I still had Habanero peppers on the plant that weren't ripened when the weather started to get colder. The peppers will continue to ripen off the plant as long as it started the ripening process. 

How to ripen peppers off the plant: Remove the peppers off the plant. Put them in an area where they will get sunlight like a warm windowsill or under a grow light. I put these under my grow light in my indoor greenhouse. You want the area to be warm indoors around 65F-70F. Our Apartment is set to 69F (NICE) and have the heat on in the winter so they get nice and toasty. You don't want to put them in the fridge otherwise the ripening process will stop. They need heat to ripen. 

You can see they started to change color and ripen. The full green one might not ripen, but I will wait and see. I don't really know what a green habenaro tastes like. Probably more like a green pepper with some spice or unripe jalapeno where it definitely tastes "green"