80% efficient wood stove?

Can a wood stove be efficient? Is there a way to increase the efficiency of a wood stove?

Not everything in our house is high-tech. For those cold winter days that are neither sunny nor windy we have to have a low-tech method to warm up the house.

Just because a wood stove is considered low-tech it doesn't mean that it should be inefficient. We started with a Morsø stove that was 71% efficient (test according to Autralian Standard 4012) and improved its efficiency by installing a non-standard flue.

The long and non-vertical stainless steel flue helps to cool down the hot fumes before they fly away, and hence helps to retain more heat from the burned fuel in the house interior.

This is especially noticeable when we start the fire. While the firebox is still cool to touch, the flue radiates plenty of heat.