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Renewable Energy: We have mostly willow - furnace v range cooker with boiler?
We need to install a new heating/hot water system as we renovate our house. We are trying to figure out the best option for us. We have about 12 acres woodland - there is a certain amount of oak/birch/chestnut but not a huge amount, the majority is previously coppiced willow and some poplars.
I guess the ideal system would be a wood chip boiler but these are so much more expensive plus we would need to house it in an outhouse, buy a serious chipper etc. We would prefer to be able to burn logs (albeit thin ones) if poss.
We would like if poss to get a rayburn/esse (or open to any other suggestions) with a boiler to supply hot water, underfloor heating in 2 rooms and poss rads for a couple of other rooms (which are 2 floors up in our tall house - we have very high ceilings).
Anyone got any experience or knowledge of whether poor quality wood such as willow is ok to burn in a kitchen range or whether you are better with a big boy furnace? Thanks Mandy
'Poplar gives a bitter smoke, Fills your eyes and makes you choke.'
As the old saying goes!
Poplar & willow are both woods with a naturally very high water content, chipping and drying is probably the very best option for them and the chestnut too.
Birch burns very fast and hot, like cypress, so is good for getting fires going but difficult to get a controlled burn. Chestnut also needs drying for a long time and is a bit explosive when it burns. Only Ash is better than dry Oak as firewood (willow is secong only to oak in terms of it's wildlife value!).
We have an esse w23 wood cooker which has the central heating back boiler. The stove will certainly burn your poor quality wood very effectively and produce sufficient heat for the number of rooms you are looking to heat however do use a plumber who is used to installing a wood burner with an accumulator tank as the principle of heat storage is totally different to that used for a gas or an oil boiler. The secret after 9 months of hell with this stove is to use timber with a moisture content of less than 20% . That is not dry wood it is very dry wood. Anything higher and the stove produces tar and creosote which has to be cleaned out which is the achilles heel of the stove. For a full description of the inventivness of w23 owners go to the country living forum and the section just on the w23 stove.
Thanks for comments. Renewable John that is really helpful, thank you. I must say I am quite keen on the Esse plus they are sold here in France and I believe qualify for the 50% tax credit we can get here. Ill mosey on over to the country living forum.
Renewable john gives wise advice. Dryness is more important than species. You will need to season outside under a roof but without walls(possibbly pallets on the rainy side) for at least one summer and preferably two, then bring into a warm outhouse. Remember all wood absorbs moisture from any damp atmosphere, so merely keeping it out of the rain is only half the battle. Best remove from shed to warm outhouse at the end of a long summer dry spell. On no account leave it beyond early Sept. That said, poplar is a poor firewood, and tends to smoulder, so avoid. You will find that water content, size of logs and species make combustion control difficult. A constant combustion + heatstore is a much better proposition than varying the burn rate. Very difficult to entirely eliminate clogging chimney, so make sure the flue can be easily cleaned. Recommend you consult a chimney sweep before commiting yourself.
PS: Stanley stoves (now owned by aga/rayburn I think) have a long satisfactory history in Ireland as farmhouse wood burners in Ireland, tho I have no personal experience. Certainly you should check out.
Do you specifically want a cooker? I understand that a Finn Oven or masonry stove is the most efficient mean of burning wood. They use short, very high temperature burns to heat up a big lump of thermal mass which releases heat into the home slowly rather than roasting you for a short period. Can incorporate a back boiler to heat water and an oven for cooking. The high temperatures result in the combustion of a lot of the nasties that would otherwise go up your flue and into the air. Since you require a short burn only, thin sections of wood are ideal.
Hi thanks. Chris no not 100% necessary for a cooker. Originally we were looking at a furnace to be housed in an adjoining building ... they are just so blinking expensive. Then we just sort of arrived at the thought of hey, why dont we go for a range then and have the bonus of being able to cook. We would have to have a secondary cooker anyway for summer and also for a grill! Cant live without me grill!
Ive seen masonry stoves but not a Finn Oven. Ill have a look on the web. Many thanks
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