Data Log for the Roper Solar Greenhouse
215 Maywood Street, Blacksburg, Virginia
December 2009

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Monthly weather data

It is desirable to compare the YSGH operation temperature data to the external temperature data. Since there is not a mini-weather-station at the YSGH, the daily high and low temperature data taken at the Blacksburg VA National Weather Service Office are used for comparison. The distance between the weather station and the YSGH is about four miles.

Air temperature, humidity, light intensity and CO2 concentration behind the center post

The green-data axis is on the right with the blue data.

Notice that someone turned the heat-sink fan off on 13 December and it was off all night.

Blacksburg VA temperatures, Wind & Sunshine

The black curve is the temperature at the center post in RSGH; the other curves are temperatures at the Blacksburg weather station.

The units for wind & sunshine are arbitrary. Sunshine really means cloud cover in tenths of the sky.

Heat Sink Energy

The daily cycle of energy being stored in and taken out of the heat sink is obvious. This calculation is not very accurate because the temperatures at the inlet and outet at the two ends of the RSGH may differ even when the heat-sink fan is not on. (The energy calculation involves temperature and relative humidity at the heat-sink outlet and inlet.) The high negative correlation between high temperatures and negative "energy out-in" is obvious.

Soil Temperature

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Plants pictures

Comparison of the four quadrants:

Roper plot:

Roper Plot
  • West row on right: Burpee Gourmet Blend lettuce (Planted 11 Nov 2009)
  • Middle Row: Chinese Rose White radish (Planted 11 Nov 2009)
  • East row on left: Burpee Classic Mix Mesclun (Planted 11 Nov 2009)
  • Row between east and middle row: Chinese Rose White radish (Planted 25 Nov 2009)

Second Roper Plot

  • Short row on right next to tank: Spinach
  • Next row: Spinach
  • Next row: Broccoli

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L. David Roper,;