Firstly, I have been frantically finishing work on a solar refrigerator. There was more work to be done than I anticipated (seems to be a common theme!). I also worked hard toward a solution that in the end did not work out. Essentially, to provide thermal mass to the fridge I wanted to seal a large amount of water inside. Turns out making something water tight is easier said than done. In the end I had to give up using water and instead turn to using concrete. The thermal mass is about half that of water, but still should keep the fridge cold for several hours during a power outage.

And so I traveled north to Rwanguba empty-handed. However, while there I did get some great work done. A few years ago the hospital had a small solar lighting system installed by the International Rescue Committee. Last time I visited in July it was not functioning, and probably hadn't been in a while. This visit I was determined to offer something, even if not what I had originally hoped for. And so, after a few hours work with the staff engineer, we got the lights back on. With lighting now for two wards, they will be able to run their generator much less, saving money.

And so now I have to take stock of the next steps. The fridge is still being tested - it's now dropped 6 degrees C in 2.5 days, so I think maybe, just maybe, it's working. Apparently it takes a long time to cool concrete! The benefit though is that with high thermal mass, it will also take a long time to warm up, providing cooling even during power outages. Looks like my calculations were incorrect!
So much of this work is new for me, I have been learning a lot. The principle lesson is that success is quite unlikely the first time you try something. I'm trying to not be discouraged by failure, but to learn what went wrong and try again. I think we've all heard this before, but it's quite different to be told that than to actually have to go through it.
Oh my goodness, this mzungu actually has a comment that may be of actual value! Are we installing some insulation on the exterior of the concrete? Depending on the design temp of the fridge and where it is being place (in the ground, I wonder?), it may make sense if it is an option. God be with you!
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