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Hi all! I am a third year student at UC Berkeley that has worked with Effective Altruism for about a year now. Under the direction of @Robert Van Buskirk  (founder of Solar4Africa.org), myself and fellow Berkeley student Sam Miller have been working on an EA-related project that deals with Solar4Africa’s solar-electric cooking systems; our project is concerned with the overall refinement of the intervention and the cost-effectiveness of the cooking systems. The purpose of this post is to broadly explain our intervention and its relevance to the EA community, as well as introduce the methodology that we plan to use throughout the project. Please note that any sort of feedback/comments would be greatly appreciated!

General Description of Intervention

Solar4Africa’s Project #4 aims to assess the possible humanitarian benefits that the adoption of long-lasting solar electric cooking systems has on communities in rural Malawi. By replacing biomass sources such as firewood or crop residue for cooking, offgrid solar electricity provides the opportunity for cleaner, cheaper and longer-lasting energy. Furthermore, due to extremely deflated prices in rural Malawi, cash transfers or subsidized solar energy systems can generate substantial economic revenue for beneficiaries.

Solar4Africa Project #4’s goal is to provide and distribute philanthropically-supported offgrid cooking systems to women’s groups and households that are efficiently subsidized so that they generate benefits that far outweigh the initial cost of the cooking system and where philanthropic subsidies are cost-effective from an EA perspective. To do this the cooker systems are designed to last from 5 to 15 years due to their long lasting solar panels and specialized batteries, thus generating large sums of consumption income and health benefits over the system lifetime. 

Some clean cooking projects are starting to use carbon credit finance as a means of providing cash transfers to households that are using clean cooking technologies. The poverty-reduction benefits of the cash transfers justify a higher carbon credit price because of the non-climate co-benefits of the project that they create. Solar4Africa is considering using a similar approach where the revenues from carbon finance are used co-finance poverty-reduction and health benefits. If the cost of clean cooking can be justified based on multiple benefits, then the amount of finance that is cost-effective is more than what can be justified from the consideration of only one type of benefit. 

Health Benefits

In rural areas of Malawi there is almost a universal use of biomass for cooking, leading to poor air quality within households and overexposure to carbon monoxide (CO) and particulate pollution. According to This journal article, cooking methods with improved combustion efficiency (compared to open fires) are able to reduce harmful emissions by anywhere from 75% to 90% in Malawi, which is a significant improvement. Using this VizHub data, we can see that lower-respiratory infections in Malawi has a disease burden of 2,779 DALYs per 100,000 people per year. This means that the respiratory disease burden for 5 people over five years will be: (2,779)x(5 people x 5 years)/100,000 = 0.695 DALYs. Using the above journal’s optimistic estimates of emission reductions, let’s say that Solar4Africa’s solar electric cookers decrease respiratory disease by 30%. It could potentially generate a health benefit of: 30% x 0.695 = 0.2085 DALYs for 5 people over 5 years. 

While there is a real possibility that Solar4Africa’s solar electric cookers will have health benefits for long-term users, we acknowledge that organizations have been critical of previous claims of the health impacts of improved cooking. Though we note that Solar4Africa’s intervention is not an improved biomass stove, but an off-grid solar electric stove which is quite different. For improved biomass stoves, this GiveWell report finds that improved cookstoves may have “limited impacts on women’s health and no clear impacts on children’s health under typical use.”  Specifically, the GiveWell evaluation notes: “Distributions of clean [biomass] cookstoves may have been less effective than expected due to implementation challenges, such as low compliance with using the replacement stoves and failure of the cleaner stoves to reduce air pollution sufficiently.” 

Monetary Benefits

Health benefits are not the only positive of adapting solar cookers. This article discusses the monetary benefits of solar cookers. The discussion notes that “[S]olar panels that provide direct digital synthesis (DDS) electricity can last 20 years or more, and lithium-titanium-oxide (LTO) batteries have a life cycle of 10,000 cycles or more.” This incredibly long life span of a single solar cooker has enabled solar panels to be as —if not more -– cost effective than wood burning stoves in the long term. However, several barriers remain which inhibit solar electric cookers from completely being more cost effective than wood cookers. Firstly, low-cost wood cookers (meaning when wood efficiencies are high, fuel is inexpensive, and quality of fuel is high) outperform solar electric cookers in terms of cost. Secondly, in order for solar electric cookers to be as cost effective as possible, a low cost approach of efficiently importing and distributing batteries must be implemented. We do believe, however, that the implementation of long-lasting solar electric cookers will generate a great amount of benefit for the beneficiaries (see cost-effectiveness calculation methodology below).

One related EA post titled “Soaking Beans–a cost-effectiveness analysis” provides an estimate of the potential benefits that soaking beans would have. This post is one of the few documents that addresses an improved cooking intervention in Africa from an EA perspective. 

In the post, the author notes that beans make up an estimated 25 percent of an average Ugandan’s calorie intake and 40 percent of their daily protein intake. Beans have a large cooking time, which means that lots of wood and charcoal is required in the cooking process. The analysis states that soaking beans could reduce the cooking time by 20-50 percent, thereby reducing the amount of wood and charcoal used. The analysis takes into consideration a variety of benefits from a shorter cooking time, including reduced CO2 emissions from charcoal and wood burning, and monetary savings. If one percent of the Ugandan population started soaking beans, the reduction in CO2 emissions totals at 76,249 tons. Due to Ugandan’s decreased expenditures on wood and charcoal (not as much wood and charcoal would be needed due to the shorter cooking time) the analysis estimates that roughly 1.5 million dollars (U.S.) would be saved if 1 percent of the Ugandan population started soaking beans.

There is another EA post  titled “Clean cookstoves may be competitive with GiveWell-recommended charities” that models the intervention of clean cookstoves. Their model considers the implementation of clean cookstoves and focuses primarily on its health benefits; this is different from our intervention because we plan to generate long-lasting benefits that accrue both monetary and health benefits over time. Using their own cost effectiveness model, the EA post finds that there is the possibility of cost-per-life-saved of $11,800. The post acknowledges the challenges that clean cookstove interventions pose, citing “We are aware that J-PAL has reviewed this question some time ago and concluded that this is difficult. More recently IDinsight considered this topic and found that it can be made to work.” 

Cost-effectiveness Estimation Methodology

The cost-effectiveness calculations that we plan to follow will be an adaptation of what is provided at this EA post. In this post, Robert lays out a simplified version of how we will be able to calculate marginal cost effectiveness as an inverse of marginal cost of unit of impact. The data that we will use to assess the cost effectiveness of Project #4 will be derived from (a) the 2019 Global Burden of Disease data, which is synthesized to estimate mortality, health outcomes, and risks of various diseases across the globe in DALYs and YYLs, and (b) data from Solar4Africa activities and demonstration tests.


We are very excited to continue Solar4Africa’s Project #4 throughout the year, and plan to upload a follow-up post in the next month or so regarding our progress and cost-effective analysis. As previously mentioned, any comments, suggestions or criticisms would be highly appreciated. Thanks!


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Executive summary: Solar4Africa Project #4 aims to provide long-lasting solar electric cooking systems to rural communities in Malawi, generating significant health improvements and cost savings over the systems' lifetimes.

Key points:

  1. Replacing wood/biomass cooking with solar electric systems can reduce harmful emissions by 75-90% and respiratory disease burden by an estimated 30% over 5 years for each household.
  2. Solar electric cooking systems can last 10-20 years, leading to major cost savings compared to purchasing wood/biomass fuel.
  3. Health and monetary benefits over the lifetime of the solar systems are used to estimate cost-effectiveness based on cost per unit of impact.
  4. Barriers remain for solar electric systems to outperform wood stoves in terms of upfront cost, requiring efficient distribution of low-cost, long-lasting batteries.
  5. Related research has found clean cookstoves can generate significant health benefits and carbon emission reductions, though long-term adherence is a challenge.
  6. Further analysis is planned using Global Burden of Disease data and Solar4Africa field data to refine cost-effectiveness estimates.


This comment was auto-generated by the EA Forum Team. Feel free to point out issues with this summary by replying to the comment, and contact us if you have feedback.

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