The reason I ask is for energy saving and a assume the light from the sun is the best form of light for any reptile?
Hi Darren,
Yes. sort of.
But only if your animal is outside in a properly set up (and amply shaded) cage.
Sunlight through a window *can* give you good "general" light...
but guess what... ?
ALL the UV is filtered out by the glass.
So if you are thinking that you can have your pet in front of a window like a potted plant... and it will live and thrive with no regulated heat/basking light or proper levels of UV....
I am sorry to say that you will kill it.
Sorry to be blunt...

..
so please forgive me.
It is just because I care about this.
I must emphasize the seriousness of creating a PROPER ENVIRONMENT for these delicate tropical animals.
A Cham plunked inside in front of a window...
probably will have trouble thermo-regulating and digesting its food,
just for starters.
Especially if the sun only comes through a short time each day.
Because that will not be enough to create a proper, controlled heat basking spot so they can thermoregulate and digest.
(OR - you will get TOO much and cook it.

)
If that doesn't "do it in" first....
then it will just end up with MBD from lack of UV anyway.
Get stunted, deformed and crippled and and die a horrible death.
But there is good news!
If you do a search here - you will see you can use proper UV lighting and a basking spot over your free range animal and they can live a long happy life.
And be near a window to enjoy some "natural" (be it with filtered out UV) day-light.
Think:
Create an Environment that it has access to and can CHOOSE its own correct UV and heat/basking levels.
Good luck and use the knowledge in this forum wisely and ask questions & you will have a wonderful long lived healthy pet!
Cheers!
Todd
oh BTW... *sigh*
reptiles are not an "energy efficient" hobby.
I once calculated once I have probably spent over 40,000.00 on electricity keeping animals alive. (reptiles, reef tanks, birds etc. etc.)
I am not saying that's a good thing- Talk about big carbon foot print!
ugh.