Making a conservatory useable all year round

[Travelcrazy]

We are looking at buying a house with this conservatory but we will need to be comfortable in it all year round because we will be using it as a dining room and I would need to be be working full time in there.
It only has a single door and three small top opening windows so I am concerned I will cook! It is a south facing garden.
Is there a way of keeping it cooler in summer and will it be massively expensive?
My Dh has said that he can put bigger radiators in so it should be ok in winter.
Thanks for any help.

I wouldnt change our glass roof, love looking through it. Its self cleaning, I didnt believe that, but it is. It doesnt rain a lot in the summer though, it does it itself when it rains.

How old is yours? I wonder if that makes a difference?

I think it might be about 7 years old, would need to check. Might be more, time goes very fast!

Oh I just checked, yes 7 years ago this month it was put up