Did you know that in olden days when it was cold outside and people could not afford more insulation, they used heavy curtains to keep the drafts out?
They were used around beds, near doors, and windows.
They were also used to block out rooms that were not being used in the winter to keep the heat in the rooms that were being used, so as to not have to heat empty spaces and waste the energy.
Now the same applies in the summer when you want to keep the cool in. Putting curtains in the window (usually light in colored for the side that faces the window which repels the heat) have a way of keeping the mid-day sun out and keeping the rooms cooler although darker. Not a problem if you are at work all day. This can decrease your air conditioning bills.
The only thing with curtains is that they have to be of the heavier variety. Flimsy lacy curtains won’t do and for some it represents a fashion faux pas.
However, if you look in most hotel rooms, you will see they have 2 sets of curtains. Usually a sheer one and one pair of the heavier sort and this is how they get over that decorating problem.
In my quest to see if they actually promote these older than time methods of insulating against the heat and cold I went online to see if they actually promote these curtains. Low and behold they do. And the reviews are great.
Mind you, if you have an eye for it you can probably go to the local second hand store and fashion your own.
You can also have shades or I’ve read people using bubble wrap on windows. But I can leave those exploits to you!