How long does it take to heat up and cook? James Wolf August 30, 2015 18:27 Follow Have more questions? Submit a request Comments Fanie June 25, 2015 13:31 There is a solution for overcast days where heating is limited. We cook our foods when there is good sun, then dry it for use in overcast days when you have less heat, just enough to heat it up after re-hydration. Dried food can last many years. To use the Gosun for drying cooked foods you will need a small fan and a small solar panel to power it, to blow air in under the trey, circulate hot air over or through (better) the food and out again. This may be something Gosun will consider as an add-on alternative. I tried this with a normal geyser glass tube and it worked well... the geyser tube is very long and small diameter, difficult to use. Cooked rice dried out in less than a day of good winter sun, I regulated the temperature with a towel to around 60oC. Dried food weigh a lot less and most package a lot smaller which makes it easier to transport. Most uncooked dried foods are tasteless, takes mostly hours to re-hydrate and needs to cook for a long time (hours), so we cook ours and then use it.