The efficiency of kiln drying firewood?

[gdh]

2 hours ago, Big J said:

I worked out the carbon cost for the supply chain up to the timber arriving into the firewood retailers yard, then made the assumption that that cost would be replicated again for processing, handling and delivery of the logs. 

 

I then worked out the co2 output from burning the required quantity of wood to run the kiln and added it to the process cost up to that point. Your system running at about 10% is the best case I've heard of, and would represent a 7-8 times increase in the co2 output, per cubic metre when compared to air dried.

I agree with the first part, I just don't see how putting it in a kiln is going to increase it that much. 

 

In all honesty, part of the reason we're effecient with drying is because we go over the higher tier RHI limit so, unlike smaller businesses, and the early kilnd that the salesmen were basically encouraging you to leave open, we have to be to stay competitive. Even now I think there's room for improvement because it's all relatively new ideas.

[SbTVF]

Why do pigs need so much heating?
 
Increases meat production/growth rate for lower feed input  or something?
 
 
Could pig sheds be better insulated  deigned with solar gain etc rather than burning wood to heat pigs which doesn't seem that enviro freindly?

An entirely valid point. Piglets grow best at around 30° from newborn down to 20° ish by 9 weeks old. They also need ventilation to keep the air fresh. So that's a trade off for a start.

The buildings are super insulated and after 9 weeks they generate enough heat from themselves to keep the heat up in the sheds with straw to assist.

[openspaceman]

3 hours ago, Puffingbilly413 said:

I wouldn't say heating your house is a luxury. 

Nor would I

3 hours ago, Puffingbilly413 said:

Wood still remains the cheapest option for many, especially in rural communities.  I heat my house mostly on wood (albeit it's all arb 'waste'). 

I do too and cut and split them, none of it sees the inside of a kiln

3 hours ago, Puffingbilly413 said:

There are some good case studies on using log boilers - they certainly seem to be a lot cheaper than the air source heat pump we have (a bad choice, wish I hadn't gone down this route but there you go).

Tell me more, I know of a couple of heat pump installations that were abandoned but then I know of a few chip and pellet boiler installations which were failures.

 

I know when I sold logs that none of my customers used them as their main heat and at £100+ for a bulk cubic metre I cannot see how they compete against other commonly available fuels.

 

[Woodworks]

4 hours ago, Puffingbilly413 said:

  There are some good case studies on using log boilers - they certainly seem to be a lot cheaper than the air source heat pump we have (a bad choice, wish I hadn't gone down this route but there you go).

 

 

It will depend what you have to pay for the logs and the efficiency of the instal which can vary drastically. We have a ground source heat pump (GSHP) and it's cheaper to run that  for the heating and sell the logs. Not that we do this as we love a fire and there are always some dodgy logs we would rather not sell so we use them in combination with the GSHP

[Puffingbilly413]

1 hour ago, openspaceman said:

Tell me more, I know of a couple of heat pump installations that were abandoned but then I know of a few chip and pellet boiler installations which were failures.

 

I know when I sold logs that none of my customers used them as their main heat and at £100+ for a bulk cubic metre I cannot see how they compete against other commonly available fuels.

 

It was the Eco Angus case studies I looked at - I'd have to check back but I think for a large detached stone house they were using 12 cube a year, but that was to maintain the house at a constant 20 degrees (the family in the study had a newborn at the time I think).  They had a small wood, joinery business offcuts and also bought some fresh cut logs in to season.

 

Like others have said, a lot of this comes down to room, but if you have the space to dry 12 cube from green, then it clearly would be cheaper.  Even at £100 a bag that still less than what I used to pay for gas and electric heating the house the conventional way.  Add in the RHI element and it's paid off soon and would see you break even at the very worst.  If you have your own wood source then even better.

My heat pump was £14k (inc installation, new rads etc) but packages for gasifiers start around 5k).  I only wish I'd known about them before we went the route we did.

[Puffingbilly413]

4 hours ago, Woodworks said:

I dont think thats the case for all. Sure if you have mains gas its a luxury no question but we deliver to many who are either on oil or some who have no other form of heating other than wood. In this relatively rural area I would estimate only 25% have mains gas

I still wouldn't say it's a luxury using logs if mains gas is available.  At least not if you're serious about moving towards renewable energy, which gas is never going to be.  In fact, the RHI scheme is supposed to encourage exactly such a move.  Gas central heating is def on its way out I think within the next decade or so.

[doobin]

I can't see gas going any time soon. People talk about their log customers, who only have a log burner, like it's the norm. It's not. For every cosy stone cottage with a wood burner, there are a hundred flats heated upon gas in the towns and cities.

 

By luxury, I mean that gas is cheaper than logs bought in. Someone on here once worked out the cost per kwH of logs vs gas or oil. It was a huge difference, and gas is pretty cheap right now.

[Woodworks]

1 hour ago, doobin said:

Someone on here once worked out the cost per kwH of logs vs gas or oil. It was a huge difference, and gas is pretty cheap right now.

There is this https://nottenergy.com/resources/energy-cost-comparison/

[Rob_the_Sparky]

15 hours ago, doobin said:

I can't see gas going any time soon. People talk about their log customers, who only have a log burner, like it's the norm. It's not. For every cosy stone cottage with a wood burner, there are a hundred flats heated upon gas in the towns and cities.

 

By luxury, I mean that gas is cheaper than logs bought in. Someone on here once worked out the cost per kwH of logs vs gas or oil. It was a huge difference, and gas is pretty cheap right now.

Not only that, gas, electric and water do not need carrying into the house and the stoves don't need loading manually.