Lovins GreenHome 1.0

This case study examines 'Lovins GreenHome 1.0', a residence and headquarters for the Rocky Mountain Institute (RMI) completed in 1984 in Snowmass, Colorado. The home serves as a demonstration of 'Factor Ten Engineering' (10xE), an integrative design approach that prioritizes functional goals and passive systems over conventional HVAC installations to achieve radical resource efficiency.

• The Lovins GreenHome 1.0 achieved significant resource savings compared to a conventional home of the same vintage, including a 99% reduction in space heating energy, a 90% reduction in electricity use, and over 50% savings in fresh water consumption.
• The home eliminated the need for a traditional furnace and HVAC system by integrating superinsulation, thermal mass, and passive solar gains. The design uses 16-inch thick steel-reinforced walls consisting of two six-inch masonry courses sandwiching four inches of polyurethane foam, providing an effective insulation value of around R-40.
• The residence utilizes 'superwindows' to harvest solar heat and minimize loss. The original windows had an R-value of 5.3, which was later upgraded to 12.5. These windows replaced traditional aluminum spacers with steel to reduce conductivity by over 80%.
• A central vaulted atrium serves as the heart of the home, collecting solar energy through photosynthesis, visible light, hot air, hot water, and heat stored in soil and water. It includes a 900-square-foot garden and uses a 'stack effect' via vertical windows and high vents to cool the building on hot days.
• The home employs passive solar appliances, including a solar-heated water system that pre-warms water in the greenhouse before active solar heating, and a passive clothes-drying closet that uses dark-colored walls to absorb sunlight and a heat exchanger to recover heat from moist exhaust air.
• Specialized appliance innovations further reduced energy use, such as a refrigerator using an external 'cooling fin' (heat pipe) to release waste heat into the ambient air, which allows the compressor to remain off during the colder half of the year and reduces electricity use to 85 kWh per year.
• From a financial perspective, the integrative design approach resulted in a net construction cost increase of only 1% (approximately $4,944 in 1983 prices). The investments in energy savings had a half-year payback period, saving at least $10,254 in annual energy costs.

APA

Yi, A., Ramirez, S., Bendewald, M., & Pradhan, A. (2010). Lovins GreenHome 1.0. RMI. https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_2010-15_LovinsGreenHomeCase.pdf

Chicago

Yi, Aris, Samuel Ramirez, Michael Bendewald, and Alok Pradhan. Lovins GreenHome 1.0. RMI, 2010. https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_2010-15_LovinsGreenHomeCase.pdf.

Wikipedia

{{cite report |last1=Yi |first1=Aris |last2=Ramirez |first2=Samuel |last3=Bendewald |first3=Michael |last4=Pradhan |first4=Alok |title=Lovins GreenHome 1.0 |publisher=RMI |date=August 2010 |url=https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_2010-15_LovinsGreenHomeCase.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{yi2010lovins, author = {Yi, Aris and Ramirez, Samuel and Bendewald, Michael and Pradhan, Alok}, title = {{Lovins GreenHome 1.0}}, institution = {RMI}, year = {2010}, month = aug, url = {https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_2010-15_LovinsGreenHomeCase.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }