*WARNING*
This thread contains boring wood/logs/biomass/heating calcs/energy stuff. Turn back now if this is a problem for you…

Last Saturday I hired a mate and his tractor and trailer to help me get all the wood from this winter’s harvest at the coppice back to the house for seasoning.

Over the winter I had managed to fell about 0.4 of an acre (I have 3.5 acres at the coppice ready for clearing). I had wanted to do half an acre a year but ran out of time before the season passed.

Back at base

This week I have mostly been playing the biggest game of single player pick-up-stix in the county

Maths bit (particularly for Sharkbait and DD)
BTW, deadlydarcy, http://bit.ly/17tuT5n

this link covers the thing about all wood having pretty much the same net calorific value for a given moisture content.

The stack is 1.5m high, 9.6m long, and 1.5m deep. It’s tightly stacked so assuming 10% loss of cross section to air space gives a total volume of around 19m3.

Poplar has a dry (c.10% moisture) density of c.450Kg/m3, so given water is 1,000Kg/m3 and the wood currently has a moisture content of around 30-35%, then the wood has a density of c.600Kg/m3 at the moment.

So I hefted 11 tons of wood into the trailer and then stacked it this week. No wonder I hurt.

When the poplar is air dry (12% moisture) it will have a net calorific value of around 4,000 kWh/ton, or 4kWh/Kg.

So that pile will produce something like 35,000 kWh of energy.

(just for the giggles: that’s worth £5,500 in electricity, or £1,600 in gas or £2,500 in oil 🙂 )

My deemed Central heating energy usage is about 15,000 kWh a year and for the domestic hot water requirement over the months when the solar thermal tubes aren’t providing it I need another 3,600 kWh of energy.

So that one year of harvesting should cover just under two years of consumption. I think I’ll take next year off then….maybe….

The hire of my mate and his kit cost £200, but I have also processed around 300 stakes for another mate who lays hedges and they’re worth about £100. In future years my mate and I may come to a deal where I shall trade some timber for free delivery of the rest as he has plans to use a kindling processor for some of the poplar.

With the best intentions, I hate you and your enviable life….

DrP

😉

(This is exactly the sort of thing I’d love to be doing – self sufficiency etc etc!)

Aye, come the zombiepocalypse I can still heat my beans 🙂

take a few and stick them somewhere mixed sun/shade and keep them wet to make them rot – insect happiness leading to bird happiness

I already have some “habitat” stashes around the field like that. Usually using any lumps that I cant split with the maul. Its been great working down on the stack this week as it’s down where Ive put most of my bird boxes so the robins, tits and wrens have been rattling around me all day and I can hear the racket from their chicks on each delivery of nosh.

I do need to find some 2m wide tarpaulin on a roll to cover the stack for the winter though.

My only concern is the robin has nested in the bank of long grass, on the ground and I saw a neighbours cat around recently….where’s that other thread….?

come the zombie apocalypse I’m coming to yours Mark 😆

You need another wood store, you’ll never get all of that in there [Shouts]McMooter![/Shouts]

I echo DrP’s comments. 🙂

doh, wrong link in OP

http://bit.ly/15GLEWY

Keith – bring beans and ammo and you’d be more than welcome.

Nice one 🙂
Are you going to cover that stack or leave it open for a while? Nice calcs although I bet the air gap actually amounts to a bit more than 10%.
You’ll need to get it used as I’ve read that poplar can rot quite quickly if not kept very dry.
Good to have your supply sorted for the medium-long term too.

Was the coppice there when you bought it or have you planted it all?

I’ve got an unused paddock that’s about 1.2 acres and have been thinking about how to make it pay and xmas trees is top of the list right now. If I planted up at the recommended spacing I could fit 5000 trees in which would give a return of approx £100k in 6 years. 😯

Impressive, shouldnt it have been nerdstatstrackworld? You splitting by hand or mechanical log spliter? I’m after a tractor mounted one, mainly to save my joints when sorting the folks winter fuel supplies out.

I have plans to get a long bit of tarp over the top.

Ive been conservative in my other calcs. Anyway, a circle in a square is already 78% efficient before you allow for corner filling…. 🙂

Poplar will rot if left to get damp, i.e. on the ground (the stack is laid on salvaged railway sleepers from the refurb of Foregate Street bridge in Worcester), or in shaded no-draught. If kept rain free and draughty it will keep ok. Anyway, shall only be storing for 2yrs.

The poplar coppice is an abandoned poplar plantation 6-7years after being clear felled.

before

After

Now

The guy who owned it for those 6 years did nothing to it. So its a lot of work to get it into shape.

I planted 500 whips of fast massing willow varieties in the paddock at home which are now in their second year, having cut them back to a stool height last winter. They will be grown on 3yr rotation.

This was last year. You can see how they look now in one of the pics in the OP.

Insulating those stone R = 0.000006 walls has got to be easier than doing that every year. 😉

Edit: though the tax advantages won’t be as attractive as woodland.

Ed, I’m comfortable with my u-values thank you 🙂

Oldagepredator I split all my wood by hand. Small cord poplar will split quite easily but I’m going to treat myself at the Arb show in a few weeks to a new axe, larger than a kindling axe but still Ok for one-handed use as the maul is a bit overkill for that stuff.

Sharkbait are you going to Arb show?

I’m going to treat myself at the Arb show in a few weeks

Fiskars X25?

Your central heating and hot water requirements are 18600 Kwh per year? Wow

My entire household usage ( with no gas in our village) was 8400 last year.

Everything I deal with has either come down the river or is wind blown, rarely fell anything. Usually big and tough – hence looking for a robust spliter. Although I’m thinking about bringing a couple of the smaller woods back into production – alder copice tips anyone? Firewood is usually beech, ash or sycamore.

Take a lump of wood to try when you buy the axe. The advantage of the maul is its broad blade doesn’t get stuck. When I used a narrow-bladed cutting axe the thing was forever getting stuck. I know it’s manly/showy/trendy turning the thing over and finishing the split with the weight of the wood but it’s much easier to swing the maul a second time.

There’s something suspicious about your domestic hot water use. Our total electricity consumption (1645 kWh for hot water, lighting, cooking not done on the wood burner, TV, my son’s Marshals, computers, fridge, power tools and anything else we plug in) is less than half what you use just for hot water despite five times as many thermal solar panels as us. You must have a least five women regularly washing themselves hidden away in those outbuildings.

Stoner, how are you finding the regeneration of the coppice/establishment of the withies is going? is there a significant deer population there and are they hammering the willow more than the other areas?

The willow whips are doing really well – we’re on a clay bank, quite wet at times and no deer. Whips protected from rabbits with plastic boots. I have on average between 8 and 12 cords on each stool now (having cut back first growth from the whip at the end of the first year) and these are a 50:50 mix of Q83 hybrids and Viminalis Salix.

Ed – I understand the maul, hence why I own one, but for the poplar with a finer grain and smaller diameter I want something that doesn’t ping the wood into the next county each cleave and can be wielded with one hand for speed. Young poplar really does split just by looking at it hard enough. Old poplar is the spawn of satan though.

My DER (DHW + CH) is calculated from the SAP for the new build. It comes out at <100 kWh/sqm/pa which is around 15% better than building reg targets in 2009 when this was specified.

Im using a rule of thumb for DHW consumption of 20kWh a day. Toppy I know, but Im sure Im not using that much. I dont have a method of accurately recording energy provided by the furnace or the solar panels. Next toy will be a calorimeter of some sort to do so.

geoffj – that’s the kind of thing, or maybe the X17. Workware have a stand there with a pretty good range to fondle I hope
http://www.workware.co.uk/categories.php?category=Products/By-Product/Axes

I’ve got a heap of platane (plane tree?) waiting to be chopped up. Not something I’m looking forward to. I think I’ll give my wedges a grind as the maul just bounced off the last lot.

I’m teasing about your energy consumption. I doubt my house is much better it’s just smaller and a lot further south, and everyone knows about our soap consumption.

platane (plane tree?)

I guess its the same as the London Plane tree – I assume you mean the kind of tree that french avenues are lined with?

I got given a pile of v old poplar from a trunk my dad had felled in his garden. **** impenetrable! It now forms a surround for my bonfire pit. Waste of time trying to process it into logs.

ninfan – a better pic of how the willow is coming on:

Awesome work Stoner!

Oooh lovely.

Could you get some wild flower borders around the edges?

Edukator, there is no chance you get your platane chopped without a power tool.

The last time I chain sawed the platane to 30cm, failed, chain sawed it to 15cm, had trouble, chain sawed slots and used wedges to make the first split. Mais comme dit mon voisin élagueur, le bois a l’avantage de chauffer trois fois: il faut le couper, il faut le débiter et à la fin, on peut le brûler.

et maintenant vous etes trop chaud, non?

Bunnyhop – the problem with wild borders is bringing them under control after a couple of seasons. We’ve tried it a number of times and have worked out how to do it in small areas, but across the meadow it becomes a real challenge. We do front a 3,000 acre common so habitat is not a problem. I aim to create slightly different habitats for woodland birds rather than grasslands, as they are catered for in abundance around here.

Cheers mcmoonter.

Good work that. Will this mean you won’t be using many pellets?

22°C sans chauffage ni clim.

the plan is to use c. 1/2 ton a year (£125) and that’s just for overnight in the coldest winter nights or when Im away and Mrs Stoner doesnt fancy firing the furnace, although she’s very well trained now…

Sounds good – a bit like my approach to the oil boiler.
Unfortunately mrs j isn’t as well trained in maintaining the stove – although I have now installed a ‘stat which turns the rad pump on once it threatens to boil the TS so she can’t blow it up!

lol – you mean to cover you from when you fall asleep!

I left Madame at home for a week when it was ten below zero. When I got back two months’ worth of kindling had gone, there were no old newspapers left and a small wood pile had disappeared. My son was sitting in a T-shirt.

lol – you mean to cover you from when you fall asleep!

8)