Dr. Thomas Hinderling, CEO, CSEM on Solar Islands

Building solar energy without subsidies from the Government

One year ago, as a technology incubator, CSEM had founded its 25th start-up in Nolaris. The goal of this initiative was to undertake the design and production of a new solar energy installation: the "Solar Islands".

As the time progressed, the concept of Solar Islands has continued to gain prominence.

In fact, towards the end of the third quarter of this year, it was shared that a prototype of a floating Solar Island, being developed at Ras Al Khaimah for trial, is expected to get completed by the end of this year.

Speaking exclusively with CSPToday.com, Dr. Thomas Hinderling, CEO, CSEM confirmed that the proof of the concept will be attainable at the end of this year.

It was in May last year when CSEM, the Swiss Center for Electronics and Microtechnology, had signed a contract with the Government of the Emirate of Ras Al- Khaimah (RAK) in the United Arab Emirates (UAE), to develop a prototype of a Solar Island. Project partners are as follows: RAKIA (Ras al Khaimah Investment Authority), CSEM (main contractor), CSEM-UAE (sub-contractor), Nolaris SA (sub-contractor), and CEA/Liten - Grenoble (sub-contractor).

The aim of the project is to validate a concept for the large-scale transformation of solar energy into hydrogen and electricity at very low cost. It is being shared that these giant floating islands will be fitted with solar thermal panels, which will convert solar energy into electricity and/or hydrogen.

Sharing information about the entire process, Hinderling said these islands will also carry photovoltaic panels – it just depends on what the customer wants.

"In the case of PV, we propose concentrated PV to bring costs down. The chain is as follows: Solar to electricity, electricity to hydrogen or methane as fuel, the fuel is being transported in tankers as today to be used at the destination. Or: Solar to electricity, electricity fed into the grid. Or: Solar to heat, heat to cool, cool to air condition. Or a mixture of these all," explained Hinderling.

Funded by the RAK government, the $5 million project will first be tried and tested in the desert before it gets launched at sea. The plan is to build large "Solar Islands" floating in the sea. These giant floating islands will be fitted with solar panels, which will convert solar energy into electricity and/or hydrogen.

On how the building of Solar Islands will create a new benchmark in the solar industry, Hinderling said the benchmark will be the cost per kilowatt-hour of solar energy.

"It should prepare for a competitive business in solar energy without government subsidies as in Europe and in the US," pointed out Hinderling.

Venturing into an unknown territory

In September this year, the detailed design of all solar themal modules and all interconnecting parts related to the project got over. And manufacturing and installation of all components had started by then.

But the run so far hasn't been without challenges.

"This is a new territory; nobody ever built something like this. We do encounter many problems, smaller and larger, but so far none of them have been insurmountable," said Hinderling.

He added, "But we do have a delay in regards to the original planning of about four months."

In terms of technology, the circular Solar Islands have a diameter of five kilometers and an height of 20 meters,  consisting of a torus, which is the steam storage, carrying the thermosolar panels placed on a membrane. Electric pumps constitute an overpressure of 0.1 bar to sustain the membrane 20 metres above the water level.

The whole platform adjusts its position to the course of the sun, to assure a maximum yield rate. To enable the platform to move, electric hydrodynamic motors will be fixed every 10 metres along the circumference. The platform can be situated floating on high sea, on remote cost lines and even on shore.

On how this would ensure a maximum yield rate, Hinderling shared that the estimated overall efficiency of large solar islands is in the order of 18 percent – "very high for the low cost approach".

Advantages of Solar Islands

According to CSEM, there will be five times lower cost per kWh than competing systems, because: extremely simple low-cost EFC type panels can be used; alignment is achieved by simply turning the platform (no costly precision mechanics), the active area of panels can be more than 95 percent of the available area; very low sensitivity to wind, so that high up times are feasible; the platforms are hovering, therefore very large platforms can be build; the thermal principle allows to store energy, so energy can also be supplied at night; the active area of panels can be more than 95 percent of the available area.

It is typically near the equator where the solar irradiation is very intense. So water, needed to generate hydrogen and cooling, is available in abundance. Plus, combination with water desalination is easily possible through collection and passive evaporation.

Considering these advantages, Hinderling said: "We do have a cost advantage due to the low inherent complexity of the mirrors - just mirrors, as in your bathroom. No exotic materials, no high energy production processes."

Another positive factor is that the platforms can "follow the sun", gaining 15 percent of efficiency.

"If one is located at a fix location, the sun moves in its zenith 47° between summer and winter. If one can follow the sun, the sun is always at 90° at noon, thus providing the optimal irradiation," said Hinderling.