The Weather Inside an Earthship

Below are a few plots of temperature and humidity in our rental Earthship during our couple day stay.

 

This is only a couple days worth of temperature and humidity data, but still interesting.  It puzzles me why there is not more data out there on the thermal performance of Earthships.  It is easy and cheap to set up monitoring these days, and there are lots of Earthships in various climates  -- you would think there would be a lot of data available on how well they do. 
 

The only report I ran across is this interesting report on the thermal performance of an Earthship in Brighton:

http://www.lowcarbon.co.uk/files/earthship_case_study.pdf

While I suppose that fairly sunny weather in March is not to difficult a test for an Earthship, it did seem to perform pretty well.  The night outside temperature dropped to the low 20's, while the inside temperature remained in the 60's in the living areas away from the south windows.  The areas near the south windows got up to nearly 80F -- this actually felt fine.  

The inside humidity levels seemed very good for the dry climate around Taos. 

Overall, I would not have minded seeing the temperatures in the living areas that are deeper in the Earthship (ie away from the window wall) a few degrees warmer, but there may be some acquired skills to managing the climate in an Earthship that we were not familiar with that would have brought the temperatures up a bit.  That said, the temperatures were not uncomfortable, and are about the same as we maintain at home.

 

Here are the measured temperatures for our visit to the "Hut" Earthship in the Earthship Community near Taos, NM on 3/3/06 through 3/4/06.

 

 

Interior temperatures:

T Kitchen -- temp on top of kitchen table (btwn south windows and living room (same place humidity was recorded.

T Tree Low -- temperature at the banana tree near south windows -- perhaps 3 ft above floor.

T LvRm 2ft  -- temperature in the living room about half way back and about 2 ft above the floor

T Bedroom -- temperature  in bedroom on the bed headboard

T Floor  -- temperature on the floor in living room, sensor tucked under rug to get floor temperature.

T ambient -- outdoor temperature -- sensor in shaded area on north side.

 

The temperatures near the ceiling on the south side reached 100F, or maybe a bit more.  This was not a problem in that the high temperature was confined to the area above head level, and was easily controlled by opening the skylight in that is just north of the south windows.

 

Inside relative humidity and dew point temperature, along with interior temperature in the Kitchen area.

These seem like very nice humidity levels for such a dry climate -- presumably due to the "jungle".

I did not have a humidity logger for outside, but the reported humidity's at the Taos airport were:

Date          Time           Tamb        Tdewpt   Relative Humidity  I nside Calculated RH(1)

3/3/06        10pm         39F            19F                32%                    15%

3/4/06        4am           35                26                 43%

                    8am           23                21                88%

                    10am        39                26                48%                       20%

 

(1) This is what the interior RH would be if outside air were warmed up to the inside temperature without adding any moisture -- the implication is that the Earthship inside moisture sources are adding about 20% to 25% to the inside humidity level.

 

Outside light levels during the visit -- note that on the afternoon of the full day that the sun dropped off some at times.

 

Inside light levels during the day were in the 30 to 60 lum/sqft area -- which seemed on the dark side to me.

 

 

Gary

3/15/06