February 17, 2024 Friends & Family Letter


Pumps, cookers, cheap off-grid electricity, effective altruism students and summer plans.

Dear Friends, Family and compatriots:

  Well it has been too long since my last letter in September ... time to give an update ... this letter is very long and is going to cover finances, solar pumps, cookers, cheap off-grid electricity, student cost-effectiveness research, and next summer's plans.

  But let me start with a quick summary of these six key developments


  We now have a new non-profit fiscal sponsor (omprakash.org) And we have raised about $80k in donations in the last four months through our new fiscal sponsor (Thank you! Thank you! Thank you! everybody!). Note that more than half of these funds have been provided by one super-generous donor (Thank you soo soo much Eric  ... without you we would be doing half as much as we are doing now!)  

  With the resources that we now have, we will now be able to distribute more than 500 solar pumps next summer, AND we are able to continue work on cookers, lights, solar car experiments, etc. and sustain a network of 16 village solar shops run by local women's collectives!

  We do this with about $100k/year from donors like you. About $100k/year from UK Aid and more than $100k/year collected from our rural customers in the form of discounted solar product sales.


  More than 900 solar pumping systems were distributed in 2023 (Yeah!) And small farmers spent about $100k of their hard-earned money to buy nearly 200 kilowatts of solar panels (i.e. the equivalent of 2000 100W solar panels)


  With support from UK Aid, we have now received more than 1800 additional solar electric cookers in Malawi. We will be distributing these cookers over the coming year. We now have THE MOST COST-EFFECTIVE off-grid solar electric cooking system in the world. We are going to try to use this status (wish us luck!!) to organize and instigate some larger scale projects to get solar electric cooking to hundreds of thousands of rural Africans over the coming years.  We do this by formulating new proposals and grant applications that can pay for future, larger-scale programs and initiatives.


  International solar panel prices have recently dropped 30% to 50%. We are now able to get price quotes of less than 10 cents/watt at the factory door price of solar panels. This price is about 50% lower than the price that we were getting for such panels just last year! This means that it might be possible to get solar panels to Africa for $0.15/W.  The result is that a 330W solar panel can cost as little as $50 delivered to Malawi!.  At full utilization, a 330W panel can product 1kWh/day.  This means at full utilization, the amortized solar panel cost of solar electricity is $50/(10x365) = $0.014/kWh when amortized over 10 years!!!  Theoretically therefore, the solar electrification of rural Africa is now potentially affordable for even the hundreds of millions of rural Africans who earn less than $1/day!!


  Since my last letter, I have mentored a batch of UC Berkeley students during the Fall 2023 semester and had them do development cost-effectiveness analyses from an "Effective Altruism" perspective. Effective altruists try to channel their donations to the charities that are most cost-effective as indicated by data and quantitative analysis. 

  You can see some of the analyses posted here:



  We are going to do another push to expand our impact next summer by increasing the cost-effectiveness of the work that we do and taking the measurements and data that help estimate our performance.  We have therefore created and posted a set of volunteer internship positions that people can apply to if they want to volunteer with us next summer in Malawi.  If you want to volunteer next summer, you go to the following link:https://www.omprakash.org/global/solar4africa/apply and click on the box that says "View Our Current Positions."

Describing The Six Developments in Detail

  I will next go into some detail on these six developments. There are two reasons for providing the extra detail: (A) To provide additional information for those who are interested, and (B) To document progress for the "historical record" so that an analysis of methods and results can be done at a later date.

(1) Setting up with a new fiscal sponsor

  Last summer, a good friend of mine (John W) who is also retired, visited the Malawi projects.  He fell in love with the work. This is easy to do because when you see how happy people can get when they can double their irrigated garden size (and income) with a solar pump, their happiness is pretty darn contagious. And when you see such happiness first hand, naturally you want to create more of it.

  Our old non-profit sponsor just did not have the bandwidth to help us get much bigger, so John set out to find a new non-profit fiscal sponsor. He found a GREAT one: omprakash.org.  Omprakash specializes in hosting a supportive network of grassroots partner organizations all around the world. They have 168 partner organizations in 57 countries, and it was a great fit for us to join their network.

  You can now see our Omprakash partner page at:


  The other cool thing about this fiscal sponsor is that they have a nice automated system for tracking donations and spending, so that anyone can click through and see the details of how the donated funds are being spent.

  As mentioned above, we have raised about $80k since the beginning of November.  About half of this amount is needed to support our solar electric cooking activities, and about half can be dedicated to solar pumps. This is enough to distribute another 400 to 600 solar pumping systems next summer, and to support the distribution of 1800 solar electric cookers that were purchased using grant funds from UK Aid.  More details on these activities below ...

(2) Progress with Solar Pumps

  The hugely important result from our solar pump distribution last summer is the fact that we were able to verify that large numbers of low-income customers can pay at least half of the cost of the systems.  This is enough to pay for the solar panels. Customers paid in total $100K for solar panels last summer which was enough to buy 2000 100W solar panels. 

  Another key development is that we started the process of collecting detailed data on pump use and impacts.  This is in an effort to estimate how many dollars of benefit accrue as a result of the donor support that this effort receives. John wrote up a nice report on our first estimates in this regard which can be found here:


  Our current preliminary estimate is that the solar pumps can produce $20 to $30 of new income per $1 donated if the pumps are used well over 3 to 5 years. 

  One of our next steps is to add power meters to all of the new pumps and to tighten up our data collection for all customers so that we can verify what the benefits are likely to be for all customers on average. 

  An additional step is to increase the capacity of the solar panel, the size of the pump, and the length of the irrigation pipe to see if customers can increase the irrigated garden area and income generation by a factor of 2 to 5.  In this way, I am hoping that we come up with a solar pumping distribution scheme that can produce $50 to $100 of new income for low-income Malawian farmers for every $1 of donor support that we can get. Fingers crossed!!

(3) Progress with Solar Cookers

  Last month we received a shipment of 1800 solar electric cookers that was purchased using a grant from the UK-Aid-supported Modern Energy Cooking Services (MECS) program (See: https://mecs.org.uk/). Purchase and shipping of the cookers cost about $50K (i.e. about $30/cooker), but then the Malawi government charged us 50% import tax to bring them into the country (ouch!).  We applied to the Treasury Ministry for a tax exemption because we are distributing the cookers to low-income rural households that really need them, but not surprisingly we were denied. 

  We are now creating a non-profit local Malawi NGO called Affordable Solar for Villagers, and we hope that we can do tax-free import of the cookers for the villagers with the new NGO in the future. We will see ...

  Notice that because of the pump distribution last summer and other distributions that we have, we now have more than 1000 customers who have more than 200 watts of solar panels each.  That means that each of these customers now has enough solar panels to run the solar cookers if they want. 

   We have also done the measurements and have verified that for every kWh of solar electric cooking that people do, they save between 2 and 7 kilograms of wood that would have been burnt had they cooked the food on wood or charcoal. Some of that saved wood results in increased tree growth and decreased deforestation.  In Malawi, about 1/3 of saved wood is estimated to be "unsustainably harvested" on average. This means that one kWh of cooking theoretically results in between 0.7 to 2.3 kg of reforested wood and approximately 1.1 to 3.7 kg of CO2 sequestration. So when women in Malawi use solar electric cookers, the whole planet benefits. 

  We have therefore set up a fundraising campaign to support the village women's solar shops in doing demonstration cooking with solar electric cookers for their communities. You can donate to that campaign here:


  I personally am going to start "offsetting" the emissions from my plane travel by donating $100 to this campaign for every ton of CO2 emissions that I am responsible for. Implicit in this "offsetting" equation is the assumption that for every kWh of demonstration solar electric cooking that is done, 2 to 5 kWh of uncompensated solar electric cooking will occur. I'll keep an eye on the ratio of compensated vs. uncompensated cooking as the project progresses.

  Roughly, emissions from air travel are about one ton of CO2 for every 10,000 miles. Note that round trip travel from California to Malawi is about 35,000 miles. So, I owe about $100 x 3.5 tons = $350 for the climate damage of my next trip to Malawi. I have donated $250 to this campaign, so I owe $100 more.

  I don't have a car, but given all of the air travel that I do, I am probably responsible for about 20 tons of CO2 emissions per year. I am about average for the US.  Total US emissions are 6.3 billion tons of CO2 equivalent per year, and the population is 330 million, so the average is 6300M/330M = 19 tons of CO2/person/year. 

  But the ~20 tons/year is only our current GHG emissions.  Over history the US has emitted more than 200 billion tons of GHG gases that are still in the atmosphere, heating up the planet. That is about 600 tons per person of what we might call our "climate debt."  So, I will probably start donating $300month to offset about 3 tons/month or 36 tons/year. If I can start flying less and get my emissions down to 16 tons/year and then 20 tons/year can be paid towards my "climate debt."  This way, I can pay off my climate debt in only 30 years!  Anyways, all of this greenhouse gas accounting warrants a longer, more detailed discussion that I will put off to a later time. 

(4) Solar Panels at 10 cents/watt!

  About three years ago, I published a technical report that said that factory door solar panel prices would decline "to a range of $0.10/Wp to $0.15/Wp." See:


  Well the other day, I was shopping on Alibaba.com and I saw some listings for solar panels at $0.10/watt.  I did not believe them at first, but I thought that I would ask for a quote. I got the quote and found that the offer was real.

  Fortunately, Malawi allows for tax-free import of solar panels. This means that when solar panels are $0.10/watt at the factory door, it is generally possible to get the solar panels to Malawi for just shipping and logistics costs which can be as low as $0.05/watt. This means that the delivered cost of solar panels to Malawi can now be as low as $0.15/watt.

  The result is that a 330W solar panel can cost as little as $50 delivered to Malawi!.  At full utilization, a 330W panel can product 1kWh/day.  this means at full utilization, the amortized solar panel cost of solar electricity is $50/(10x365) = $0.014/kWh when amortized over 10 years!!! 

  Back in 2019 (five years ago), I co-wrote an article that forecast that cooking electricity in rural Africa could drop below $0.02/kWh by 2030.  And it looks like we were right! In fact, it looks like we beat the 2030 target!!  See:


  I remember thinking when I wrote the article: "Hope this doesn't ruin my academic reputation ... it makes me sound like a crazy, starry-eyed optimist." Crazy thing is, that the article appears to have forecasted things decently well.

(5) New Cost-effectiveness Analyses

  FYI: there is a philanthropic movement called "Effective Altruism" (EA) that tries to use "evidence and reason to figure out how to benefit others as much as possible, and taking action on that basis."

  For anyone who has been reading my friends and family letters for a while, you will know why such a movement appeals to me. I have also been going to EA conferences for a little over a year now.  And while the movement is pretty nice, it still has its gatekeepers and thought "leaders" so that an outsider like me is still pretty much an outsider.  But at least there are a lot of folks in the EA movement who like the quantitative approach that I take to maximizing impact for development projects in rural Malawi. 

  During a conference last year, I got in contact with an organizer with the UC Berkeley EA student group.  I organized a batch of student projects for them during Spring '23 semester, and organized another batch of student projects for Fall '23.  You can see the projects for Fall '23 described at:


  You will notice that this most recent set of projects, I tried to get the students to do cost-effectiveness analyses for our various solar interventions in Malawi.  I also asked them to post their results in the online discussion board of the EA movement which is called the "EA forum."  About half of the groups were able to make enough progress to post something. You can see their posts at:


  Most notable perhaps was how using small solar cars saves lives.  Specifically for less than $5000 of donated support, this intervention will typically save at least one life.  So that is the cost of saving a life in rural Malawi: less than $5k. For details, see:


  I think this result is quite interesting: if you want to introduce solar cars to rural Africa, probably the best way to do it is to put them in service of transporting people to health clinics and hospitals.  This way, the lives that are saved with the transportation service justifies the near-term subsidy that the small solar vehicles need to be sustained in a place like rural Malawi. 

(6) Internships and Next Summer's Work

  Our new non-profit sponsor (Omprakash) has the mission of "building mutually beneficial & educational relationships between grassroots social impact organizations and volunteers, donors & classrooms around the world."  By joining Omprakash, we become one of their "partners" and they have offered to recruit volunteers and interns to work with us in Malawi.

  In order to fit in with the Omprakash program, we have therefore created seven "social impact internships" for folks who want to volunteer and work with us next summer. These are:

   1) Impact evaluator: Solar pumps

   2) Promoter: Solar electric cooking

   3) Organizer: Solar cars for health

   4) Data collector: Forever batteries

   5) Field evaluator: Forever lights

   6) Trainer: Digital payments for collectives; and

   7) Tester: Cooking fuel use

  This perhaps gives you a pretty good idea of all of the activities and developments that we hope to get organized next summer.  If you know any volunteers who are willing and able to help, please send them our way!

People can apply at:


And you click on the box that says "View Our Current Positions" to see the details of the volunteer work that would be most useful

That's It for Now

  Well that's it for now. I personally have three more trips to Malawi that I have to take this year.  One trip starts in a week, where I help organize cooker activities.  Another trip in April/May is dedicated to working on Forever Batteries. And the trip for June to September is for everything else.

  I am hoping that by September, everything is organized well enough so that in 2025, I only have to spend a month or so in Malawi to help keep things moving.  Fingers crossed!

In love and struggle,

Robert VB