'Best practices in application of sampling under
PoA framework: DOEs perspective'
Workshop on Programme of Activities (PoA) under the CDM:
Challenges and Road Ahead
07th - 8th May 2011, Bonn
UNFCCC Secretariat
Contents
 Data sampling – Approach (general)
 Data sampling & Verification - Best practice example
 CDM Methodologies (general)
 Sampling plan- issues to be addressed
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Data sampling – Approach

Sampling determines the reliability of the parameter value estimate expressed in terms of probability of
a parameter falling within a specified interval around a parameter’s true value

Tools/guidance (sampling guidance EB50, annex 30)
• Methodological guidance, otherwise 90/10 confidence/precision as the criteria for reliability of
sampling

Over estimation of the mean value should be avoided, unbiased and reliable results ensured

Simple random sample
• most commonly used approach
• each observation chosen randomly and entirely by chance
• presents unbiased estimate of true population,
•
suitable for relatively homogeneous population

Systematic sampling, Stratified random sample, Cluster sampling, Multi stage sampling

Explanation of why the sample size is reliable and accurately reflects the population

Statistically sound sampling
• 95/5 precision (95% confidence interval and 5% margin of error)
• 90/10 precision (90% confidence interval and 10% margin of error)
• 90/30 precision (for eg. leakage)

Unique IDs- double counting avoided, verification status can be determined at all times
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Real Projects- Verification Approach


Gold Standard methodology for Improved
Cook-stoves and Kitchen Regimes V.01 (
CDM Meth AMS IIG)
6627 stoves were installed during the
first year of the crediting period
Province
Municipalities
Approximate population
Santa Barbara
28
342,054
Copan
23
288,766
Lempira
28
288,766
Intibucá
17
179,862
 Scalable to 1 Million plus installations
Verification challenges (MP1)

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Access, Travel time
Limited annual ERs (~15000) – Costs
On site - Man days
Population characteristics, record and
installation database of every stove constructed
incl. family name, ID number, location, and date
of construction for all the households that
receive a stove
1,788 monitoring surveys that include leakage,
sustainability and qualitative fuel use data
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Verification approach
 Statistical justification, Reasonable Assurance
 Key monitored parameters


Number of stoves installed (~350 samples)
Continued use of stoves over time – Drop off rate (alteration from original
configuration)
– PDD states that this shall be done through a survey of first 50 beneficiaries who
had stoves installed within the first 12 months of the start crediting period
– MR1 stated that a total of 1787 households were surveyed in 2009 and 2010; of
these only 28 stoves were found to be out of use - drop off rate of 1.57%
– Does the sample selected represent the entire population (spatial and temporal) first 50 beneficiaries only?
– Verification of 30 households in one locality (1/2 man day) –random sample
indicated 3 drop off (indicating 10% drop off)
– 3 more localities selected, 30 h/h each
– Sample size increased to 120 households across three randomly selected
locations (samples)
– Drop off rate found constant (7.5%) across the selected samples
(90% confidence level, 5-10% error margin)
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Verification Approach
 Statistical Justification, Reasonable Assurance
Emission reduction achieved per stove per year
» Registered PDD - 2.23 mtCO2e/year per stove (qualification attached- paired sample test)
» MR1 - 2.73 mtCO2e/year per stove
 Paired sample Kitchen Test for annual emission savings per stove (2010 Paired
Fuelwood Consumption Study)
 Measure daily fuel consumption over a 4-day period in 50 households stoves, random
selection, monitored before adoption of the La Justa 2x3 vis-a vis traditional stove
(fogon)

Actual sample size taken by PP was larger (reaching n=55); and wood was weighed
over a 5-day period (not just a 4-day period as required), resulting in four 24-hour
periods of fuelwood consumption data rather than 3
 Confidence level- 90%, SD of population- 0.168
 Reliability directly proportional to numerical sample size
 Large sample size and paired design, sampling approach, assumptions & justification
of approach transparently reported
 Eliminated systematic underestimation
 Original datasets available, Yale university staff (Third Party) - on site
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The sampling plan submitted by project proponents is reviewed
using to assess a range of issues and questions, such as:

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
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Does the sampling plan present a reasonable approach for obtaining unbiased,
reliable estimates of the variables?
Is the data collection/measurement method likely to provide reliable data given
the nature of the parameters of interest and project, or is it subject to
measurement errors?
Is the population clearly defined and how well does the proposed approach to
developing the sampling frame represent that population? Does the frame
contain the information necessary to implement the sampling approach?
Is the sampling approach suitable, given the nature of the parameters, the data
collection method, and the information in the sampling frame?
Is the proposed sample size adequate to achieve the minimum
confidence/precision requirements? Is the ex ante estimate of the population
variance needed for the calculation of the sample size adequately justified?
Are the procedures for the data measurements well defined and do they
adequately provide for minimizing non-sampling errors? Is the quality control
and assurance strategy adequate? Are there mechanisms for avoiding bias in
the answer, including possible fraud?
Are the persons conducting the sampling activities qualified?
(Ref. EB50, annexure 30)
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Methodologies (CDM Portfolio)
 AMS ID : Hydro Projects, AMS IIIF (Municipal Waste), AMS IIG
(Efficient cook stoves), AMS IC (eg. Solar thermal), AMS II J (CFL
Lighting)
 Sampling approach justified, consistent monitoring plan applied across
all CPAs, technical specifications are similar, operational
criteria/equipment provider same
 Statistically representative
 Issues: temporal and spatial aspects
 AMS ID & AMS IF (Hydro, Wind, Biomass, Photovoltaic) & other
methodological combinations
 More complex
 Sampling approach for each category
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
Employs 59,000 people and operate a network of more than 1,000 offices and
laboratories around the world

Largest verifier of CERs issued under CDM
Questions?
Siddharth.Yadav@sgs.com
Contact +44 7712785772
Thank You
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