Solar tower in desert promotes Israel’s renewable energy drive
ASHALIM, Israel: In a vast expanse of open desert in southern Israel a 787-foot tower (240 metres) is taking shape that its builders hope will help make solar energy much more cost effective.
The tower, being built by Israel-based Megalim Solar Power, whose shareholders include General Electric, will be taller than other solar towers, enabling it to generate up to 121 megawatts of power.
Due to be completed late next year at a cost of 3 billion shekels (RM3246 million), the facility will provide around one per cent of Israel’s electricity under an agreement with the Israeli government, which aims for 10 per cent of the country’s energy needs to be provided by renewables by 2020.
Most solar power in the world is generated by photovoltaic (PV) panels, which can be installed anywhere from a roof to a backyard. In contrast, towers that use concentrated solar power, known as CSP, require a lot of land and are only costefficient in large-scale projects.
For that reason they have seen limited deployment, and mainly in the United States and Europe.
Megalim’s tower in the Negev desert, which stands out for miles around, is surrounded by 50,000 computer-controlled mirrors, to project the sun’s rays. They are bigger than in previous projects and controlled over a dedicated Wifi network, rather than with expensive cables used in the past, Megalim says.
The tower is privately funded but when completed the Israeli government has guaranteed to buy the power from it at an above-market price.
That means it will be effectively subsidised, but Megalim says it is working to further reduce costs. Shareholders including power tower pioneer Brightsource Energy as well as General Electric, which will provide the turbine, want to build more such towers around the world.
“We’re making strides in efficiency, we’re making strides in compressing the time of construction,” said Megalim’s Chief Executive Eran Gartner. “We’re going down a learning curve that will help us to offer solar energy at the most competitive rates.”
To narrow the gap with PV panels, which make up 95 per cent of the solar market, the USbased Solar Energy Industries Association says CSP needs to reduce hardware costs and to twin its output with an energy storage element that will allow electricity production at night.
Megalim’s tower in Israel will generate heat of up to 540 degrees Celsius (1,000 Fahrenheit), producing steam to drive a turbine. It will not be able to store energy but has overcome another problem that beset solar towers - whether or not power towers were killing large numbers of birds.
When Brightsource built a three-tower facility in Ivanpah, California in 2013 with local partners, some experts said heat from its mirrors would incinerate tens of thousands of birds each year.
A public outcry about the issue was in part responsible for Brightsource cancelling plans to build another tower complex in California.
An official report, based on findings by biologists and teams of dogs that combed the Ivanpah facility, documenting and categorising every bird death, has since shown the impact to be low.