supplemental heat--it's working

Today is January 6.  We started using the milk house heater at night on New Year's Day.  Today, like the past couple mornings it is above freezing despite overnight temperatures outdoors in the single digits or near zero.  Today at daybreak:

The little seedlings aren't showing growth yet but I have hope.  BSH (before supplemental heat) our electronic thermometer which reads the current temp but records the highest and lowest temperatures attained during the 24 hour period would almost always read LL overnight.  The potting mix in the planters would be frozen and there would be a layer of ice in the blue barrels on the surface and sometimes around the inside perimeter.  I do not know for sure at what point the thermometer switches from reading numbers to reading LL but I do know that there have been some number readings in the mid 20s.  Since adding the milk house heater the water in the blue barrels has had no ice form overnight.  Once the current ice melted it has not reformed and there has not been any LL readings recorded overnight. 

Other factors  that must be taken into consideration is that November and December are traditionally less sunny.  In fact, according to the weather calendar on Weather dot com for our zip code December had only one sunny day and less than half of the month was even partly sunny.  There were also nine days where the low was single or double digits below zero.  So far we haven't had a -15 to really test our heater.  January shows a couple of 0 readings but the -12 on New Year's Day was it 1 a.m. (BSH)!

We are also working to fine tune the managing of our heat sink but that deserves it's own post...