Winter log usage

[openspaceman]

5 minutes ago, Squaredy said:

The figures are simple:

Too simple as your units are wrong but I agree with the gist of what you meant to say

 

1bulk cubic metre of wood seasoned to 20% weighing about 250kg?? contains 1000kWh and costs £100

 

It also burns less efficiently than the others so more heat is lost

[Squaredy]

46 minutes ago, openspaceman said:

Too simple as your units are wrong but I agree with the gist of what you meant to say

 

1bulk cubic metre of wood seasoned to 20% weighing about 250kg?? contains 1000kWh and costs £100

 

It also burns less efficiently than the others so more heat is lost

I worked out a bulk cubic metre of loose logs properly dry as 300kg approx.  I don’t think this is far out.

[neiln]

I agree wood if bought would be more costly than mains gas but my estimate, based on my reduced gas bill and adding a bit more as the house is warmer with wood, each cube of mixed wood saves me ~£60.  So £60 gas = about £100 of logs. Ish. 

[gdh]

300kg sounds about right for a cube of dry wood. If you were relying on wood you probably would buy bigger loads though. I think with our prices it would be 8-9p a kw with a 4cube load.

 

Woodchip for comparison is 4-6p a KW on a contract.

 

 

Edited February 4, 2020 by gdh

[Woodworks]

1 hour ago, openspaceman said:

Too simple as your units are wrong but I agree with the gist of what you meant to say

 

1bulk cubic metre of wood seasoned to 20% weighing about 250kg?? contains 1000kWh and costs £100

 

It also burns less efficiently than the others so more heat is lost

I have a cube at a fair bit more 

 

[openspaceman]

9 minutes ago, Woodworks said:

I have a cube at a fair bit more 

 

Yes beech is about the heaviest but I was trying to work backwards from the 10p/kWh figure. 350kg to the bulk cubic metre at 20% drops the price to just over 7p per kWh.

 

@Squaredy I was pointing out the unit of energy is kWh the W is capitalised as it is named after Watt. Whereas we don't capitalise wattage ? and the h is for using the power for an hour.

 

 

[Steven P]

Sounds about right for cost per heat output, If you have only electicity then solid fuel is good. If you can get them for free and ignoring the time you put in yourself then logs are good.

 

f I had to pay for solid fuel I would buy coal and never wood - cheaper for the heat output, takes up less space, fire stays in longer, no arguments about smoke - it is all smokelss that I get (well, mostly...).

 

For many of us adding anything other than a stove is going to be big money (OK I am a special case, gas main to the house was going to be 10's of thousands apparently), central heating boiler at £1k installed? radiators and pipes - another £1k? Gas tank - the same again? Gas conection if the pipe is utside the door £1k? which is another factor to take into account. that is quite a lot of kwh worth of wood to make it a saving (hoever, it makes the house worth more when you cme to sell it). It's a tricky thing to work out what actually is the best value if you look outside the raw fuel costs.

 

Things are gong to get easier - and mre exensive - when the government turn off the domestic gas supplies, electric only

 

The nowegian wood book is worth a read here.

[Squaredy]

26 minutes ago, Woodworks said:

I have a cube at a fair bit more 

 

I guess I was working on kilned logs so average more like 15%.  That would make our figures about the same.

[neiln]

Agree Norwegian wood is a great book.

 

To heat with wood through choice you have to enjoy it, the fire I mean.  To cut, split and stack the wood yourself you must also enjoy that bit.  Currently I love it, when I get bored ... I'll do a lot less and happily run the gas Ch.

[arboriculturist]

My figures compare similarly for 100% Hardwood:

 

20% MC 300 Kg

 

25% MC 330 Kg

 

These figures vary with species of course but represent a fair average for 10" long split logs.

 

We get through 15 - 20 m3 of offcuts in a draughty farmhouse with no insulation whatsoever at this stage ?