Solar Wood Kiln

Some time in 2015, I think it was, I built a solar kiln to dry lumber and firewood. I built the kiln to specs from a Virginia Tech design and have been using it to dry wood for the last 7+ years. It is mostly passive, with minor electric use to operate fans for air flow. It is starting to show its age now and I might need to replace the poly panels, but it has been great for getting lumber and firewood very dry.