[Stoves] Shields E450c as a way to test char-making stoves (attn: GACC testers)

[Ronal W. Larson]

Crispin  cc list

    1.  Can you clarify your view on two points, which I take to be your viewpoints:

      a.   There is no way to accurately test a char-making stove  (I say because you have not answered my requests for a test you would favor) .

      b.  The present 4.2.2 WBT (Water Boiling Test), used by Jim Jetter and approved by the GACC,  which reports both amount and energy of produced char, is fundamentally in error.  (This is what I gather from the following).

Ron


On Oct 22, 2013, at 12:20 PM, Crispin Pemberton-Pigott <crispinpigott at gmail.com> wrote:

> Dear Paul
>  
> I can’t keep track of who you are sending that to. I will continue here.
>  
> >NOTE:   There is char remaining at the end of the batch.  Crispin wants 
> the unburned char to be counted as fuel used.   Others want the char to 
> be valued as fuel for other stoves or as biochar or as atmospheric CO2 
> removed.   This debate is AN important question if discussing the amount 
> of original FUEL that is used.   But it is not THE important question 
> concerning the stove efficiency of ENERGY released (with some amount 
> captured in the pot so that ENERGY efficiency can be calculated).
>  
> I feel it necessary to add the words missing from the above:
>  
> Crispin wants the unburned char to be counted as fuel used if that char cannot be considered fuel for the stove being tested at the time.
>  
> This is not a fine point, It is basic to the rating and prediction of fuel consumption.
>  
> In many cases (I am chasing a new one) the remaining char is fuel for another stove. Fine. That stove will be rated according to how it uses that char, and what is unburnable leftovers will be considered ‘consumed’ by that char burning stove. The point is no one gets to double dip on the energy, altering (lowering) the claimed fuel consumption by pointing out that the ‘energy used’ is a lower number.  Used energy is always a lower number than available, but that should not distract us.
>  
> >We really do need to differentiate between the FUEL and the ENERGY, 
> especially when a substantial amount of energy is not extracted from the 
> fuel, as is the case of the remaining charcoal.
>  
> Exactly! Thank you.
>  
> >This was not a problem when the only stoves available essentially took 
> all of the energy out of the fuel.   But that is no longer the case and 
> we need better definitions of "efficiencies".
>  
> Well, in the 1980’s it was recognised as a problem and the Eindhoven Group and VITA both started discarding all remaining fuel as lost. They never, as far as I know, even tried using the leftovers that were burnable as part of the fuel in the next cycle, even when it was obvious that was happening on the ground. From what I can find, testes were always started with 100% new raw fuel.
>  
> >With fossil fuels, we calculate that we get all of the energy released 
> from the fuel.   BUT those are PROCESSED fuels like LPG and kerosene or 
> even "fuel oil".  If you consider all of the original fuel (such as 
> crude oil), then there is a great amount of ENERGY in the "other stuff" 
> that is not available via the stove.    Should that be called "non-fuel" 
> and be counted against the processed fuel's efficiency?   No, not 
> really.    Other derivatives of the crude oil have their own uses and 
> values, of which some are not even for energy (such as asphalt).
>  
> It is reasonable to make such a system analysis of the raw material. The point we face as testers is that we are asked what happens with this stove using that fuel. Period. 
>  
> >Charcoal made from wood fuel is no longer wood.  And therefore the FUEL 
> efficiency denotes the 100% disappearance of the wood.   But in terms 
> for ENERGY efficiency, 100% of energy in wood = energy in charcoal  +   
> E450c.
>  
> That is one way to look at it.
>  
> >Crispin argues that Fuel efficiency needs to be reported.   This can be 
> important in areas of severe deforestation.   But that thinking is 
> deficient in three regards:
>  
> Let’s look:
>  
> >1.  Tradition has used the term FUEL as if the amount of fuel could / 
> should / must be equated to the amount of ENERGY that is released.   But 
> that equivalence is no longer the case when a significant "left-over" 
> (by-product or co-product) is created, as in the case of the charcoal.
>  
> The view is correct for certain fuel types, but it is not for biomass because of the way it burns. 
>  
> >2.  Tradition has focused on wood as if it were the only biomass fuel 
> that truly matters in cookstoves.    That is no longer the case now that 
> pyrolytic microgasifiers that use many other forms of biomass are 
> acknowledged to be serious candidates as clean cookstoves.   [And that 
> acknowledgement is certainly less than 8 years old, and maybe not even 
> acknowledged by some still today. Sad but true.]
>  
> Well….charcoal has long been recognised as a biomass fuel. How it was produced varied. Gasifiers have been around for a long time, making charcoal. 
>  
> >3.  Therefore, if FUEL conservation (or efficient usage) is the battle 
> cry of the testers for fuel efficiency, then the use of NON-wood fuels 
> means that the micro-gasifier stoves need to be credited with using NO 
> wood from the forests and are therefore far superior than the 
> wood-burning stoves in regard to the saving of forests (and watersheds 
> and animal habitats and biodiversity, etc.).
>  
> That is unfortunately not the case – though some are still trying to make it (because it has certain merits). The availability of non-woody biomass is not a ‘given’ in many places. There are huge amounts of wasted biomass (burned to get rid of it) but that does not mean a generalisation is possible. Looking at the UNFCCC rules for what constitutes ‘sustainable biomass’ can lead to the conclusion that fuel efficiency (whatever the form of the biomass) is important. That is a general case, however there many places with an excess of something and others where everything is used. 
>  
> A policy manager might conclude that in their target region there is plenty of non-woody biomass and to save the forests from chopping, they will use the alternative. This does not have to be put into pyrolysers, it needs to be burned ‘somehow’ and a pyrolyser is one way to do it. It might be made into pellets or briquettes or powder. We should be technology neutral when making rules.
>  
> >Summary statement and plea:   Let's get off of the "wood standard" and 
> get on the energy standard.
>  
> We can do that, if we do not at the same time create a rating method for stove performance that lies about the fuel consumption. 
>  
> The issue for me has been that test methods have been mis-reporting actual performance and misleading programme managers who make decisions about what technology they want to support with their $$. 
>  
> 1.       Stoves with equal performance shall receive equal ratings.
> 2.       Stoves with unequal performance shall not receive equal ratings. 
>  
> If the mathematics of the test method provides a rating that contradicts either of those rules, it needs to be investigated and corrected. If a metric is the actual problem, change the metric (calculate something else that is representative of performance). 
>  
> When it comes to mass of fuel consumed, the energy in it and so on, the lab is agnostic. There are no holy stoves and there are no holy fuels. The stove does what it does, emits what it emits, and consumes what it consumes. We just report it. Don’t shoot the messenger.
>  
> Thanks
> Crispin
>  
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