Access Carbon Market Data from Emissions Trading Systems and Voluntary Registries • carbondata

Access carbon market data in R. Emissions trading system prices and verified emissions, voluntary carbon credit registrations and retirements, and global carbon pricing data from compliance and voluntary markets worldwide.

Carbon markets now price 12 billion tonnes a year. The data is a mess.

Carbon pricing has gone from a niche instrument to a systemic part of global climate policy. Around 12 billion tonnes of CO2-equivalent are now covered by some form of carbon price, about a quarter of global emissions. On the data this package returns, EU ETS primary auctions raised EUR 43.2bn across 213 auctions in 2025 at a mean settlement price of EUR 73.45, the EU ETS covered 1.19 billion tonnes of verified emissions in 2024, and the voluntary registries have issued 2.65 billion credits since 1996. Article 6 of the Paris Agreement is bringing a further wave of international carbon trading online.

The catch is that the data is scattered across dozens of jurisdictions, agencies, and registries, each with its own format, access pattern, and quirks:

EU ETS publishes verified emissions and allocations via the DG CLIMA Union Registry as XLSX files with year-specific UUIDs, and auction prices via EEX as per-year XLSX reports
UK Emissions Trading Registry publishes compliance and allocation reports as XLSX, with date-stamped filenames that change on every republication
RGGI publishes per-state allowance distributions as XLSX on a stable year-parameterised URL, but clearing prices only as per-auction PDFs
California Air Resources Board serves auction prices and caps as stable CSVs from ww2.arb.ca.gov
ICAP Allowance Price Explorer exposes cross-ETS prices via an undocumented but stable JSON endpoint
World Bank Carbon Pricing Dashboard publishes an XLSX twice a year, with a filename that encodes the release date
RFF World Carbon Pricing Database published per-country CSVs on GitHub until May 2026, and now serves current data through its own API
Berkeley VROD aggregates five voluntary registries into a bimonthly XLSX release
CarbonPlan OffsetsDB publishes parquet snapshots of voluntary credits to a public S3 bucket (the REST API was deprecated in 2026, and daily publishing stopped mid-2026)

carbondata wraps the stable, free, API-accessible sources through a consistent R interface, handling URL resolution, caching, and schema normalisation so you can get on with the analysis.

Installation

install.packages("carbondata")

# Or install the development version from GitHub
# install.packages("devtools")
devtools::install_github("charlescoverdale/carbondata")

Data sources covered

Source	Coverage
EU Emissions Trading System (via EEA)	Verified emissions, free allocations, surrendered units, installation registry, EUA prices (2005-present)
UK Emissions Trading Scheme	UKA auction prices, verified emissions, allocations (2021-present)
Regional Greenhouse Gas Initiative	Auction prices, emissions, allowance distribution (2009-present, US Northeast)
California Cap-and-Trade	Auction settlement prices, emissions, auction volumes (2013-present)
ICAP Allowance Price Explorer	Curated cross-ETS prices (20+ jurisdictions globally)
World Bank Carbon Pricing Dashboard	Global carbon pricing: taxes + ETS (70+ initiatives)
RFF World Carbon Pricing Database	National historical coverage to 2023 (Dolphin, Pollitt, Newbery 2020)
Emissions-weighted carbon price (ECP)	Effective carbon prices and coverage by jurisdiction, sector, and region
Berkeley VROD	Voluntary market aggregator (Verra, Gold Standard, ACR, CAR, ART TREES)
CarbonPlan OffsetsDB	Voluntary market aggregator, parquet snapshots

All sources are free. Two need extra steps: the World Bank dashboard blocks programmatic clients, so co2_world_bank() takes a manually downloaded file, and full World Carbon Pricing Database downloads now need a token requested from the publisher (the derived ECP data behind co2_ecp_prices() stays open).

Quick start

library(carbondata)

# All supported markets at a glance
co2_markets()

# Latest EU ETS auction prices
prices <- co2_euets_price(from = "2024-01-01")
head(prices)

# Verified emissions for German installations, 2022
emissions <- co2_euets_emissions(country = "DE", year = 2022)

# Cross-market price comparison
icap <- co2_icap_prices(jurisdiction = c("EU ETS", "UK ETS", "RGGI"))

# Voluntary offset projects across five registries
vrod <- co2_vrod()

Example: the cross-market price chart

One chart, four compliance markets, two decades of data.

library(carbondata)

icap <- co2_icap_prices(
  jurisdiction = c("EU ETS", "UK ETS", "RGGI", "California")
)

plot(icap$date, icap$price, col = factor(icap$jurisdiction),
     xlab = "", ylab = "Price per tCO2e (local currency)", pch = 20)
legend("topleft", legend = levels(factor(icap$jurisdiction)),
       col = seq_len(nlevels(factor(icap$jurisdiction))), pch = 20)

Short names such as "EU ETS" and "RGGI" resolve to the full names ICAP uses. Call co2_icap_systems() to see every system with its date range.

Example: voluntary vs compliance divergence

Compliance allowances trade far above nature-based voluntary credits. The two datasets make the gap easy to quantify.

# EU ETS average auction price, 2024
eu <- co2_euets_price(from = "2024-01-01", to = "2024-12-31")
mean(eu$price_eur, na.rm = TRUE)

# Issuances across Verra forestry projects
vrod <- co2_vrod()
forestry <- vrod[vrod$`Voluntary Registry` == "VCS" &
                   vrod$Scope == "Forestry & Land Use", ]
summary(forestry$`Total Credits Issued`)

Registry codes are VCS (Verra), GOLD, ACR, CAR, ART, and ISO. Column names come straight from the workbook, with wrapped headers flattened: the sheet stores one column as "Total Credits \r\nIssued", which carbondata normalises to "Total Credits Issued".

A trap worth knowing about: EU ETS2

From compliance year 2024, DG CLIMA publishes the new EU ETS2 (buildings, road transport, small industry) in the same file as the original ETS1 installations, as one aggregate account per member state. Those 25 accounts added 981 Mt to the 2024 file, about 45% of the reported total, so summing the file as published roughly doubles country totals.

carbondata separates them. The default is ETS1, which is what “EU ETS” has always meant:

co2_euets_emissions(country = "DE", year = 2024)                   # ETS1 only
co2_euets_emissions(country = "DE", year = 2024, scheme = "ets2")  # ETS2 accounts
co2_euets_emissions(country = "DE", year = 2024, scheme = "all")   # both, do not sum

Functions

EU ETS (EEA / EUTL)

Function	What it returns
`co2_euets_emissions()`	Verified emissions by installation and year
`co2_euets_allocations()`	Free allowance allocations
`co2_euets_surrendered()`	Surrendered units for compliance
`co2_euets_price()`	EUA auction settlement prices
`co2_euets_installations()`	Installation registry (2012 snapshot, historical)
`co2_euets_files()`	DG CLIMA file vintages available

Other compliance markets

Function	What it returns
`co2_ukets()`	UK ETS verified emissions and surrenders
`co2_ukets_allocations()`	UK ETS free allocations (installations or aviation)
`co2_rggi_allowances()`	RGGI allowance distribution by state
`co2_rggi_state_proceeds()`	RGGI cumulative auction proceeds by state
`co2_california_prices()`	California Cap-and-Trade auction settlement prices
`co2_california_caps()`	California overall caps by vintage

Cross-market aggregators

Function	What it returns
`co2_icap_prices()`	ICAP Allowance Price Explorer (multi-ETS prices)
`co2_icap_systems()`	ICAP systems with date ranges and observation counts
`co2_world_bank()`	World Bank Carbon Pricing Dashboard (manual download)
`co2_rff_pricing()`	RFF World Carbon Pricing Database (frozen at v2025.0.0)
`co2_ecp_prices()`	Emissions-weighted carbon prices and coverage

Voluntary markets

Function	What it returns
`co2_vrod()`	Berkeley VROD (5 registries aggregated)
`co2_offsets_db()`	CarbonPlan OffsetsDB parquet snapshots
`co2_cad_trust()`	Climate Action Data Trust (not supported, see below)

Helpers

Function	What it returns
`co2_markets()`	Directory of supported markets
`co2_clear_cache()`	Empty the local cache
`co2_cache_info()`	Show cached files

Source availability

Carbon market publishers move files without notice, so this package tracks source health explicitly. As of August 2026:

World Bank Carbon Pricing Dashboard: the host rejects non-browser clients (HTTP 403 regardless of user agent). Download the file in a browser and pass it: co2_world_bank(path = "~/Downloads/data_08_2025.xlsx"). The function reports the current URL when the automatic fetch fails.
RFF World Carbon Pricing Database: left GitHub on 30 May 2026. co2_rff_pricing() reads the last openly published release, v2025.0.0. For newer vintages request a token from the publisher, or use co2_ecp_prices(), which stays open and updates with each release.
CarbonPlan OffsetsDB: daily publishing became irregular during 2026, with the last snapshot seen on 1 June 2026. co2_offsets_db() walks back to find the newest available and warns when it is more than a fortnight old.
Climate Action Data Trust: no unauthenticated public API. co2_cad_trust() errors with guidance on self-hosting or requesting partnership access.
EU ETS installation registry: DG CLIMA’s only bulk registry file is a snapshot dated 28 August 2012. co2_euets_installations() warns on every call. For current installation detail, use the identifiers on co2_euets_emissions().

A weekly GitHub Actions canary exercises every source and opens an issue when one breaks. Run it yourself with:

Rscript inst/canary/check-endpoints.R

Caching

Downloads are cached to tools::R_user_dir("carbondata", "cache") by default. Subsequent calls are instant. Override the location with options(carbondata.cache_dir = "/path/to/dir"). Use co2_clear_cache() to remove cached files.

Files that update in place under a stable name (the ICAP price feed, the current-year EEX auction report) carry a one-day cache limit so a stale copy is not served indefinitely. Everything else is cached until you pass refresh = TRUE.

Package	Description
cer	Australian Clean Energy Regulator (ACCUs, Safeguard, NGER)
aemo	Australian Energy Market Operator (NEM prices, dispatch)
climatekit	Climate indices (temperature, precipitation, drought)
readnoaa	NOAA climate and weather data
inflationkit	Inflation analysis (real-terms carbon prices)
carbonr	Carbon footprint calculator (activity → tCO2e conversion)

Issues

Report bugs or request features at GitHub Issues.

Keywords

carbon markets, emissions trading, EU ETS, UK ETS, RGGI, California Cap-and-Trade, Verra, Gold Standard, ICAP, World Bank carbon pricing, voluntary carbon markets, climate finance, CO2, greenhouse gas, sustainability disclosure, TCFD, CSRD, SFDR, ISSB

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