Energy performance of Portuguese and Danish wood-burning stoves

In Europe, considerable amounts of renewable energy resources are used for residential heating with wood-burning stoves, which can cause considerable energy losses and environmental impacts. A better understanding of its operating characteristics will permit to improve the buildings energy efficiency and indoor climate, and to reduce the emission of air pollutants to the environment.

This study aimed to analyze the operating conditions of a Portuguese made stove and compare it with the most efficient Danish made stoves tested at the Technological Institute.

The combustion experiments were carried out through the measurement of the main operating parameters: flue gas temperature and composition, combustion air flow rate, and fuel consumption rate. The results showed that the appliances emitted energy intermittently, with a mean heat flow rate into the indoors of 5 kWth, representing mean thermal energy efficiencies of 70% and 76%, respectively for the Portuguese and Danish stoves. The Carbon Monoxide concentration in the flue gas was lower than 0.4 % (v/v; 13% O2) for all stoves.
There is still a need for more accurate knowledge the relationship between the energy and the environmental performance of the appliances. A dynamic analysis of the problem will permit to increase the households energy savings.