When building your new home you are going to have a lot of choices to make in energy efficiency. The choices you make here will affect your heating and cooling expenses for many years to come.
During construction, insulation in the walls and ceiling is normally the first consideration. Even before we get to this point of construction, you can improve the energy efficiency of your home.
After the framing is completed, use of exterior insulating sheathing instead of plywood can have a noticeable effect on the R-value of your wall insulation. If you chose 2x6 framing instead of 2x4 framing for the walls, now you can use an increased thickness of fiberglass batts or rigid foam insulation for a higher R-value.
For your roof, a radiant barrier can be installed between the roofing material and the insulation, to reflect the heat back up toward the roof, rather than directed downwards towards your ceilings, which makes your A/C system work that much harder.
For your ceiling insulation you would be better off going with blown-in rather that batts. The problem with batt insulation is it does not fill in gaps and cracks very well, therefore some areas of your ceiling will not have any protection. Blown insulation will give you a good complete layer of protection. The depth of blown-in material will determine the R-value, so an accurate determination of this is needed.
A third option for ceiling insulation is spray foam. This seems to be a better choice, but will be more expensive than either batts or blown-in insulation.
Next on the list will be energy-efficient doors and windows. These can add considerably to the home's energy efficiency. Pella and Anderson carry some beautiful energy efficient windows for your new home. Of course the initial cost is higher than contractor quality products, but the end result will put a smile on your face every time you come home, or look through your windows from inside your home.
The more energy-efficient your home is designed, the less work the HVAC unit will have to do to provide you with the same comfort level inside. Therefore a smaller HVAC unit can be installed, thus reducing your initial home construction cost.
After construction, the appliances you install such as refrigerator, freezer, water heater, stove/oven, television, dishwasher, can continue with your plan of energy efficiency. The list goes on and on. Choose your appliances based on the energy efficiency rating of the equipment, for a greener household.