earth tubes vs climate battery for a greenhouse

I've been designing a greenhouse, and being a 7a climate I need a way to keep things warm in the winter. This is mountain area, up around 8,000 feet.

I've been reading up on climate batteries (http://www.ecosystems-design.com/climate-batteries.html), and those look pretty cool. However, this guy uses simple earthtubes and has for 25 years (   https://www.youtube.com/watch?v=ZD_3_gsgsnk)    . Looks like no recirculation, just classic earthtubes. Bringing in subterranean temperature air (45F-50F).

Just curious what the advantages are of a climate battery, since it seems like you can use simpler earth tubes.

In the video at 2:30, he mentions that he has blowers circulating the air. In reality they are goth using the same concept.
1) Send hot moist air to the soil to store the heat and moisture
2) When it is cold extract/blow up the heat, and the moisture trans-evaporate up to into the air.
3) Repeat the whole, equaling the day and night temperature as much as possible.
4a) The system can be optimized, by increasing the amount of energy entering aka long skiny southern exposure
4b) Minimize heat loss with insulated northern wall (thick/low density/low thermal conductivity), etc
5) In the video he mentions that he goes down 8-12ft+ and stores the summer heat their for use in the winter, so we are no longer just talking about 24hr cycles but 12-36month cycles