World's highest solar tower looks to future
ASHALIM, ISRAEL — In the middle of southern Israel's desert, engineers are hard at work building the world's tallest solar tower, reflecting the country's high hopes for renewable energy.
Once completed in late 2017, the Ashalim Tower will rise to 240 meters, taller than Paris's Montparnasse Tower and London's Gherkin, according to the Israeli government and the consortium building it.
Covered in stainless steel, the square tower in the rocky Negev desert with a peak resembling a giant lighthouse will be visible from dozens of kilometers away.
A field of mirrors covering 300 hectares — the size of more than 400 football pitches — will stretch out from its base, directing sunlight toward the tower's peak to an area called the boiler, which looks like a giant lightbulb.
The boiler, whose temperature will rise to 600 degrees Celsius (1112 Fahrenheit), generates steam that is channeled towards the foot of the tower, where electricity is produced.
The construction, costing an estimated 500 million euros ($570 million), is being financed by US firm General Electric, with France's Alstom and Israeli private investment fund Noy also involved.
Israel's government launched a tender for the project in 2013, committing to purchase electricity from it over 25 years as part of a shift towards renewable energy and energy independence.
The country mainly generates electricity using plants fired by coal, natural gas and fuel oil. Its domestic supply of natural gas has grown with the discovery of fields in the Mediterranean.
Solar requires a major investment, though costs are gradually coming down.
Energy from a solar tower is "two to three times more expensive to produce than classic electricity plants using carbon or fuel," said Eran Gartner, who heads the Megalim consortium managing the project.
The tower should provide 121 megawatts, or two percent of Israel's electricity needs, enough for a city of 110,000 households.
The country of eight million people is seeking to make renewable energy account for 10 percent of its total consumption by 2020.
Solar power offers a clean alternative to fuel- and carbon-fired electricity plants, which contribute to global warming with their heat-trapping CO2 emissions.
Israel could in theory meet all its electricity needs through solar energy by using only four percent of the Negev desert, said Eitan Parnass, head of the Green Energy Association of Israel.
Israel's offshore gas finds are a major boost toward energy independence, but Parnass said it must continue to diversify to avoid reliance on a single source in the turbulent Middle East.
"Israel has no choice but to diversify its energy independence, first for reasons of security."
However, critics have panned the project as too expensive and complex compared to other solutions.