Claim: 90% of Verra Carbon Credits are worthless “Phantom Credits”

Because very few people actually deal with VERRA methods in detail, it is fair that I comment on the worthiness, or otherwise, of at least one of the VERRA emission reduction calculations, in this case the following document:

https://verra.org/wp-content/uploads/imported/methodologies/VMR0006-Methodology-for-Installation-of-High-Efficiency-Firewood-Cookstoves-v1.1.pdf

It is used in stove replacement projects, of which there are many. This seems like a fairly straightforward determination. It involves establishing how much wood a baseline stove uses, and then replacing it with an improved stove that uses less fuel to do the same about of cooking. The reduction is factored for the amount of a forest that is cut and does not grow back, because if it grows back 100% then the stove is using fully renewable fuel. The fraction of non-renewable biomass (fNRB) is the term used for this. In countries where there is a lot of forest cover and little chopping (and good regrowth) the % fNRB is low, perhaps 5% or 20%. In comes countries it is as high as 90%. It changes with time.

The VERRA methodology uses a lab test to establish what the fuel efficiency for the baseline and improved stoves are, then they sell the CO2 theoretically saved in the form of Emission Reduction certificates (ER’s) worth 1 ton each. The value of 1 ton is negotiable.

The test used to make the assessment is the Water Boiling Test, WBT-4.2.3. This is the method that claims to determine the savings, and thus the emissions reduction.

The WBT-4.2.3 is an interesting document. It was written by an ad-hoc technical committee of an organisation called ETHOS, Engineers in Technical and Humanitarian Opportunities of Service. ETHOS has no legal or statutory competence to create a test method, is not accountable to anyone for its many defects, and was thrown together because the defects of the previous WBT-3.1 were so blatant that it was impossible to ignore them any longer, for example that there were only 58 minutes in an hour.

The later version of the test (all versions 4.x) were analysed and soundly criticized in a number of published journal articles, particularly by universities in Italy, China and South Africa. It is not fit for service, containing multiple conceptual and mathematical errors which have no mechanism for resolution because is does not not have a Custodian. No one owns it.

The VERRA test method was thus not created by them. Why do they use it? It is taken directly from the Clean Development Mechanism (CDM) website. See footnote 12 in the document above.

“12 “CDM Methodologies Panel Clarification on water boiling test under AMS II.G (SSC_752)”

AMS II.G is the name of a CDM methods document. How that document was edited to include the WBT-4.2.3 is not clear. The method has never been published for peer review nor is there anyone to complain to about its obvious faults. Any criticism aimed at VERRA for using it can equally be aimed at CDM and Gold Standard for making misleading claims as to the relative efficiency of stoves and therefore the number of ER’s generated.

Specifically:

Page 16: “The high-power thermal efficiency is the average of the Cold Start and Hot Start phases”.

Let’s take one error to demonstrate the sloppiness of the methodology. The “thermal efficiency” (as defined, not as you might define it) is determined by heat gained by a pot/heat available during a “cold start”. This test is repeated with the stove already hot. The heat gained during the hot start is generally higher than during the cold start so the numerator is larger. The heat available during the hot start is usually quite a bit higher than during the cold start because the first run includes ignition, which takes time. The point I am making is that the numerators and denominators are expected to be different.

Efficiencies are fractions, always. The test produce two values, for example 30% and 40%, the first being strongly affected by the ignition and the thermal mass of the stove. These two numbers are averaged: (30+40)/2 = 35% no matter what the denominators are. It is averaging two fractions with different denominators, under conditions where the answers are expected to be different. This is not a legitimate procedure. The true average is the sum of the numerators divided by the sum of the denominators. This type of sloppiness occurs dozens of times in the test protocol, sometimes resulting in negative values of energy or mass. Needless to say, the WBT-4.2.3 does not predict fuel consumption nor thermal efficiency.

VERRA did not check the method; the CDM did not check it, yet they are trading money on the results. What is the effect of the sum or errors? First, it treats different kinds of stoves differently. Second, it overestimates the fuel savings, i.e. it overclaims the number of ER’s produced. It never under-estimates. Quelle surprise.

Claims related to avoided forest clearing are strongly dependent of the fNRB value because if it is cut somewhere in the country are grows back somewhere else, the net effect is zero: carbon neutral. Article 6 of the Paris Agreement is very specific about this being determined properly. Under CDM it was loosey-goosey for a long, long time. The new rules have been in effect for several years, why use the old rules?

A second aspect not mentioned in the article is that the rate of forest net biomass production rate is increasing because of CO2 fertilization. A project that starts with an fNRB of 20% and runs for 10 years will find the value drops to 5% during the life of the project because the 80% that regrows, plus the existing standing forest, pretty much out-grow the initial excessive cut-back. Globally, the net gain over 40 years in the biomass accumulation rate is astonishing. It is caused by the fact that most biomass is almost starving at 300 or 350 ppm CO2. Plants grow much better in the 1500-2000 ppm range – a regime under which they developed and lived for hundreds of millions of years.

Back to VERRA: They are using a defective method for calculating excessive ER’s for cooking stove projects because they copied methods, without review, from the Kyoto Protocol-based CDM library. It is quite possible for them to have done the same with forestry-related calculations.

It is all in the public domain. Read the methods, check the calculations, come back here and report. If they got it right, say so.