Hi Marcin,
I'm excited about the solar work you're doing.
Just by way of introduction, I'm an accountant from Sydney,
Australia.   I spent a lot of time the last couple of years looking
into & experimenting with small solar thermal systems.   I basically
went through the kind of steps you did experimenting with parabolic
troughs & Mylar & running into the same problems you did.    I think
glass mirrors are definitely the way to go along with the linear
fresnel arrangement.   I love your use of flat mirrors & your receiver
design.
It's a refreshing change to see someone who is focussed on the
financial viability of solar thermal before getting carried away with
the technology.   I think you're performance numbers are for the most
part pretty realistic.    I did some financial & performance modeling
for some of my experiments with evacuated tube systems.   I pumped
your system's numbers into it.   This is for a CHP residential
application. Thought you might like to see the results.  You can
download the excel sheet here: 
http://www.onlineaccountingservices.com.au/solar/SolarTurbine.xls
Note in particular the seasonal graph.  Here is where one of the main
problems with solar thermal manifests - there is a mismatch between
supply & demand.
Anyway.   Do you have any members in Australia?    I might like to be
involved in some way if you are looking for help.
Regards,
Lee Wright.
On Nov 20, 2:40 am, "Marcin Jakubowski" <
joseph.dolit...@gmail.com>
wrote: