Investments in this strategy aim to offer improved alternatives for cooking – in particular, clean cookstoves – to reduce health risks associated with household air pollution, decrease time needed to collect wood or charcoal, prevent unnecessary deforestation, and limit harmful emissions. The sections below include an overview of the strategy for achieving desired goals, supporting evidence, core metrics that help measure performance toward goals, and a curated list of resources to support collecting, reporting on, and using data for decision-making.


Dimensions of Impact: WHAT

Investors interested in deploying this strategy should consider the scale of the addressable problem, what positive outcomes might be, and how important the change would be to the people (or planet) experiencing it.

Key questions in this dimension include:

What problem does the investment aim to address? For the target stakeholders experiencing the problem, how important is this change?

Many people in emerging-market countries have limited access to modern energy, and continue to rely for cooking on traditional biomass fuels like wood, coal, crop waste, and dung for cooking (3). Such fuels often fail to burn completely on indoor stoves, leading to emissions of air pollutants like carbon monoxide, nitrogen oxide, benzene, formaldehyde, and fine particulate matter. These pollutants can cause health risks, including acute respiratory infections, lung diseases, lung cancers, and low birth weight—in addition to the environmental harm caused by greenhouse gas emissions. Improved alternatives for cooking can reduce end beneficiary dependence on traditional biomass fuels such as wood or charcoal, thereby helping people and the environment by:

  • reducing health risks and negative health outcomes as a result of decreased household air pollution (4);
  • reducing the amount of time end users (typically women and children) spend gathering biomass for household use, making time available for income generation, education, and leisure (5);
  • reducing emissions of black carbon, the second-largest contributor to climate change after CO2 (1); and
  • limiting deforestation and soil erosion by lowering user dependence on cut-down trees for burnable wood in areas with short supply of other biomass.

Interested in understanding how gender relates to this strategy? Check out the gender lens summary and metrics created to complement this strategy: Improving Women's Empowerment through Clean Cookstoves.

What is the scale of the problem?

Over three billion people in emerging-market countries have limited access to modern energy, and continue to rely on traditional biomass fuels for cooking (4). As of 2012, the World Health Organization (WHO) estimated that over four million people die prematurely each year from illnesses related to household air pollution caused by cooking stoves, and more than half of premature deaths due to pneumonia among children under five are caused by particulate matter (soot) inhaled from household air pollution (4). Burning biomass also emits black carbon (1). The WHO estimates that cooking with biomass accounts for 18% of global greenhouse gas emissions; in emerging-market countries, about 730 million tons of biomass are burned every year, emitting one billion tons of carbon.


Dimensions of Impact: WHO

Investors interested in deploying this strategy should consider whom they want to target, as almost every strategy has a host of potential beneficiaries. While some investors may target women of color living in a particular rural area, others may set targets more broadly, e.g., women. Investors interested in targeting particular populations should focus on strategies that have been shown to benefit those populations.

Key questions in this dimension include:

Who (people, planet, or both) is helped through investments aligned with this Strategic Goal?

While this strategy has many potential end users, the following groups are the primary users of traditional cooking fuels and are more often targeted:

Women and Children: Women and children are disproportionately vulnerable to dirty cookstoves than other demographics. In emerging countries, women and children who assume the responsibility for cooking spend several hours each day breathing in close proximity to smoky cookstoves, leaving them susceptible to respiratory infections and disorders.

People in Rural Communities: Individuals in poor, rural communities often have limited access to cleaner fuels or electricity for cooking. They may also struggle to afford to purchase improved, cleaner cookstoves and may have limited access to healthcare that could help mitigate the effects of dirty cookstoves.

In addition, this strategy can target Climate Change and Pollution: since black carbon emissions from burned biomass remain in the atmosphere for only a limited time, and because black carbon contributes heavily to climate change (CO2) (1), controlling the use of biomass energy could limit warming effects on the atmosphere relatively quickly.

What are the geographic attributes of those who are affected?

Most individuals without adequate alternatives for cooking at home reside in rural areas (2). Indoor air pollution takes the heaviest toll in South Asia and sub-Saharan Africa, where both rural and suburban populations primarily rely on biomass for energy needs.


Dimensions of Impact: CONTRIBUTION

Investors considering investing in a company or portfolio aligned with this strategy should consider whether the effect they want to have compares to what is likely to happen anyway. Is the investment's contribution ‘likely better’ or ‘likely worse’ than what is likely to occur anyway across What, How much and Who?

Key questions in this dimension include:

How can investments in line with this Strategic Goal contribute to outcomes, and are these investments’ effects likely better, worse, or neutral than what would happen otherwise

Project evaluations have shown highly variable uptake of new cookstove models, with more uptake for models that are functionally similar to traditional cookstoves and that can address gaps in the functionality of traditional cookstove designs, among other factors. The extent to which this strategy can improve alternatives used for cooking at home depends on the specific investee business and the product they are bringing to market. For this strategy, increasing access to cleaner and better-designed cookstoves will likely lead to better short-term outcomes, particularly in terms of emissions and environmental impact, than what would happen without the investment.

How Much

Dimensions of Impact: HOW MUCH

Investors deploying capital into investments aligned with this strategy should think about how significant the investment's effect might be. What is likely to be the change's breadth, depth, and duration?

Key questions in this dimension include:

How many target stakeholders can experience the outcome through investments aligned with this Strategic Goal?

The potential breadth of impact depends on the number of individuals in emerging markets who lack access to clean, well-designed cookstoves – a total estimated at roughly three billion people worldwide – and who are still reliant on traditional means of meal preparation (4).

How much change can target stakeholders experience through investments aligned with this Strategic Goal?

The amount of change end users derive from this strategy depends on the context, the product delivered, the product being replaced, and the nature of the clients’ use of the product. Examples of change aligned with this strategy include:

  • Studies in Peru, Mexico, and Honduras found that improved cookstoves decreased household exposure to air pollutants, with a 70.5–74% reduction in kitchen concentrations of particulate matter and a 35–63% reduction in personal exposure (6, 7, 8).
  • In India, an analysis of survey data significantly associated household use of high-pollution fuels (especially coal and kerosene) with increased odds of low birth weight and neonatal death (9).
  • A lab- and Honduras-based field trial found that improved cookstoves reduced particulate-matter emissions factors in all cases, with an average emissions reduction of 70% (10).

Illustrative Investment

Inyenyeri, a company based in Rwanda, leases high-tech, energy-efficient cookstoves at the low cost of USD 7 per year to urban customers. These customers then buy the company’s proprietary clean fuel pellets to replace traditional fuels. Rural customers can use the stoves for free in exchange for collecting the raw materials used to manufacture the fuel pellets. Because the raw materials-to-pellets ratio is designed in their favor, rural customers spend fewer total hours collecting biomass compared to before using the clean cookstove, which makes additional time available for income generation and education. For urban customers, the cost of cooking with Inyenyeri’s stoves is comparable to cooking with charcoal, a non-sustainable fuel with limited supply that fluctuates in price with demand. Rather than simply providing stoves, Inyenyeri works to understand what motivates the adoption of cookstoves in emerging countries. It also helps with the transition to cleaner stoves by providing free bicycle delivery, free training prior to delivery, and free cooking classes. If a stove breaks or is stolen, Inyenyeri replaces it at no cost (11).

Draw on Evidence

This mapped evidence shows what outcomes and impacts this strategy can have, based on academic and field research.

The State of the Global Clean and Improved Cooking Sector

Putti, Venkata Ramana, Michael Tsan, Sumi Mehta, and Srilata Kammila. “The State of the Global Clean and Improved Cooking Sector.” (2015).

Intra-Household Externalities and Low Demand for a New Technology: Experimental Evidence on Improved Cookstoves

Miller, Grant, and A. Mushfiq Mobarak. Intra-Household Externalities and Low Demand for a New Technology: Experimental Evidence on Improved Cookstoves.” Unpublished manuscript (2011).

Kerosene: A Review of Household Uses and their Hazards in Low- and Middle-Income Countries

Lam, Nicholas L., Kirk R. Smith, Alison Gauthier, and Michael N. Bates. “Kerosene: A Review of Household Uses and their Hazards in Low- and Middle-Income Countries.” Journal of Toxicology and Environmental Health, Part B 15, no. 6 (2012): 396-432.

A Comparative Risk Assessment of Burden Disease and Injury Attributable to 67 Risk Factors and Risk Factor Clusters in 21 Regions, 2990 - 2010: A Systematic Analysis for the Global Burden of Disease Study 2010.

Lim, Stephen S., Theo Vos, Abraham D. Flaxman, Goodarz Danaei, Kenji Shibuya, Heather Adair-Rohani, Mohammad A. AlMazroa et al. “A Comparative Risk Assessment of Burden of Disease and Injury Attributable to 67 Risk Factors and Risk Factor Clusters in 21 Regions, 1990–2010: A Systematic Analysis for the Global Burden of Disease Study 2010.” The Lancet 380, no. 9859 (2013): 2224-2260.

A Laboratory Comparison of the Global Warming Impact of Five Major Types of Biomass Cooking Stoves.

MacCarty, Nordica, Damon Ogle, Dean Still, Tami Bond, and Christoph Roden. “A Laboratory Comparison of the Global Warming Impact of Five Major Types of Biomass Cooking Stoves.” Energy for Sustainable Development 12, no. 2 (2008): 56-65.

Each resource is assigned a rating of rigor according to the NESTA Standards of Evidence.

Define Metrics

Core Metrics

This starter set of core metrics — chosen from the IRIS catalog with the input of impact investors who work in this area — indicate performance toward objectives within this strategy. They can help with setting targets, tracking performance, and managing toward success.

Additional Metrics

While the above core metrics provide a starter set of measurements that can show outcomes of a portfolio targeted toward this goal, the additional metrics below — or others from the IRIS catalog — can provide more nuance and depth to understanding your impact.