winter temps and a solar kiln

[Tom L]

just wondering how hot your solar kiln gets in the winter months .

say a day with full sunshine, 20 degrees F outside temp.

what kind of temps do you see on the inside?

[GeneWengert-WoodDoc]

The VTkiln gets about 30 to 40 F above outside at about noon to one o'clock with the fans on and no wet wood inside.  However, if there is water inside that is frozen, a lot of energy is needed to melt the ice, so it will be cooler.  Also, the sun angle is low in the wintertime, so the peak temperature does not last very long.  The hotter kiln will be one that has good insulation and two or three layers of clear solar covers.

With wet wood, much of the heat is used to heat the wood and water and evaporate the water, so temperatures are much lower.  Plus with wet wood, the vents will be open so that some heat is lost to outside when venting, but the fresh air brought in is lower in humidity, so that helps drying.

[Tom L]

thanks for the reply Gene

I was hoping to funnel some of the heat into the basement during the winter months , but that seems a little cold for what I was hoping for.

[Bill Gaiche]

I checked mine today. Lumber M/C was 10%. Outside temp was 55 deg and kiln temp was 125 deg. bg

[GeneWengert-WoodDoc]

Bill's temperature increases are typical for a kiln with dry or no lumber in it...the solar heat is used for heating and not evaporating.  If the fans are not running, then the heat will naturally go to the top of the kiln...it will be really hot in the top of the roof.