Rethinking Heating for Refugees

The average stay in a refugee camp is 17 years, according to the UNHCR, and for many refugees, temporary shelters become permanent homes. In Lebanon there are 1.5 million refugees, with 238,867 refugees living in the Bekaa Valley alone. In the winter, temperatures often drop below freezing and refugees rely on wood burning stoves to stay warm. Feeding these stoves consumes a large portion of refugees’ income and time, and by morning the tents often drop below 53.6 degrees—the World Health Organization’s minimum healthy living temperature.

To alleviate these problems, Ember is designed as a simple, effective, and low-cost thermal energy storage device that captures heat from stove exhaust. Ember attaches to existing wood stoves to extend the time that tent temperatures remain high; thus, energy is more efficiently extracted from the fuel.

A combination of computational modeling and feasibility constraints determined the optimal shape, size, and material of the device. The final product is a hollow cylinder capped by air-tight gaskets and aluminum base plates, filled with low-grade (large-diameter) gravel, chosen for its high specific heat capacity and low flow impedance. Additionally, Ember is designed to consist of locally-sourced materials to reduce costs and increase accessibility.

The design was refined with over seventy hours of testing, and a conservative estimate shows that Ember extends heating time by 150% with the same fuel input. Using economies of scale, the device has been projected to cost $66.77, and will pay for itself in under a year, even without the assistance of international aid organizations.