PROJECTING CROP GROWTH IN A FLUID-ROOF SOLAR GREENHOUSE

A fluid-roof solar greenhouse admits only the photosynthetically active part of the solar radiation and excludes the remainder, storing it for night-time use.
The energetics of such a device have been analyzed earlier by dynamic simulation.
Crop growth conditions in the daytime in a fluid-roof solar greenhouse are typified by lower leaf temperatures and by decreased transpiration and water stress, in comparison with standard greenhouses.
Accordingly, more favorable conditions for photosynthesis and dry matter accumulation are maintained for longer periods of time.
An attempt at quantification of these effects is reported.

The principal results of our calculations are that in the subtropical climate of South-Central Texas, during the cool season, productivity in a fluid-roof greenhouse is slightly less than that in a standard glasshouse.
However, the efficiency of CO₂ enrichment is more than twice as high.
In contrast, in the summer, the fluid-roof design results in a much higher production than in a glasshouse, particularly with CO₂ enrichment.

Symposium on Potential Productivity in Protected Cultivation

C. H.M. van Bavel

https://doi.org/10.17660/ActaHortic.1978.87.32