Reply #48: Greenhouse operations [View All]

[Filius Nullius]

You are so right about avoiding heat loss. Continuous 24-hour-per-day operation is guaranteed by placing tight water-filled black tubes on the floor of the greenhouse. The tubes heats up during the daytime and radiate heat at night. These tubes only need to be filled once. See the following page http://www.sbp.de/de/html/projects/solar/aufwind/pages_auf/principl.htm.

The large glassed-in collection area at the base will be nearly perfect for greenhouse gardening and hydroponics. The water needs of the growing biomass can be at least partially supplied through the collection and recycling of water that will condense out of the hot air when it cools and passes over metal fins near the top of the tower. Actually, because of the higher humidity in the southeastern U.S., Solar Towers located there might have an advantage as far as the collection of water for agriculture is concerned.

I have no idea about the proportion of solar energy that will be absorbed by the plant life and how much will remain to drive the turbines. However, I have never heard of it being a problem. During the day, the plants will photosynthesize and produce oxygen as a byproduct. If large numbers of Solar Towers are constructed, this may actually be some help in reducing the amount of greenhouse gases in the atmosphere. Since the plants will mainly respire warm CO2 at night, that will reduce the net oxygen production somewhat, but it may also enhance the ability of the turbines to produce electricity in the evening.

The cultivation of algae is an interesting idea. I do not know if anyone has pursued it yet.