Behind the buzz and beyond the hype:
Our Nanowerk-exclusive feature articles
Posted: Aug 15, 2007
Water, nanotechnology's promises, and economic reality
(Nanowerk Spotlight) Freshwater looks like it will become the oil of the 21st century - scarce, expensive and fought over. While over 70 per cent of the Earth’s surface is covered by water, most of it is unusable for human consumption. According to the Government of Canada’s Environment Department, freshwater lakes, rivers and underground aquifers represent only 2.5 per cent of the world’s total freshwater supply.
Unfortunately, in addition to being scarce, freshwater is also very unevenly distributed. The United Nations has compared water consumption with its availability and has predicted that by the middle of this century between 2 billion and 7 billion people will be faced with water scarcity.
It gets worse: In the developing countries, 80 per cent of illnesses are water-related. Due to the shortage of safe drinking water in much of the world, there are 3.3 million deaths every year from diarrheal diseases caused by E. coli, salmonella and cholera bacterial infections, and from parasites and viral pathogens. In fact, between 1990 and 2000, more children died of diarrhea than all the people killed in armed conflicts since the Second World War.
The use of nanotechnologies in four key water industry segments - monitoring, desalinization, purification and wastewater treatment - could play a large role in averting the coming water crisis. But hoping that the 'magic' of nanotechnology will solve all water problems is naive - the basic problems of accessibility to technologies, affordability, and fair distribution still need to be solved.
Unlike with so many other issues that seem to concern only Third World countries, people in the developed world can't afford to sit back and take a hands-off approach to this problem. The impact of water shortage goes far beyond widespread diseases in the developing world. In the past 15 years, global water consumption has risen at more than double the rate of population growth, due in part to industrial demand. For example, it takes 300 liters of water to produce 1 kilogram of paper, and 215,000 liters to produce 1 metric ton of steel. Changes in our diet are also driving water consumption; it takes 15,000 tons of water to produce a ton of beef, while it only requires 1,000 tons of water for a ton of grain (these numbers are from the Canadian Freshwater website, mentioned above).
So nanotechnologies, or technology in general, should not be seen as a cure all: a lot of problems arise from the way we chose to live (in the rich countries, where we have a choice) and the preferences we set as politicians, producers and consumers.
It is also important to note that many conventional technologies already exist that effectively remove bacteria, viruses, coliforms, and other contaminants from water; water desalination is a proven technology; and wastewater treatment plants do exist. Some of these solutions are expensive; some are affordable and can be produced locally. With enough political will, a lot of funding, and smart and sustained logistical efforts all these technologies could be made available where needed. Saudia Arabia, for instance, produces 70 per cent of its drinking water from desalination plants (no nanotechnology involved). However, one industrial-scale plant costs roughly one billion dollars and one cubic meter of water costs a bit over $1 to produce.
As for water purification, a review of the literature suggests that several technical challenges remain with regards to the cost and effectiveness of removal of certain contaminants in a manner that meets the needs of people in developing countries. That's where nanotechnology comes in because it could increase the effectiveness of existing water treatment solutions and, so claim the proponents, be made available at a much lower cost. There is a good discussion of these issues in the Meridian Institute's Background Paper for the International Workshop on Nanotechnology, Water, and Development (the event took place in October 2006 in Chennai, India). This report is especially helpful to understand what the conventional water treatment technologies are and where nanotechnology-based technologies could improve upon them. In case you want to read up on this issue, there is another good report from Meridian that looks especially at water filtration nanotechnologies (Nanotechnology, Water, and Development)
It is misleading, though, to suggest that nanotechnologies will magically change this picture anytime soon. Almost all proponents of nanotechnology-based water treatment technologies claim that nanotech will make it more affordable. That may be the case some time in the future. You need to make a big leap of faith to buy this argument today. Firstly, most nanotechnology-based applications are still in the lab or have barely made it to the fab. None of them has been scaled up to industrial levels yet – a major prerequisite to bring prices down – and by looking around at what nanotech products are commercially available it appears that some even claim a price premium. Not a single product out there advertises to be cheaper because it is nanotechnology-enabled.
Let's also be clear that all nanotechnology applications proposed for water applications today are evolutionary, i.e. they will offer some improvements over existing devices and applications, not a revolutionary new way of doing things. In case you only vaguely remember your Economics 101 class, here is how profit-oriented companies operate – they will introduce new materials or technologies in their products or production processes for basically one of two reasons: 1) the new technology allows the company to offer an improved product which could be sold at a higher price (which could, but doesn't have to, result in a higher margin, depending to what degree production costs rise) and/or gives it a performance advantage over the competition; 2) the new technology allows the company to reduce its production costs (sometimes even while improving product quality and features at the same time), in which case it could offer the product at the same price and achieve a higher margin, or, if competition is tough, reduce its price.
Reason one clearly is not an option for improving water quality around the globe because it would make things even more expensive than they are today. That leaves reason two: companies need an economic incentive to introduce nanotechnology in their applications. As with all other areas (especially in energy) this industrial scale-up needs to happen for more effective nanotechnology-enabled products, that could help solve real problems, to hit the market en masse (and not just make your car's paint more scratch resistant or you golf ball fly straighter).
"Before these technologies can make the leap from the laboratory to the mass market, they will need to clear the hurdles of public acceptance and economic feasibility" says Lynn Foster, the Emerging Technologies Director of Greenberg Traurig and co-author of a recent article in Nanotechnology Law & Business ("Nanotechnology in the Water Industry"). "Many of these applications are still in their infancy and will require further testing to prove their reliability. Furthermore, implementing many of these technologies will require additional capital investment by existing water treatment centers to upgrade equipment and train personnel. However, though the proponents of nanotechnology face a challenge in convincing private and public entities to incur the up-front costs of adopting these new water purification technologies, nanotechnology holds out the promise of long-term benefits in the form of decreased costs of purifying the world’s water supplies and the enormous savings that would accompany reliable access to potable water in those areas of the world that currently suffer from lack of adequate drinking water and basic sanitation services."
A very good example of how tricky the introduction of new technologies is, just look at your own personal behavior. You can buy nanotechnology-based water filters for your home today, for instance Brita filters which you just screw onto your kitchen tap. That gives you perfectly good, safe and fine-tasting drinking water. Chances are, though, that your fridge is stocked with bottled water; an alternative that, although you couldn't taste the difference to filtered tap water, is more expensive and ecologically damaging. Could it be that you are influenced by the ubiquitous ads for the oh-so-healthy products of the bottled water industry? If you bought Brita and other companies' filters you would support companies like Argonide that push nanotechnology in their products. If you buy bottled water you support companies like Coca Cola. Brita, Argonide et. al. can't afford the huge advertising budgets of the food giants but an informed consumer shouldn't be misled by advertising anyway (nice theory...). Let's just say we agree that water filters are a better choice than plastic bottles. What then will it take for a consumer society to change its behavior and switch to the beneficial technology? Which in turn would bring the price of this technology down and help spread its reach.
In conclusion, there are three points to make. The first is that conventional technology and political will today could solve a lot, if not all, of the water problems the world is facing. At considerable cost. The second is that nanotechnologies, in theory, could make it easier to solve these problems if the hurdle of commercialization can be overcome; because as long as nanotechnology-enabled products are more expensive than their non-nanotech alternatives, we'll face the some problems that we already are having today. And lastly, no matter how promising a new technology is, if entrenched economic interests have different goals, it is hard to reap the benefits of the new.