how to simulate a net-zero energy round house

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Are you looking for annual energy use, design for load calculations, or both? How accurate do you need it to be and will the outcome potentially be used for code compliance? This website lists software you can use: http://www.buildingenergysoftwaretool..., including free/public tools. This forum is heavily focused on EnergyPlus/OpenStudio which may be overkill for your application. The benefit of EnergyPlus compared to other tools for your application would be decent ground heat transfer modeling.

I am looking for both annual energy use and load calculations. Accurate enough to provide useful information. It will not be used for code compliance. This is for my personal use to better design our future house.

Unfortunately, I am not familiar with any of the software tools of EnergyPlus. Would someone that is knowledgeable about these tools know if this can be easily done?

thanks,