TODAY 22 March 2014 is World Water Day, an annual event to mark the importance of water. It is also part of the United Nations's Decade for Water (2005 - 2015) activity.
This year's theme is "Water and Energy". The friendship between water and energy begins when water from the Earth's surface evaporates after absorbing energy from the sun. It then forms clouds, and precipitation begins in the form of rain and snow.
The influence of rain and snow to the ecosystem is vast. The Association of Water and Energy Research Malaysia (AWER) summarises this "friendship" as:
Water generates energy
When water flows from a high altitude, it converts the potential energy stored in it to kinetic energy. This brings forth the water wheel that is used to create mechanical power and vice-versa. Now, water is stored in dams to create potential energy that is eventually converted to electricity via hydroelectric generation power plants.
Wind turbines and solar panels tap into alternative energy resources.
Water uses energy
Raw water needs to be treated to ensure it meets our drinking water quality standard set by the Health Ministry. This requires a substantial amount of energy to treat and supply water. This is mainly due to the electricity consumption by pumping systems that are installed to bring raw water to the treatment facility, the treatment process itself and to pump treated water to demand zones. The cost of water treatment and supply can be viewed as the percentage of ratio between energy cost and total operational expenditure.
Older pumping systems result in higher cost. Gravity feed water treatment and supply system can reduce energy use in water treatment and supply substantially as potential energy stored in water is used to flow the water.
However, densely populated areas with high-rise buildings and locations that are far away from water treatment facilities will still result in higher energy usage to supply treated water.
Wastewater uses and generates energy
Domestic, commercial and industrial sectors produce wastewater. This wastewater must be treated to prevent it from polluting the environment. Treatment processes need a lot of mechanical power that is driven by electricity. This increases the use of energy to treat wastewater. Industrial wastewater that carries hazardous chemicals may use higher energy input.
Nevertheless, sewage and biomass can produce methane, a renewable energy resource. Such a process allows sewage and biomass to be converted into electricity or biogas. Some of the biogas harvested is used for transportation, cooking and industrial combustion process.
Water grows energy (biofuel)
In Malaysia, total water consumption is divided into domestic (17 per cent), industry (including commercial at 21 per cent) and agriculture (62 per cent). Based on the National Water Services Commission's (SPAN) statistics, in 2012, total demand for treated water for the domestic sector is about 5,881 million litres per day (mld).
We can roughly estimate that agriculture sector uses around 21,448 mld of water from both direct and indirect use as there is no direct measurement done.
The need to find renewable energy resource has mooted the creation of biofuel. It is created by converting raw products from starch or oil into usable fuel, such as ethanol or methyl ester. In Malaysia, palm oil is used as the raw material to produce methyl ester that can be combusted.
Water and energy efficiency is our national security and key to our survival
The rapid increase in demand for water and energy will drive a hunt for resources. We should start optimising our use of water and energy now.
AWER has created a planning tool, the 3C50 model, to assist Malaysia to be water- and energy-efficient. We have started work to help gear Malaysia towards being water- and energy-efficient throughout the life cycle of water and energy.
The "friendship" between water and energy only shows that we are still in the early stage of harvesting the potentials to obtain water and energy sustainably via technology advancement.
Piarapakaran S.President, Association of Water and Energy Research Malaysia,Kuala Lumpur NST Opinion Letters-to-the-editor