cdmAmsIj implements the Clean Development Mechanism (CDM) small-scale methodology AMS-I.J Solar water heating systems.
The package follows tidyverse design principles and exposes equation-level helpers, applicability checks, and meta-calculation wrappers to reproduce emission reduction estimates for solar hot water applications.
# install.packages("devtools")
devtools::install_github("independent-impact/GHG_methodologies/cdmAmsIj")library(cdmAmsIj)
applicable <- all(
check_applicability_swh_capacity(capacity_mwth = 12),
check_applicability_solar_resource(annual_irradiation_kwhm2 = 1850),
check_applicability_backup_fraction(backup_fraction = 0.15)
)
if (applicable) {
thermal <- tibble::tibble(site_id = 1, useful_heat_mwh = 420)
auxiliary <- tibble::tibble(site_id = 1, auxiliary_energy_mwh = 60)
baseline <- calculate_useful_thermal_output(thermal)
baseline_emissions <- calculate_baseline_emissions(baseline, baseline_emission_factor = 0.22)
project_emissions <- calculate_project_emissions_auxiliary(auxiliary, emission_factor = 0.18)
emission_reductions <- calculate_emission_reductions(baseline_emissions, project_emissions)
}For a full walk-through see the vignette in vignettes/cdmAmsIj-methodology.Rmd.
Projects must satisfy core AMS-I.J requirements before emission reductions can be claimed. Use the package helpers to document each criterion:
check_applicability_swh_capacity() – verifies the solar thermal capacity remains under the 45 MWth small-scale threshold for Type I activities.check_applicability_solar_resource() – confirms that the project site receives adequate solar irradiation to justify solar water heating.check_applicability_backup_fraction() – ensures auxiliary fossil or electric heating contributes only a limited share of useful thermal output.cdmAmsIj translates the numbered equations from AMS-I.J into composable R functions:
| Equation | Function | Description |
|---|---|---|
| (1) | calculate_useful_thermal_output() |
Sums useful solar thermal energy delivered during the monitoring period. |
| (2) | calculate_baseline_emissions() |
Applies the baseline emission factor representing displaced conventional water heating. |
| (3) | calculate_project_emissions_auxiliary() |
Estimates project emissions from auxiliary heating energy. |
| (4) | calculate_emission_reductions() |
Derives emission reductions by subtracting project emissions from baseline emissions. |
The meta-wrapper estimate_emission_reductions_ams_ij() chains these helpers together for tidyverse-friendly datasets.
aggregate_monitoring_periods() summarises measured data across reporting periods while preserving site-level identifiers and emission factors.simulate_ams_ij_dataset() generates example datasets with monitoring metadata, solar fractions, and emission outcomes to support tests, demos, and onboarding.