Unfortunately can't do a light tunnel. I think I may have come up with a solution which gives space back to the kitchen and keeps it light. Simply create a 45 degree wall from near the tall unit to the other utility wall. This way, it opens up the kitchen a bit, and lets the light come through a frosted glass utility door.

I am guessing you are thinking of these going into the conservatory roof. They can be effective but the light is directed down. See if you can get a longer pole for the curtains so that they sit back against the wall and not across the glass panel. If you also get a larger mirror over the fireplace this would again increase the light. I cant see the end of the room and whether you have windows at that end as well or if this your only light source.

Thanks minnie101, I was considering putting a mirror on the wall adjoining the window wall, to bounce light back into the hallway which is opposite. Would that work or would an additional mirror be a good idea too? I've attached a quick scribbled pic. :-) Thanks

Hi, stacey -- the layout is of course the first thing to get right, following that you can mimic daylight by hiding the light sources in both the cabinets and around the edges of the room -- layering the light is key, so that you don't have just one bright source. Luckily LEDs these days don't cost the earth! It will be important, however, to create the places in which to hide the light sources, which may mean making adjustments to walls and ceilings....