'New water economy must check energy demand'

In 18 months, desalination will provide enough water for 80% of Israel’s urban drinking needs, experts say at CleanTech symposium.

By SHARON UDASIN
Desalination plant in Hadera 311 (R) (photo credit: REUTERS / Nir Elias)
Desalination plant in Hadera 311 (R)
(photo credit: REUTERS / Nir Elias)
As the Israeli water management and treatment industries continue to grow, it is crucial to ensure that all facilities operate with maximum efficiency, to prevent the loss of valuable energy, experts agreed at a conference at the Tel Aviv Fairgrounds on Tuesday.
Water professionals and government officials were speaking at the Energy-Water Nexus Symposium, held within the CleanTech 2013 – 17th Annual International Summit and Exhibition.
“Israel is emerging from times of crisis in the area of water into stability,” Energy and Water Minister Uzi Landau said. “We have no only continued what has started in the past to develop desalination plants, but we are now building new and we have extending and developed those that already exist.”
With those developments, however, come large energy requirements to power the desalination plants and sewage treatment facilities that are changing the face of the Israeli water economy.
Operating energy production plants also involves the use of plenty of water, the experts explained.
“It is clear to everyone that there is cross-influence between energy and water,” said Oded Distel, director of the Investment Promotion Center at the Industry, Trade and Labor Ministry and head of the Israel NewTech program there.
Distel went on to add agriculture and food security to that synergetic list, saying that with every project in any of these categories, entrepreneurs must take under consideration the effects the plans will have on all of the other components.
“The solutions are there to meet our water needs,” said Dr. Glen Daigger, president of the International Water Association and senior vice president and chief technology officer of US-based water firm CH2M HILL.
“The issue is that in many of those it takes more energy to produce that additional water in different ways,” he added.
While population growth, higher living standards, climate change and urbanization across the world have contributed to a “global water crisis,” solving that water crisis must occur in an environmentally friendly way, with a reduced net amount of energy consumed, Daigger said.
Israeli water pumping used 3,200 gigawatt-hours in 2012, with 1,830 of these gigawatt-hours being consumed by Mekorot National Water Company pumps, said Dr. Yigal Kadar, manager of Mekorot’s energy department.
While 3,200 gigawatthours may seem small compared Israel’s total annual electricity consumption of 57,100 gigawatt-hours, the amount consumed by pumps is expected to rise to 10,700 gigawatt-hours by 2050 as water needs increase, Kadar explained.
The company is therefore continuously seeking methods to improve pump efficiency and make sure its more than 3,000 pumping units have good energy performance, he added.
Although many people criticize the increased deployment of desalination facilities due to their heavy energy requirements, the effici ency of these facilities can be improved with large, energy- saving pumps, according to Prof. Rafi Semiat, dean of chemical engineering at the Technion-Israel Institute of Technology in Haifa.
In the early days of desalination on cargo ships in the 19th century, evaporation of water consumed about 650 kilowatt-hours per cubic meter, but at today’s Ashkelon facility, reverse osmosis mechanisms require only about 3.5 kilowatt-hours per cubic meter, Semiat said.
In about a year-and-a-half’s time Israel will produce roughly 600 million cubic meters of desalinated water per year, covering about 80 percent of urban drinking water and requiring about 1.36% of the country’s energy supply, Semiat explained.
Today, about 40% of energy consumed here goes to electricity, 43% to fuels, 13% to Palestinian needs and 3% to solar water heaters, he said.
“We can invest in more equipment, more membranes to reduce the pressure we are working in,” he said of desalination processes, noting, however, that this would be expensive.
“You have to remember one important point – water is still the cheapest product on Earth,” Semiat continued.
“And still there are people who claim this is too much for them, and they are right.”