When shopping for thermostats, look for the Energy Star listing this is a listing that the thermostat meets minimum standards to reduce the energy usage of the Heating and A/C systems.
Programmable thermostats basically maintain your homes temperature based on your expected occupancy. However this advantage is also their shortcomings. They don\’t know when you will be late coming home, or when you go shopping for the day, and is still heating the home thinking your are home.
Communicating thermostats are capable of knowing your true occupancy based on your security system. Your security system when used know if you are home, away or even sleeping based on its armed status. This is true occupancy based HVAC control.
When selecting your heating systems there are better choices than just looking at efficiency standards.
Radiant in-floor heating is considered the most efficient and least expensive to operate, but comes at a higher cost of installation.
Heat pumps are considered the next best as it gives heating and cooling, often they are ground sourced to preheat or pre cool the system with the earth core temperature around 60 degrees. This offsets the need for artificial heating and cooling.
Also planning your homes natural radiant heating with your system will help reduce the costs. Turning on your systems fan prior to the actual cooling will often reduce the need or time of the cycle but circulating the heat pockets of the home to even out the overall temperature. Using Shade controls can help with this as well by reducing the radiant heat in the summer or increasing them in the winter.