...IN A SMALLER, MODULAR HOME.
When comparing energy savings between a truly functional and a standard size home, there are several factors to consider. A smaller home is cheaper to heat & cool since, you guessed it, it is a smaller space. Truly functional homes, particularly those designed with energy efficiency in mind, can offer significant savings:
Superior insulation and air tightness: The difference between average insulation and the best insulation is around $2000, but remember that your power bill will be about 30% less each month for the rest of your life. This means that after about 3.5 years, you should be saving money 
Passive House Standards: We strive to build passive homes. We wrote a full article on that here. Passive homes can improve heating/cooling in new homes by 90%. Yes, NINETY percent
Reduced overall energy consumption: Due to their smaller size, truly functional homes generally have lower overall energy consumption compared to standard size homes. Truly functional homes use about 7%  of the amount of energy it takes to power electricity for an average size house. That is huge
So, let's say you're spending about $170 a month on heating, cooking, lights, and misc. other power users in your home. That's about $2040 a year. By moving into a truly functional home you would spend about $140 a year on power. That's a savings of $900 a year. You know what that is? That is a nice Lectric Lite eBike!
Energy-efficient truly functional homes can provide substantial energy savings when compared to standard size homes. Factors such as superior insulation, energy-efficient building materials, adherence to Passive House Standards, and reduced overall energy consumption contribute considerably to these savings.  https://thetinylife.com/tiny-house-insulation/  https://tilen.space/how-much-power-does-a-tiny-house-use