The article is very hard to read (I am assuming a bad translator app is to blame) but as I understand it they are claiming 97% solar to heat conversion. Some discussion of how solar thermal efficiency is measured, and some numbers to compare to would help put this 97% efficiency claim into perspective.
A piece of flat black painted steel, or even black paper, will get roughly 95% efficiency converting sunlight into heat. But, as the temperature of the black steel panel increases to something significantly above the ambient temperature the simple black panel "solar collector" will begin to lose energy to the environment (by conduction, convection and radiation), and so the overall efficiency of collecting usable solar energy will quickly drop off. If the black painted panel is placed on an insulation pad and put under a layer of glass the amount of energy lost to the environment will decrease but the cost will go up (and the glass will actually block some of the sunlight from reaching the panel, about 10% loss).
Some solar thermal collectors add vacuum insulation that bring the conduction and convection losses to near zero, so they can operate efficiently at higher temperatures. The next step is to add a selective emissivity coating to the panel to greatly reduce radiation losses (heat radiating from any hot surface through space). This type of solar thermal collector is often built in a tubular form to allow the vacuum envelope to be built with relatively thin glass thereby reducing cost and mass (vacuum tube solar collector).
The type of collector cited in the linked article is a concentrating solar collector. The article claims a 2000+ concentration, which essentially increases the amount of solar energy reaching the collection device (the receiver at the focal point of the mirror) to 2000 times normal solar insolation level. The major issue with highly concentrating solar collectors such as this one is that they need to be extremely accurately aimed (they require a very careful 2 axis tracking system) and they can only focus direct sunlight on the receiver (so diffuse light, which is usable by normal solar collectors, is wasted). If the sky is very clear, with little haze or dust or clouds, then most of the radiation reaching the earth at that location will be direct but, if there is even a bit of haze or dust in the air then much of the available solar energy will be wasted. On a cloudy day this concentrating collector will receive near zero energy while a non-concentrating collector might still receive substantial energy.
So, putting aside the question of whether or not the cited 97% efficiency is even possible (not saying it isn't) that number could only be achieved on the clearest possible day. On average, a concentrating collector such as this will see perhaps 20-30% less energy than a flat plate collector, so even if the ideal maximum efficiency is 97%, the overall yearly efficiency will be significantly lower in any real world environmental conditions.
Concentrating collectors are generally used under 2 conditions: 1. If the collector is PV, and the PV cells are very expensive (as the cost of PV has decreased there is little potential to save money with concentrating collectors). 2. One needs very high temperatures. A concentrating collector can achieve reasonable efficiency at higher temperatures than most practical non-concentrating collectors, but at the cost of complexity and loss of diffuse radiation.
So, bottom line, the 97% efficiency quoted (if true) would only be under the conditions of extremely clear skys (think top of a tall mountain in a desert) and at low operating temperatures. Real world efficiency would much more modest.