If you have used solar water heaters, you will know that you can at best get about 70 deg C (about 160 deg F) from it.
However, some simple innovations and tweaks made to the traditional solar water heater technologies can take the temperatures to about 100 deg C, and in some select cases, these have been able to get the temperature to even about 120 deg C, thus making these systems applicable even for some industrial and commercial heating uses.
Most of these tweaks essentially involve making the heat capture fluid to travel a longer distance than in conventional solar water heaters, thereby enabling them to increase their temperature to something higher than what conventional ones can.
Now, there are companies that use concentrators to heat water to even higher temperatures. In these systems, suitable curved reflectors concentrate sun’s heat on to the heating fluid, this providing it much higher temperatures. Note however that these systems are more complex than simple solar water heaters, and more expensive too, and as a result might not be suitable for small scale solar water heating applications.
One of the companies I have known for a long time uses evacuated tube solar collectors. Using a proprietary design, this company has been able to achieve up to 120 deg C, and they have been fairly successful in their installations in sectors such as automobiles and textiles.