Energy and Comfort Assessment of Mongolian Ger Dwellings
"I was born in a ger, I grew up in a ger, I got married in a ger. I have never lived in a house. I love my ger.” (Tagtokhbayar Tuvaan)
Working with the Mongolian non-profit GerHub, PennDesign’s Center for Environmental Building and Design is auditing the comfort and energy use of a selection of buildings in the ger district of Ulaanbaatar to understand their thermal behavior and to identify opportunities to improve both their comfort and energy performance. The team has also assembled a ger at the Pennovation Center, where they can study its behavior in more detail and more readily test improvements.
Ger are the traditional, tent-like dwellings of the Mongolian herder nomads (called Yurts in Russian). With the steady urbanization of Mongolia since the 1960s, former nomads have been settled in legal, semi-formal “ger districts” at the perimeter of cities, and roughly 60% of the residents of the capital city live there in a combination of ger and self-built rigid frame houses. Ulaanbaatar is the coldest capital city in the world, and almost all of the 200,000 ger area households burn unrefined coal, making it one of the most polluted cities as well. Beginning in 2009, the World Bank and Millennium Challenge Corporation funded a program to provide more efficient stoves to the region, a program which has mitigated coal use and pollution to some degree, however there is little information on thermal characteristics of the ger construction itself, either in terms of energy use or the connection to interior comfort, clothing, or lifestyles.
The climatic conditions in the region are extreme. According to the Millennium Challenge Corporation, “Mongolia has an extremely harsh winter climate, and mid-winter temperatures in Ulaanbaatar, the capital, can drop to as low as minus-40 degrees. Nearly half of all Mongolians live there, the coldest capital city in the world and the world’s second-most air polluted city." Ger are only kept warm in winter with a steady supply of fuel (wood and coal). They are a lightweight form of construction with little capacity to retain any heat, so the thermal properties of the envelope construction and air sealing are critical to their energy use. The question of interior comfort is equally important and the interior temperatures are limited by the leakiness of the envelope and the firing cycles of the stoves. With the installation of the new stoves “rebound effects” have already been noted: occupants maintain higher interior temperatures once the new stoves are installed, effectively spending the savings of the more efficient stoves. Real energy savings and pollution reduction can only be achieved by making residents more comfortable with less fuel consumption.
The immediate result of the project will be an auditing protocol for Mongolians interested in evaluating and improving the energy performance of their ger. The longer-term project is to collaborate with the many parties in Mongolia working to develop improved ger, better adapted to their fixed, urban locations. The ger is deeply bound up with Mongolian nomadic culture and identity, so any projected improvements will be developed in close consultation with ger residents and carefully balance the symbolic value of the ger with the metropolitan conditions of the ger district.