom, or fly, ash mixed with organic chemicals to form the new material. Sand and aggregate materials as well as the cement are not required. The resulting material can withstand pressures up to 7,000 psi. It is also fireproof. It can be shaped in molds and machined as needed for building construction projects.

Doyoyo believes the material would reduce the use of cement, thus reducing emission of CO₂ gas that is normally given off during its manufacture. He expects the product will cost an average of $50 per cubic yard to produce. Anticipated uses for the product are building and construction, transportation, aerospace and protective installations.

Doyoyo will next be presenting his findings at the World of Coal Ash convention, May 4-7, 2009 in Lexington, Ky.

9. Power to the Peaches

Caye Drapcho, a biosystems engineer at Clemson University in South Carolina, is investigating a bacterium that produces hydrogen. The microbe is called Thermotoga neapolitana and it has a sapidity for peaches, especially rotten ones. Drapcho notes that peach waste in particular has a high percentage of sugars that can be converted to hydrogen gas. Considering approximately 20 million pounds of damaged peaches are discarded per year in South Carolina alone, her research may help turn crop losses into fuel.

Clemson researchers also made advances this year in obtaining fuels from grasses and trees, particular fast-growing poplar trees. Cellulose is the plant material used to make ethanol. Another plant material, called lignin, impedes processing into fuel. Geneticist Haiying Liang is seeking to breed poplars with a lower lignin content that could improve biofuel production and be less costly to process without harming the tree's growth.

10. The Reverse Salt Shaker

Adding just the right amount of salt is never easy, but getting salt out of water is much trickier. Large-scale desalination has long been an important method for oceangoing vessels and seaside communities for obtaining potable water. But advances in desalination technologies in 2008 and 2009 could make this a more viable, inexpensive solution for regions like the U.S. South and Southwest in search of greater freshwater resources for their growing populations.

Much of the falling costs of the technology in recent years have come from incorporating reverse osmosis treatment, which lowers the temperature of the desalination process and allows the plants to meet the stringent regulatory discharge requirements. Combining effluent with that of a nearby wastewater treatment plant or power plant allows the brine to dissipate to an acceptable salinity level.

Just how far desalination has come was demonstrated in late 2008, when the state of California, known for its prickly attitude toward environmental threats, authorized the construction of the largest desalination plant in the Western Hemisphere in San Diego.

Recycling technologies used in large naval vessels, a pilot plant in Russia is testing a small nuclear reactor for powering desalination, with cogeneration of electricity using low-pressure steam from the turbine and hot sea water feed from the final cooling system. PE