Heiner Markhoff, Straits Times 20 Jun 09;
IT IS often said that an economy runs on oil, but it could just as easily run on water. Simply put, electricity is needed to power the economy, and power cannot be generated without water. Conversely, electricity is needed to treat water.
It is therefore critical that we consider the nexus between water and power.
A large amount of water - up to 90 per cent - is used in any power plant for cooling purposes. This water can be recycled. Water is also used to produce steam for power generation.
In a world where water is an increasingly scarce resource, policies supporting its conservation and recycling for power generation must be an urgent priority.
It is estimated that 15 per cent of freshwater worldwide is used for industrial purposes. And as this sector grows, so will demand for power and water.
In the United States, water demands related to electricity production have almost tripled since 1995, and nearly 90 per cent of all industrial water is used for the generation of power.
In France, power generation has become the largest water guzzler.
Singapore's non-domestic sector uses about half the treated water supply. The country has become a champion of water conservation and recycling to support its industrial growth and other water uses.
The Republic is already reusing 15 per cent of its waste water and plans on doubling this to 30 per cent by next year.
Australia reuses about 8 per cent of its waste water and has set a national target of 30 per cent by 2015. The US reuses only about 6 per cent. In many other parts of the world, the ratio is even smaller.
It is clear that water reuse is not as prevalent as it is should be.
One effective way to achieve water savings is to co-locate water-treatment facilities and power plants.
A US Department of Energy-sponsored study looked at 110 new proposed power plants in 2007. It found that municipal waste-water treatment plants located within a 40km radius of the proposed power plants could satisfy 97 per cent of the power plants' cooling-water needs.
Incentives to co-locate municipal waste-water treatment plants and power generation plants would go a long way towards reducing freshwater withdrawal.
Moreover, reusing water often reduces energy consumption in and of itself. A 1,000MW power plant with a water-reuse system for cooling-tower water recovery will reduce the energy otherwise needed to produce, distribute and treat fresh water by a net 15 per cent - enough to power some 350 homes for a year.
However, while advanced water reclamation technologies already exist, the motivation to deploy them often does not.
Today, it is often less expensive for plant operators to get water from a river or well, or even use potable water, than to treat and reuse it.
Policy incentives have been primary drivers for growth in renewable energy capacity. Similar legislation and incentives to jump-start the widespread use of new water recycling technologies are needed.
Incentives are particularly important since new technologies are often more expensive compared with current technologies that have developed infrastructure and economies of scale.
Singapore, for example, has already established a water efficiency fund to provide up to half of the capital costs of water recycling facilities for companies.
The Singapore International Water Week that begins on Monday will be a meeting of minds and a good platform for global leaders to consider such forward looking strategies.
The proposed federal Energy and Water Integration Act of 2009 in the US calls for a study on how energy development affects the nation's water supplies.
It would also be beneficial for the federal government to identify best available technologies to minimise the use of water in the production of electricity.
There are significant energy and water savings to be gained in the area.
The opportunity to achieve these goals is within reach: The cost of new technologies has fallen. Also, new generation membranes and better management practices have contributed to reducing the energy cost of seawater desalination to one- third of what it was a decade ago.
Global water use is expected to rise by up to 30 per cent in developing countries and more than 10 per cent in industrialised countries by 2025.
By 2030, two-thirds of the world's population may experience moderate to high water-supply concerns. And global electricity demand is expected to double.
Energy and water truly are co-dependent resources, critical to the functioning of modern economies and to life itself.
We must respect this inter-dependent relationship so that we can better manage the ways we acquire and use these resources. Only then can there be sustainable growth in the years ahead.
The writer is president and chief executive officer of water technologies developer GE Water.
