Don't waste money on energy costs! The best way to start reducing those bills is to use the best insulation available, closed cell spray foam insulation.
In 2015 we spray foamed the entire inside of a brand new steel framed semi-tractor and trailer repair shop that C&D had built near Dyersville, Iowa. After the project was completed and periodically throughout the winter we stopped back and spot checked the the walls and ceiling of the facility using our laser thermometer. Throughout the entire winter, with large overhead doors being opened and closed as trucks were brought in for service, the building maintained temperatures above 60 degrees the entire winter... and the owner hadn't even hooked up the new furnace yet!
The number one cause of heat loss is through air loss. With many standard batt insulation, it's is impossible to create a sealed environment in the wall cavities rim joist areas and attics that will completely prevent the passage of air. Stop the passage of air and you will stop the loss of your climate controlled heat and air conditioned air.
We use a closed cell spray foam. Once applied the product forms a very rigid insulation that is very strong. Closed cell does not allow air and water to pass. Additionally, when added to walls and attics, closed cell spray foam insulation actually improves the strength of the buildings structure, acting as a "super glue" of sorts that ties the entire structure together.