Burning wood can be an attractively cheap source of heat from sustainable biomass. It can also be nice and cosy on cold winter days to curl up with a book in front of the old fireplace. However, as always, it is important to become well informed before committing to getting a large portion of home heating from a wood stove.
The economics and sustainability of wood burning varies substantially based on the type of stove and the type of wood used. A highly efficient stove burning fully dry recycled wood wastes can give you clean, safe and economical heat under any weather conditions, but an old inefficient design burning improperly dried or unsustainably harvested wood is much less sustainable and economical and can even be dangerous.
A good modern wood stove can be substantially cheaper to install than a gas furnace or a heat pump and has similar fuel costs (in the US at least – might be substantially cheaper in Europe where electricity and gas prices are much higher). In addition, a stylish wood-stove makes for a very attractive living room centrepiece. A good stove is also long-lasting, very simple to operate and maintain and completely invulnerable to any power outages or gas supply disruptions. These are some very attractive advantages.
However, a low-quality wood stove or a high-quality wood stove burning low-quality wood can present several problems. Firstly, fuel consumption is significantly increased, thereby degrading the attractive economics of wood burning. More importantly, however, low-quality stoves and/or wood produce a lot more particulate matter which can pose a health hazard both to yourself and your neighbours. Particle matter also causes buildup inside your furnace and chimney (requiring more regular maintenance) and creates smoke which spoils the splendid view of a clean-burning flame in your living room.
The figure below gives some indication of particle generation from wood stoves. Although particulate emissions from a high efficiency EPA certified wood stove remains much higher than that from a gas furnace for example, it is sufficiently low to not pose any significant hazard.
Regarding the wood, it is most important to ensure that your fuel is as dry as at all possible. Even slightly damp wood can completely spoil the efficiency of a good wood stove, substantially increasing fuel usage and particulate pollution. Generally, newly bought wood should be left standing in a dry place for at least one year before it is fully dried out. A little bit of longer-term planning is therefore important in managing your wood stockpile.
However, the best fuel for your wood stove is most often compressed sawdust blocks. These blocks might work out slightly more expensive than standard firewood, but, aside from their obvious environmental benefits, they also offer a higher energy density, easy stacking/storage and the added advantage that they can generally be bought bone dry. These properties make compressed sawdust bricks ideal for simply ringing up your local dealer and filling up your basement with neatly stacked recycled biomass whenever you run out.
All in all, a high quality stove burning smartly selected wooden fuel is a great choice for environmentally friendly and environmentally sound heat. If you live anywhere where it becomes slightly cold, don’t hesitate to acquire one of these.
Filed under: Consumption patters – The green economy