As we observe World Water Day (WWD) on March22, 2010, it is useful to reflect on the connection between water andenergy.
First, some background on World Water Day: It is a United Nations event thatbegan in 1992 after the Earth Summit in Rio de Janeiro. Each year theU.N. highlights one or more issues relating to freshwater supplies andquality. This year the U.N. chose Clean Water for a Healthy World as its theme. The overall goal of the World Water Day is to raise theprofile of water quality at the political level so it is consideredalongside decisions regarding water supply.
While the technology sector is very focused on energy, the nexusbetween energy generation, use and water is not generally recognized.Here are some relevant facts:
- Electricity production requires about 136,000 million gallons offreshwater per day, accounting for over 40% of all daily freshwaterwithdrawals in the United States.
- Texas power plants use over 157,000 million gallons (482,100acre-feet) of water annually - enough for over 3 million people for ayear, each using 140 gallons per person per day.
- In many regions of the U.S., we indirectly use as much water turning on the lights and running electric appliances each day in our homes aswe use directly in taking showers and watering lawns.
- The energy required to move water from its source across varyinggeographies, to then treat the water and finally to convey it to usersis also enormous. The single biggest energy use in California is thewater projects (State and Federal) that consume nearly 12% of theState’s electric energy.
- In North America, approximately 90% of wastewater is treated; inEurope the figure is 67%; in China, a little less than 40% is treatedbefore discharge. In developing countries, however, 80% of all waste isdischarged untreated, because of lack of regulations and resources. Andpopulation and industrial growth add new sources of pollution andincreased demand for clean water to the equation.
The environmental footprint of many products is being evaluated today in terms of "embedded carbon", meaning the amount of greenhouse gasesassociated with the production of the good or service; in most instances a significant amount of the embedded carbon is due to electricityrequired to make the product. "Embedded water" or the amount of water required to make a product is alsobeing examined and the results can be eye-opening, e.g. a kilo of eggshas 3,300 liters of embedded water, a pair of jeans 10,850 liters and an automobile 400,000 liters.
Water is already an extraordinarily stressed natural resource, asthose of us in California know all too well. While carbon dioxide (CO2)has in some ways become the surrogate metric for overall environmentalimpact, it is important to consider other dimensions as well, not onlyin terms of business decisions, but also in terms of lifestyle changes. So, when you turn your light on to read your favoritebook, pause for a moment to think about all the resources used to makethat little lamp burn so bright.
Image courtesy of the U.N.