This week German Chancellor, Angela Merkel, told lawmakers that tackling climate change will be one of the central tasks of the upcoming Hamburg G20 summit of the world's largest economies, following the U.S.'s withdrawal from the Paris climate pact. Here we look at the 7 ways that nanotechnology can help to combat and possibly stop climate change:

1. Lightweight nano-composite materials - Any effort to reduce emissions in vehicles by reducing their weight , in turn, decreasing fuel consumption can have an immediate and significant global impact. It is estimated that a 10% reduction in weight of the vehicle corresponds to a 10% reduction in fuel consumption, leading to a proportionate fall in emissions. In recognition of the above, there is growing interest worldwide in exploring means of achieving weight reduction in automobiles through use of novel materials. For example, use of lighter, stronger, and stiffer nano-composite materials is considered to have the potential to significantly reduce vehicle weight. 

2. Nano-coatings - Nanotechnology coatings are a good short-term way of reducing emissions and and maximizing clean energy production. For example, nano-coatings can be applied to aircraft, which can make aircraft's smoother, reducing drag and also protect the materials from the special conditions of the environment where they are used (instead of the conventional bulk metals such as steel). Since the amount of CO2 emitted by an aircraft engine is directly related to the amount of fuel burned, CO2 can be reduced by making the airplane lighter. Hydrophobic nano-coatings can also improve the energy produced from solar panels for example.

3. Nanocatalysts - Nanotechnology is already applied to improve fuel efficiency by incorporation of nanocatalysts. Enercat, a third generation nanocatalyst developed by Energenics, uses the oxygen storing cerium oxide nanoparticles to promote complete fuel combustion, which helps in reducing fuel consumption. Recently, the company has demonstrated fuel savings of 8%–10% on a mixed fleet of diesel vehicles in Italy. Reducing friction and improving wear resistance in engine and drive train components is of vital importance in the automotive sector. Based on the estimates made by a Swedish company Applied Nano Surfaces, reducing friction can lower the fuel consumption by about 2% and result in cutting down CO2 emissions by 500 million tons per year from trucks and other heavy vehicles in Sweden alone.

4. Nano-structured Materials - Thanks to nanomaterials like silica, many tires will in the future be capable of attaining the best energy rating, the green category. Cars equipped with category A tires consume approximately 7.5% less fuel than those with tires of the minimum standard (category G). Residential and commercial buildings contribute to 11% of total greenhouse gas emissions. Space heating and cooling of residential buildings account for 40% of the total residential energy use. Nanostructured materials, such as aerogels, have the potential to greatly reduce heat transfer through building elements and assist in reducing heating loads placed on air-conditioning/heating systems. Aerogel is a nanoporous super-insulating material with extremely low density; silica aerogel is the lightest solid material known with excellent thermal insulating properties, high temperature stability, very low dielectric constant and high surface area.

5. Improved Renewables - Nanotechnology may accelerate the technology behind renewables in various ways:experts are discovering means to apply nanotechnology to photovoltaics, which would produce solar panels with double or triple the output by 2020; wind turbines stand to be improved from high-performance nano-materials like graphene, a nano-engineered one-atom thick layer of mineral graphite that is 100 times stronger than steel. Nanotechnology will enable light and stiff wind blades that spin at lower wind speeds than regular blades;nanotechnology could play a major role in the next generation of batteries. For example, coating the surface of an electrode with nanoparticles increases the surface area, thereby allowing more current to flow between the electrode and the chemicals inside the battery. 

6. Batteries - Such techniques could increase the efficiency of electric and hybrid vehicles by significantly reducing the weight of the batteries. Nanotechnology is positioned to create significant change across several domains, especially in energy where it may bring large and possibly sudden performance gains to renewable sources and Smart Grids. Nanotech enhancements may also increase battery power by orders of magnitude, allowing intermittent sources such as solar and wind to provide a larger share of overall electricity supply without sacrificing stability.

Moreover, superior batteries would complement renewables by storing energy economically, thus offsetting the whole issue of intermittent generation.In a somewhat more distant future, we may see electricity systems apply nanotechnology in transmission lines. Research indicates that it is possible to develop electrical wires using carbon nanotubes that can carry higher loads and transmit without power losses even over hundreds of kilometers. The implications are significant, as it would increase the efficiency of generating power where the source is easiest to harness. Semiconductor devices, transistors, and sensors will benefit from nanotechnology especially in size and speed. 

7. Nanotech sensors - Sensors could be used for the Smart Grid to detect issues ahead of time, ie, to measure degrading of underground cables or to bring down the price of chemical sensors already available for transformers. Nanotechnology will likely become indispensable for the Smart Grid to fully evolve in the near future. Energy efficiency is a way of managing and restraining the growth of energy consumption. It is one of the easiest and most cost effective ways to combat climate change, improve the competitiveness of businesses, and reduce energy costs for consumers.

This article is an opinion piece from The World Nano Foundation, for more information visit www.worldnanofoundation.com