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SolarAid’s Impact Calculator: What Impact Will My Donation Make?

MFG Archive, Profiles

In our latest profile, Richard Turner from SolarAid talks about how their new impact calculator uses data to show their donors where their contributions are going.



We are very excited at SolarAid at the creation of an impact calculator on our website where donors can type in the amount they wish to give and our calculator provides the impact it will have. Give it a go yourself here.


Most fundraising uses activities or items from a budget line as marketing proposition. Your donation ‘could’ fund this activity or item. The activities used in the marketing are in effect examples of what your donation might fund – as they represent one of many activities.


An output however is often the sum total of activities. And impacts are the consequence of your output. Sometimes the impacts are not so obvious. When visiting a water project in Ethiopia I where the outputs led to more water points nearer to the community, one of the impacts was more girls attending school, because when they had to collect water at a long distance they started to drop out of school. Of course your activities may have a negative impact too. This is the real importance of measuring impact.


Are you doing the right thing?


So when SolarAid started its programme selling solar lights at a fair market price in Africa we also set up a research team to evaluate its impact. The purpose was to determine whether we were doing the right thing in order to achieve our goal of eradicating the kerosene lamp from Africa by 2020.


What struck me at the time was since our focus was on distributing and selling solar lights we had a clear output – the number of solar lights sold. So we devised a fundraising proposition on that basis. For every £6/$10 donated we were managing to sell a solar light at a fair market price in Africa. That’s simple inputs and outputs. You give £60/$100 we were able to sell ten more solar lights. This was the net cost of our operation, from fundraising through to implementation on the ground. $100 led to ten lights out.

“Using this data they were able to say what the impact of a solar light was. Some of the findings surprised us.”

Meanwhile the research team was collecting data on the impact of solar lights. Over the last few years it has assembled over 30,000 interactions with families who buy solar lights and agents who sell them. It’s been acknowledged as some of the best data on off grid communities in Africa (people with no access to grid electricity). Using this data they were able to say what the impact of a solar light was. Some of the findings surprised us. For example, each solar light led to at least one hours extra study and in some countries this was more. Families also made savings on average of $70 from no longer buying kerosene. And each solar light displaced the use of a kerosene lamp averting 200kg of CO2 a year.


And so the Impact Calculator was born. Initially it was an excel spreadsheet set up by the research team where we could type in the number of solar lights distributed and from that determine their impact in study hours, money saved and CO2 averted over a three year period (three years is a prudent estimate for the lifetime of a solar light). For study hours that’s 1,200 extra hours from the impact just one solar light.


We had successfully equated outputs, the selling of solar lights, to impact. And we had already determine the cost of our outputs. So now we could state the impact of a donation. At this point our programme distributing solar lights had scaled and now, instead of $10/£6, for every $5/£3 we received we were able to sell a solar light at a fair market price (our output).


Last year we put the impact calculator online. Donors can now simply type in their potential gift and see what impact it will have. During a UK Aid Match appeal with all donations doubled by the UK government following the suggestion of a supporter we added a column showing the double impact of a donation! Recently the impact calculator got featured in the Guardian as one of “the most innovative examples” of communicating social impact.


“It’s entertaining to use and easy to understand … SolarAid have recognised that they can raise money by using existing donors as real advocates for their cause.”


We also use the impact calculator to feedback to donors after they have given – pointing out the consequence of their support in study hours gained, money saved and CO2 averted. And now we have been using impact propositions in our campaigns.





I think it’s more transparent than using activities commonly in fundraising. Unlike activities impact is the ultimate consequence of a donors support and represents the sum total of all our activities. It’s taken some work but it’s worth it as it really does answer that age old question: what difference will my donation make?

Many thanks to Richard Turner for his piece on SolarAid’s new Impact Calculator. To find out more about the great work SolarAid do, be sure to follow them on Twitter at @SolarAid, and you can follow Richard at @ifundraiser.

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