Barbara Haya

Analysis of projects generating 80% of total offset credits issued by ARB under its U.S. Forest projects offset protocol shows that 82% of the credits generated by these projects likely do not represent true emissions reductions, due to the protocol’s leakage accounting methods. The total quantity of over-crediting across these 36 projects equals approximately 80 million tons of CO2. For context, the U.S. Forest Protocol has generated 80% of the offset credits in California’s cap-and- trade program; the estimated over-crediting is equal to one third of the total expected effect of California’s cap-and-trade program on emissions during 2021-2030.

Because of problems created by the incentive structure for carbon offsets as a mode of climate mitigation, companies should switch to a “contributions” framing to preserve a crucial flow of climate investment.

Cookstove carbon offset projects can progress multiple Sustainable Development Goals (SDGs), including climate, energy, health, gender, poverty and deforestation. However, project emission reductions must be accurately or conservatively estimated to avoid undermining climate action and long-term SDG financing. Here we conduct a comprehensive, quantitative, quality assessment of offsets by comparing five cookstove methodologies with published literature and our own analysis. We find misalignment, in order of importance, with fraction of non-renewable biomass, firewood–charcoal conversion, stove adoption, stove usage, fuel consumption, stacking (using multiple stoves), rebound and emission factors. Additionality, leakage, permanence and overlapping claims require more research. We estimate that our project sample is over-credited 9.2 times. Gold Standard’s metered methodology, which directly monitors fuel use, is most aligned with our estimates (1.5 times over-credited) and has the largest potential for emission abatement and health benefit. We provide recommendations to align methodologies with current science and SDG progress.

You can find a summary of our findings, specific guidance for credit buyers and project developers, along with a list of quality cookstoves offset projects here: https://gspp.berkeley.edu/research-and-impact/centers/cepp/projects/berkeley-carbon-trading-project/cookstoves

Carbon offsets are widely promoted as a strategy to lower the cost of emission reductions, but recent findings suggest that offsets may not causally reduce emissions by the amount claimed. In a compliance market, offsets increase net emissions if they do not reflect real emission reductions beyond the baseline scenario. Few studies have examined the additionality of forest carbon offsets within California’s U.S. Forest Projects compliance offset protocol, one of the largest forest offset programs in the world. Here we examine additionality in California’s offset protocol. Since 2012, most of California’s offset credits (84%) have been awarded to improved forest management projects. Using a database of improved forest management project characteristics, locations, and remotely sensed forest disturbance data indicative of management activity, we find that projects have been primarily allocated to forests with high carbon stocks (127% higher than regional averages) and low historical disturbance (28% less disturbance than regional averages since 1985). A matching and panel regression analysis failed to show additionality, as project creation did not significantly lower disturbance rates 3 and 5 years after project implementation relative to similar non-project lands. These results indicate that California’s forest offset protocol may contribute to an increasingly large carbon debt.

Reducing Emissions from Deforestation and Forest Degradation (REDD+) is the project type with the most credits on the voluntary carbon market—about a quarter of all credits to date. REDD+ projects pay governments, organizations, communities, and individuals in forest landscapes (primarily tropical ones in the Global South) for activities that preserve forests and avoid forest-related greenhouse gas (GHG) emissions.

This study brings together an interdisciplinary team of political and natural ecologists and ecosystem modelers to comprehensively assess the quality of these credits. We assess their effectiveness at reducing deforestation, generating high-quality carbon credits, and protecting forest communities focusing on five key program elements: baselines, leakage, forest carbon accounting, durability, and safeguards.

As with other major offset project types, we found that current REDD+ methodologies likely generate credits that represent a small fraction of their claimed climate benefit. Estimates of emissions reductions were exaggerated across all quantification factors we reviewed when compared to the published literature and our independent quantitative assessment. Safeguard policies, presented as ensuring “no net harm” to forest communities, in practice have been treated as voluntary guidance. 

When considering all evidence together, our overall conclusion is that REDD+ is ill-suited to the generation of carbon credits for use as offsets. We suggest a number of other measures that private actors can take or support that together can help to reduce tropical deforestation.  

Improved forest management (IFM) has the potential to remove and store large quantities of carbon from the atmosphere. Around the world, 293 IFM offset projects have produced 11% of offset credits by voluntary offset registries to date, channeling substantial climate mitigation funds into forest management projects. This paper summarizes the state of the scientific literature for key carbon offset quality criteria—additionality, baselines, leakage, durability, and forest carbon accounting—and discusses how well currently used IFM protocols align with this literature. Our analysis identifies important areas where the protocols deviate from scientific understanding related to baselines, leakage, risk of reversal, and the accounting of carbon in forests and harvested wood products, risking significant over-estimation of carbon offset credits. We recommend specific improvements to the protocols that would likely result in more accurate estimates of program impact, and identify areas in need of more research. Most importantly, more conservative baselines can substantially reduce, but not resolve, over-crediting risk from multiple factors.