Case Study Home # 6
Geo-Solar Passive House
Geo-Exchange Basement Energy

Annapolis, Maryland

 Basement Encapsulation

Annapolis has the world's first Earth or Geo-Ventilation, "Basement Energy" system. After months of research the first prototype began development in winter of 2010 and by the fall of 2011 the plans were underway to install the first system in the Bardwell Residence. Just completed in the fall of 2012, the first installation of its kind using this patented energy system confirms this system as a new viable energy source. Realized through collaboration between a genius-builder, inventor-scientist, and a visionary architect, this geothermal system is pending 30% federal energy tax credit approval for all associated cost of the energy system. 

After years of development the creators met at the gutted remodel of the Bardwell construction project to plan the first application of the Basement Energy System. When they left the dwelling, they shared the same enthusiasm similar to that of young pioneers about to navigate uncharted territory. Together they developed a new system utilizing the basement slab and foundation walls for geothermal energy transfer and storage. Geo-thermal or “Geo Ventilation,” in a nut shell, uses the earth to provide cooling and heating, by ventilating a basement structure that has been encapsulated with air tight insulated panels creating the “Geo Cavity.” 

Do you remember going down to a basement, experiencing how it smelled, and how it felt.

What I remember was how dramatically cooler in the summer and warmer in the winter it was.

Before now, the Passive House industry has abandoned the basement, recommending keeping it out of the thermal living envelope, due to moisture liability reasons.

Now with our system, we take full advantage of the earth’s contributions, by encapsulating the walls and floor of the basement, therefore eliminating hostel contaminants, such as:

  • Radon
  • Mold / Allergens
  • Moisture
  • Odor

This system creates a cavity extracting air that is conditioned by the basement structure, therefore removing all of the contaminants, and the air become the subterranean / geothermal temperature.

This contaminated air leaves the home through an “air-air” heat exchanger (ERV) and exchanges temperature with the fresh air coming into the home on a 24/ 7 basis.

For example, in the summer the incoming 95 degree outside air for the cost of electricity for a 60 watt for a light bulb, becomes the temperature of the earth (approximately 58 degrees), and in the winter 10 degree in-coming outside air, become the temperature of the earth (approximately 54 degrees). The final benefit is that we are removing all of the contaminants of the home envelope, and replacing with fresh air 24 / 7. We recycle with a second ERV the exiting (house temperature) air and exchanging with the fresh incoming air, within a few degrees of the desired living temperature. All of this is done with the fan power equivalent cost of just two 60 watt light bulbs. 


  • So a properly insulated Passive House Retrofit with Basement Energy Panels accomplishes:
  • Removal of contaminants and results in a allergen free environment
  • Brings in twice filtered fresh air 24 / 7
  • Creates a constant temperature throughout the home from basement to the uppermost level
  • Reduction of the utility cost up to 90%