This looks like a Jalapeno chili pepper. They do turn red eventually. Growing in a container, as long as you have used sterilized potting soil, is GREAT for peppers.
Your plants aren't looking that great. Sorry, I am used to peppers as annuals not perennials. They look incredible for peppers after 2 years.
What is the light source? I would cut back watering by half. What fertilizer have you used? What soil? How do you water? Every day? What zone do you live within and where does this plant live? Out of doors or indoors?
I am thinking you've used a fertilizer that is too high in nitrogen versus the phosphorous and potassium. Lots of flowers, no fruit. Your plant looks as if it gets plenty of nitrogen and has a healthy green.
Too much nitrogen in relation to the phosphorous and potassium promotes vegetative growth not reproductive growth. I find it interesting that you have a lot of flowers but no fruit.
What are you doing for pollination? If indoors and/or during the winter you won't be having any insects helping with pollination. You will have to manually pollinate...mostly just shaking the plant from time to time will pollinate those flowers. Artist paint brushes work well.
Please tell us more about this plant's environment, your maintenance habits, the fertilizer you've added the soil you used in this pot...