Rape straw biomass boiler

[Huno]

You are assuming i don’t know much about any of them though...

From memory a dragon has about 1/3rd of the tubes a F200 has.

Having seen fuel uses for all 3 vs outputs I maintain my stance.

Just an opinion of course. But I’ve been involved in biomass since 2012

 

[Huno]

That makes sense! If you include steam rooms in submarines i have been playing since 1999!! God im old! Cheers

 

[scotston]

That makes sense! If you include steam rooms in submarines i have been playing since 1999!! God im old! Cheers

I've got a spanner CHP. Fitted it at the top of the subsidies. Everyone needs to look at their own figures but it generates 300mW electrical per annum which keeps our leccy bill less than 10k. Frightening to know what it would be without it. We had an old dragon installed 1996. D50 that replaced it in 2012 was to keep doing what we were already doing but get rhi for fun. Now with daft energy prices this thread makes everyone think about what they do to make their business more efficient. Without subsidy.

 

[Still Farming]

I've got a spanner CHP. Fitted it at the top of the subsidies. Everyone needs to look at their own figures but it generates 300mW electrical per annum which keeps our leccy bill less than 10k. Frightening to know what it would be without it. We had an old dragon installed 1996. D50 that replaced it in 2012 was to keep doing what we were already doing but get rhi for fun. Now with daft energy prices this thread makes everyone think about what they do to make their business more efficient. Without subsidy.

Did you replace a dragon with a dragon?

 

[scotston]

Yep. Old one was tired and needing updated. The d50 gti is totally redesigned and works really well. But I'm sure the other makes are just as good...

 

[Doing it for the kids]

This is where my basis initially came from - which if the three below strike you as most efficient?!

 

[scotston]

still odd - a picture of a brand new one and a picture of a machine that needs cleaned? A fair comparison?? Don't know how to open a HEIC file?

 

[Doing it for the kids]

for some reason i phones now use HEIC files - PIA. try now.

my point is two have 5 secondary tubes, the 3rd has about 40. that's a huge amount more surface area. This is backed up by what i have seen from all three's efficiency in the real world. these are all same output ratings.

They all work as shown from other users, but when you compare them it becomes more apparent why they all perform like they do.

 

[scotston]

I think mine has around 14 at 70mm diameter. I would not want to have to clean 40 so I'm going to agree with you that lots of pipes increases surface area (of the smoke part) but then they all get furred up and stop working. They all need cleaned otherwise they all lose efficiency therefore I'm happy with my setup. As an aside I fitted a centre-less auger to increase turbulence in each pipe and really helped to keep them clean. Also it should be noted that there is no measure of efficiency for any of the machines but happy to accept your experience of them all as I do not have that.

 

[Huno]

Did you replace a dragon with a dragon?

Yes, Dragon D50 gti is a good bit of kit... simple to set control systems and the best for straw or waste wood burning on the market

 

[scotston]

Don't say that. We've just agreed that they are all good machines, with differing characteristics. But broadly the same. It could be completely academic if there are emissions rules..

 

[Huno]

This is where my basis initially came from - which if the three below strike you as most efficient?!

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If the stratford on avon pic is a dragon then they now have alot more heat transfer pipes in the top these days so more efficient and double bypass but it is all about lagging and accumulator tank design for real thermal efficiency

 

[Huno]

Yes they are all good machines.. for sure

 

[KennyO]

@scotston what was your original dragon?
I have a single pass type that takes a round bale. Have toyed with swapping it for a newer one to make it more efficient. You obviously have experience of both.

Do the newer types create any less smoke?

Is there a serious chance that they won't be allowed to burn straw due to emissions?

 

[Bokey]

Because even one built to RHI specs can occasional behave like a Bomb is about to go off when they overheat! Good luck with the insurance claim.. Boilers are scary and need respect..

Pressure relief valve or even safer is an open topped expansion tank but then you need to keep check of water level through loss with evaporation

 

[Still Farming]

Yes, Dragon D50 gti is a good bit of kit... simple to set control systems and the best for straw or waste wood burning on the market

2 round bales with pipes in type is it.

 

[Doing it for the kids]

If you put an insulated lid on and have a brass float valve it’s not so bad, you can hear when they are topping up, gets quite tuneful if she gets hot to!

Open systems don’t work though if the site is on a gradient but as others have said, serious volumes of very hot water need respect

 

[Bloders]

i removed the accumulator from our Glen Farrow and replaced it with a vented tank. Works much better.

 

[scotston]

@scotston what was your original dragon?
I have a single pass type that takes a round bale. Have toyed with swapping it for a newer one to make it more efficient. You obviously have experience of both.

Do the newer types create any less smoke?

Is there a serious chance that they won't be allowed to burn straw due to emissions?

Definitely less smoke as the air into the chamber is different from the old one. It has the same under box section but also 6 over pipes that drive air in the top of the chamber. This 'gasifies' the fuel once it gets going. Also the old one had two little fans at the front, upper and lower. The new one has one giant rear fan that you can split the proportion of air to the upper or lower. No blowback with a 300mm flue. I think emissions and rhi were linked, but surely now, without rhi, you could replace it and no one would care?

 

[scotston]

Original was a double pass 2 bales. You had the choice to bung the outlet to encourage the smoke to go double. These were the rubbish ones that weren't very good as previously mentioned. New one wiped the floor with it but I can see that some folks would not be best pleased with the dragon Corp.