whynot? as you are stopping the light coming in, so see no reason why they shouldnt work.
and dutains are no brainers, and require little effort. just need a largeish area to lay the material out before sewing, and a couple of hours childfreee to put it all together.
hows your conservatory today?
when i did my curtains, i found it easier to lay it all out on the living room floor, and did running stitch all round. that way i didnt have to worry about the material moving. but then i was putting two layers together. im not sure what you are planning tbh. also, i put the sewing machine on the floor, and sat on the floor,so eased the heaviness aspect.
could you do that?