The implementation of nanotechnology into wind energy applications, is bringing together different methodologies and techniques to address more effectively some of the great challenges facing the science of wind engineering. The most critical part of this accomplishment, is to stimulate a harmonious integration of scientific and technological endeavors for the next generation of wind turbine models .

The main scope of nanoscale technology, is to improve the durability of the critical energy system components and stabilize their performance during generation, transportation and distribution with the lower maintenance cost as well as, with significantly fewer greenhouse gas (GHG) emissions to the atmosphere. In addition to that, the innovative nanomaterials and nanosensors could be used to lend a helping hand for the renewable energy smart grids integration and energy production decentralization.

Nanoscale processes, materials and devices, have already been introduced into the wind industry and contribute to the development of new standards for wind turbine performance, availability, operability and reliability. Nanoscale models are being developed to prolong the lifespan of wind turbines, mitigate the fatigue failures of structural components and lower the overall cost of energy generation.

Weight Saving

To increase the electric power produced by a wind turbine, blades must grow in length, since the power captured by a wind machine is proportional to the square of blade length. At the same time, blades must be kept as tight as possible. Nanocomposite materials with excellent strength-to-weight and stiffness-to-weight ratios are now being used to facilitate the development of next generation high-performance blades.

Nanoparticles are used to equip other materials with new properties in order to achieve novel functions. The synthesis of these multifunctional nanocomposites involves the use of low molecular weight polymers (di- acetylenes) which generally have long-term stability and excellent processability. They also have good diffusion barrier properties and exceptional water repellency. Here are some of their advantages and disadvantages:

1	Tensile strength up to 40%
2	Tensile modulus (elasticity) up to 68%
3	Flexural strength up to 60 %
4	Flexural modulus (bending) > 126%
3	Distortion temperature from 65% to 152%
3	Improved flame retardant properties<

Disadvantages

1	Recycling difficulty
2	Brittleness
3	Inadequate price / performance ratio
4	Difficult compounding requirements

Nano-Lubricants

The rotating parts of the wind turbines are experienced high static and dynamic loads coming from the turbine blade and wind alteration. Also, because of the unsteady operating conditions and due to the presence of debris, system failure is accelerated. Scuffing, fatigue cracking (from cyclic stresses),

Novel Sealants Based on Nanocomposite Elastomer

hydrogen embrittlement failures, tribo-corrosion (the degradation process of the material) and micropitting of the rotating parts, are the most important damage mechanisms of the structural components.Maintenance activities and replacements are costly and contribute to significant downtime of the wind energy plant. Nanolubricants with extremely low friction coefficients meteorology have been developed to reduce energy losses in the rotating parts of the wind turbine (gearboxes and bearings) and maximize energy system efficiency, as a sophisticated protective line of defense. Nanolubricants use the geometrical structure of nano particles, which behave like mini ball bearings, to provide extraordinary anti-wear and protection.

De-icing Coatings

The development of superhydro-phobic and ice-phobic structure materials is a revolutionary idea. A set of environmentally friendly deicing coatings, can effectively keep wind turbine blades, sensors and measurement equipment free from ice accumulation. A related paradigm is the implementation of carbon nano-tubes (an allotrope of carbon with a cylindrical nanostructure, 50-110 times stronger than steel and 6 times lighter) for coating the rotor blades surface. A small electric current is applied to the blades surface, next the nanotubes heat up and thus preventing ice formation. Lotus Effect® by Degussa Germany is one of the most advanced nano-based products for the prevention of ice-forming phenomena.

Novel sealants based on nanocomposite elastomers

Offshore wind energy projects should be able to withstand rough weather conditions. Identifying and eliminating the source of moisture, is a critical concern for offshore wind energy plants. Recently, novel sealants based on nanocomposite elastomers have been developed, to facilitate the integration of offshore wind energy plants and assess the processability of composite materials. The pioneering work carried out by Toyota Central Research Laboratories is only the beginning of the story. These nanocomposite elastomeric elements are produced from the interaction between an isobutylene-based polymer and layered nanofiller. Conventional micro-composites, intercalated nanocomposites and exfoliated nanocomposites are the most important categories that should be further investigated in order to promote potential and innovative solutions. In addition to that, the crystallization and mechanical properties analysis of these polymers can provide valuable insights for wind engineeeing and nano-science applications.

Energy Storage and Transmission

Energy storage is considered to be one of the most important factors for the penetration of renewable energy technologies. Nanotechnology can bridge the gap between energy storage and production by applying innovative techniques such as carbon nanotube hydrogen storage systems. The energy density of hydrogen is enormously high by weight, but at the same time its low energy density by volume, turns its storage properties and capabilities into a challenging proposal for the future energy systems. Some other carbon-based nanoscale particles such as aerogels, nanofibres and grapheme can be also used to reduce the dimensions of the storage medium to nanoscale dimensions and effectively address the energy storage challenges. Current investigation focuses on reversible reactions between hydrogen and solid-state materials, such as magnesium.

Concerning the power transmission and nanotechnology, a very interesting research from 7 Scandinavian universities and several institutions, named Nanotechnology for Energy Applications, states that the existing copper-based grids leak electricity at about 5% per 100 miles of transmission. A special type of carbon nanotubes, so-called armchair nanotubes, which exhibit extraordinarily low electrical resistance (more than 10 times better conductivity than copper) and tremendous specific tensile strength, could revolutionize electricity transmission.

Nanotechnology May not Be Handled

Despite the rapid advances in nanotechnology and its revolutionary applications in renewable energy industry, several concerns, ethical and technical, are currently being raised that need further attention. Is the use of nanotechnology environmental friendly? Do we have access to these logistic management and transportation methods for the different nanoscale materials dimensionalities? Coating the blades or rotating parts with too small particles can increase the risk of mass poisoning.

However, the most important one is our knowledge regarding nanotechnology. We currently have the knowledge to develop and design materials and applications with nanotechnology but we still have to expand our critical thinking in order to understand the concept and potential impacts of nanoscience. If we can change the structure and properties of a material at the nano scale with no awareness of the potential risks, we will produce something that in the real world could not be turned into a good cohesive set of functionality. Are these risks completely understood and if so, are we able to normalize and manage them?