How nanotechnology can impact the resource economy to drive green innovation and sustainability

The very real need to address energy, agricultural and industrial sustainability is a key priority for many nations and nanotechnology is fast becoming an powerful enabler to combat the threat of resource scarcity and climate change.

One of the striking disproportions of public perception over nanotechnology and its future application is the inordinate bias placed on the consumer goods market and the benefits that will be realised in particular across consumer electronics. Whilst it is certainly true that nanomaterials are currently being used in developing next generation smart phone and tablet screens and chargers, televisions, tennis rackets, stain and waterproof trainers and even biocidal surfaces for refrigerators, aren't we missing the big picture here in terms of the real impact of nanotechnology?

Of course, this reporting bias on consumer applications is to be completely expected when communicating science and technology with the general public, as people are inherently interested in "what's in it for me?" The advances in electronics and medicine in particular from nanotechnology show no sign of slowing in bringing us new sensational headlines. But is talk of smartphones going to be enough to galvanise and inspire society to address the critical needs of the 21st century? The potential uses of nanomaterials across bulk industrial applications such as construction, transportation, energy generation and water treatment, whilst not as exciting to most, have the capability for much further reaching positive change in addressing some of the more pressing issues that humanity faces in terms of resource scarcity and climate change. By reducing emissions, consuming less fuel or using less materials for the same output or even better performances there are enormous energy efficiency improvements to tap into across the industries where our consumption of resources is greatest. If nanotechnology is to bring about the next industrial revolution as is often cited, surely it will be driven by changes to the world's resource economy (production of energy, materials and food) rather than household gadgets and sports equipment.

If we look at water for example, whilst considered by many as abundant since more than two thirds of the earth's surface is covered in water, approximately 97% of that is salt water and almost 2% is snow and ice, which leaves 1% to provide for the world's agricultural use, power stations, drinking and bathing. By 2030 current water supplies will only satisfy 60% of the total global demand, which will create pressures on the cost of water and/or restriction of its consumption. The World Economic Forum (WEF) has placed the water crisis as number 3 in its top 10 global risks of highest concern in 2014. 50 million m3/day of our water is produced from desalination methods . Desalination is an energy intensive process and for many nations cost reduction through new technologies is needed to make it affordable and accessible. Current desalination membranes, thin-film composites that employ the reverse-osmosis process, achieve a high salt rejection (over 99%) but have low permeability to water so the flow rate is slow. The development of new desalination membranes engineered with nanomaterials is likely to be one of the most effective ways to increase production capacity, reduce cost and energy use in the process and reduce the resource scarcity.

The second most consumed product on earth, after water, is concrete. The world consumes around 20 billion metric tonnes of concrete each year. Although cementitious materials are so widely used, they tend to have poor mechanical properties and suffer from high permeability to water and other damaging chemicals which causes low durability. Production of cement used in concrete materials is also one of the largest contributors to CO2 emissions (5-6% of global man-made CO2 emission annually, which is greater than that of the aviation industry). The need for stronger, more durable and functional building materials across the construction industry to reduce cement consumption and lower emissions contributions is driving development of advanced structural composites using nanomaterials. Addition of nano-silica, carbon nanotubes or graphene for example has the potential to improve crack resistance, curing time, tensile strength, flexural modulus, ductility, and reduce water absorption. Smart properties can be introduced as well, such as sensor capabilities for building materials to detect damage of the structures they uphold, and applications of self-cleaning and pollutant reducing building and road surfaces with use of nano-scale titanium dioxide additives. 

It is also estimated that across the industrial sector as a whole, somewhere between 20-50% of energy use is lost as waste heat (through hot exhausts, cooling water and equipment surfaces). Advances in thermoelectric materials through nanotechnology have illustrated conversion efficiencies of 15% or greater which will provide future improvements to recovering waste heat losses and therefore improve energy efficiency and cut emissions.

In the transportation sector, which now accounts for 23% of the world's CO2 emissions from fossil fuel combustion, the use of nanocomposite materials when applied to lightweighting vehicles have the capability to dramatically reduce fuel consumption and emissions. Through also applying nano-coatings, for example to a ship's hull to create antifouling surfaces or on aircraft exteriors to prevent ice build-up, significant levels of fuel can be saved by reducing friction and drag. But perhaps the biggest trend in transportation is occurring in the road transport sector, where the market for lithium ion battery powered vehicles is growing fast (CAGR 37%) , where it is anticipated that carbon based nanomaterials such as graphene and carbon nanotubes will play a significant role in new electrode materials to deliver higher energy densities, shorter charge time, longer cycle life and charge lifespan and improved safety. Further application of nanomaterials is also expected in next generation and future generation energy storage devices such as supercapacitors, hydrogen fuel cells and solid oxide fuel cells.

Lubricating oils are some of the most widely used products that play an essential role in keeping the smooth running of industry by reducing friction (improving energy efficiency) and reducing wear (maintaining productivity by preventing component failure and machine downtime). As industrial and transportation activities increase, the need to improve efficiencies in fuel consumption to mitigate greenhouse gas emissions grows larger. Despite the widespread use of lubricants, a significant proportion of energy is still used overcoming friction in moving mechanical systems. Across industrialised countries, the annual cost due to friction and wear related energy and material losses is estimated to be between 5-7% of national GDP. Use of performance-enhancing additives is commonplace in modern lubricants but nano-scale additives based on copper, boron, WS2, MoS2 and graphene can drastically improve performance resulting in potential reduction in petroleum consumption in the order of millions of barrels per day and reducing CO2 emissions by millions of metric tonnes each year.

Energy generation itself also provides a number of routes for nanotechnology to address the growing energy needs of the planet and the need for cleaner sources of energy. If we look at the current situation with hydrocarbons, as deposits become more technically challenging to exploit, the need for enhanced oil recovery methods is at an all-time high. Oil sands and shale-rich rock formations represent about 4 trillion barrels and 345 billion barrels of recoverable oil respectively, through heavy oil recovery and fracking. If these sources are to be most effectively and responsibly tapped, by employing nanofluids to alter the oil/rock surface interaction (wettability), and nanoemulsions to withstand higher temperature and pressure conditions, and nanocatalysts to reduce viscosity, the total yield of the production sites can be vastly improved. Furthermore, with advancements in water treatment technologies using nanomaterial membranes, the ecological impact of these activities can be mitigated by filtering out heavy metals and other pollutants. 
When burning fossil fuels, nanocatalysts such as cerium oxide can deliver not only increased fuel efficiency but also reduce emissions and pollutants by providing more complete combustion. In diesel engines a reduced fuel consumption of 8-14% can be observed, along with reduced soot by up to 40%, reduced unburned hydrocarbons by up to 70% and reduced greenhouse gas emissions between 20-40%.

In reducing reliance on hydrocarbons, renewable sources of energy need to be made more economic. Two convergent fields in technology; that of solar cells and printable electronics may provide that solution to offer an affordable, ubiquitous green source of energy. Once again, nanotechnology is enabling this movement from vision to reality by delivering more energy efficient photovoltaic systems. There is a broad range of different solar cell designs, processes and techniques that are at varying points along the cost-curve, which I will not elaborate on within this article, but suffice it to say there is healthy competition in the solar market and it is only a matter of time before some of these processes can deliver on the price-to-performance that will see much wider uptake of our largest, unfailing source of natural energy.

Also one of the most important issues of this era is the global food crisis, currently 8th in the WEF top 10 risks of highest concern in 2014. Mineral depletion in our soil has been sourced as a growing problem linked to poor crop yields and lower nutritional value of produce. High intensity farming has put a strain on the top soil and whilst nitrogen and potassium are often replaced with standard fertilisers, many other important micro nutrients are often overlooked such as iron, zinc and manganese. The introduction of nano-fertiliser products can radically enhance uptake and enrichment of minerals through the soil. In wheat varieties for example, as much as 99% increase of grain yield and 32.4% increase of grain iron levels can be observed compared with control samples.

The use of nanotechnology therefore has the potential to significantly change the landscape of the resource economy, but it is vital that nanomaterial supply chains are organised to be capable of delivering the high volumes needed to place these technologies in serious contention to meet the world's critical needs in the markets for energy generation and storage, bulk materials and agricultural production.


Harvard Business School
International Desalination Association
US Department of Energy
Frost and Sullivan
Argonne National Laboratory
Khazra nano chelate fertiliser product (M. Rezaeei et al. / Scientific Journal of Crop Science (2014) 3(2) 9-16 )