London-based nanotech analyst company Cientifica has published a report asserting that nanotech is actually just greentech in disguise.

The report specifically points to six major ways in which nanotechnology is contributing to the reduction of carbon emissions. The six technologies discussed are all available now or within the next two years, its authors say, and some have been making stealthy inroads into global industry for as long as a decade.

The six applications identified in the report:

Aerogels - Often known as frozen smoke, an aerogel weighs just twice as much as air and comprises a tangle of silica containing as much as 99.5% air. In the manufacturing process, tiny pockets of between 5 to 150 nanometers across are formed.

The report calls aerogels an attractive substitute for glass in architectural applications such as skylights and roofing. Rather than trying to generate energy with PV panels, it can be easier to let the sun shine in and then trap the heat, the authors say. The need for artificial lighting can be reduced. Nanogels can also be incorporated into traditional glazing to further increase energy efficiency.

For more on aerogels, read Cleantech.com's Nanotech starting to gel.

Thin film solar - Organic thin film cells, or plastic solar cells using low-cost materials based on nanoparticles and polymers, represent promising alternatives to pricey silicon, the report says.

It predicts nano-based thin film solar cell efficiencies will eventually reach similar or greater levels than existing silicon, noting that development has been spurred by the large amount of funding going into both nanotechnologies and renewable energy.

Fuel borne catalysts - Substances that help diesel fuel burn more efficiently in the engine, increasing fuel economy and reducing particle emissions. Nanoparticles of materials such as cerium oxide are added to fuel and help the fuel burn more evenly and longer.

The report cites long term trials by U.K.-based Oxonica that have indicated improvements in fuel efficiency of up to 10% and a reduction in soot emissions of around 15%, reducing both carbon input and output. Applying the technology to private automobiles in the United States could reduce emissions by 30 million tons annually, the authors forecast.

Fuel cells - The report characterizes fuel cells as a nanotechnology, specifically pointing to the latest generation of small direct methanol fuel cells (DMFC). It calls automobiles the "key application" for fuel cells, contrary to others' views that cars of the future will be electrical (see Cleantech.com's Hydrogen cars non-starters.)

Supercapacitors - Electrical storage devices that can store a high density of energy in a short time based on increased surface area by using nanomaterials.

The energy density of supercapacitors is 10 times higher than in normal batteries, allowing their use in portable electronics, electric vehicles and potentially for storing energy generated from renewable sources such as wind and solar power, the authors said.

Nanocomposite materials - Polymers to which an amount of another material, such as nanoparticles, clays or carbon nanofibres have been added in order to alter the properties of the bulk material. This is one of the oldest applications of nanotechnology, the report says, in use since the 1990’s.

Replacing steel with lighter materials such as nanocomposites can generate huge fuel savings in everything from automobiles to aircraft, the authors note. They forecast an increasing use of nanocomposites in the automotive sector, even under the hood.

"All of the key applications are related to our enhanced control of materials at the nano scale, whether lighter stronger materials for transportation, better thermal insulators or more efficient ways of storing energy," said Cientifica CEO Tim Harper, whose organization claims to have a twenty year background in nanotechnology.