Regeneration using Solar Powered Hydroponics J. Bradley Morris and Ken Manley

Ken Manley, Technician, Special-Purpose Legumes, New, and Miscellaneous Crops

History of Hydropon ics Use of complete nutrient solution in U.S. (1925) – 1935 – New Jersey Ag. Exper. Sta. improved sand culture method. – Water and sand culture methods used at Calif. Ag. Exper. Sta. – Limitations solved by adding sub-irrigation systems at New Jersey and Indiana Ag. Exper. Sta. Post W.W. II years – interest in the SW U.S. in gravel culture of tomatoes and cucumbers but systems not perfected and abandoned. After about 20 yrs. Plastic use in hydroponics for lining growing beds instead of using concrete. Interest decreased again.

1925 – 1935 continued Another 20 yrs. passed since real interest in hydroponics occurred once more for regions prone to groundwater pollution with nutrient wastes or soil sterilants. Ref. University of arizona.

History of Solar Power 7th Century B.C. - magnifying glass – first solar collector (Swiss scientist – Harace de Saussure). 1800’s: – Photovoltaic effect discovered (French scientist, Edmond Becquerel). – Solar powered engines and predecessor of modern parabolic dish collectors (French mathematician, August Mouchetr). – Description of first solar cells made from selenium wafers (American inventor, Charles Fritts.

1900’s – Solar collector invented (William Bailley, 1908). – Photoelectric effect explained (Albert Einstein, 1921). – First photovoltaic cell (PV) developed in U.S. (Bell Labs, 1954). – First commercial office building using solar water heating (Frank Briders, mid-1950’s). – Hoffman Electronics achieves 14% efficient PV cells (1960). – NASA launches satellite powered by PV array (1964). – Less costly solar cell designed (Exxon Corp., 1970). – First PV research and development (U. of Delaware, 1972).

1900’s continued – U.S. DOE launches federal facility dedicated to solar energy (1977). – Development of a PV solar cell that converts 32.3% of sunlight into electricity (Spectrolab, Inc. and NREL, 1999). 2000’s – Solar panels on solar power array deployed in space (2000). – And continues. Ref. U.S. DOE, Energy efficiency and renewable energy, the history of solar

Objectives Hydroponics – Can it be a useful tool to regenerate difficult accessions? For example - unadapted, poor seed producers in field or greenhouse, endangered sp. Solar power – Can it be used with hydroponics outdoors or in a cold frame? – Can it save energy costs?

Two 12 V deep cycle batteries with charge controller. Outlet cord connecting solar panels with batteries. 4 high wattage solar panels (15 watts each). Liquid nutrient-filled container with 12 v pump and filter.

Winged bean, PI in hydroponics Grodan – water absorbent stonewool. Made from molten rock spun into fibers, compressed in to cubes, blocks, or slabs. They are sterile, structure is maintained, absorbs water. Hydroton – pelletized clay, inert, pH neutral, drains freely, no excess water, good oxygen levels.

Liquid nutrients used in hydroponics for winged bean, PI (m) Ca 5% Co % Fe 0.1% Mn 0.05% Mo % (g) Mn 0.5% (b) Mg 1.5% S 1%

Liquid nutrient applications ¼ tsp/gal of m, g, and b tsp/gal of m, g, and b to tsp/gal of m 3 tsp/gal of g 1 tsp/gal of b to tsp/gal of m, g, and b to Present pH = 6.0

Winged bean, PI production in hydroponic system over time Approximately 2 month, º F Night/day

Costs for hydroponic and solar panel system used 2, 12 V, deep cell $ ea = $ battery $5.00 ea =$ ring terminals for $3.49 ea =$ battery $11.49 ea =$ , 15 Watt solar ea =$ Mounting $89.99 =$ Hydroponics $ =$ V pump for $34.95 =$ Nutrients and hydroponic =$ pH control kit =$ $ =$ Total$1,970.01

Advantages

CastorbeanHibiscus spp. -$1,970.01/hydroponic/solar system -Estimated electrical cost for hydroponic/solar power system in the grhs. ($97.00/yr.). -Cost effective.

Disadvantages - Inclement weather producing hail stones, very high wind, or mowing near causing rocks to damage solar panels. -Batteries require replacement/2yrs.

Conclusion -Hydroponics is a useful tool for regenerating poor seed producers under normal growing conditions. -Hydroponics can be used in curation research. For example – study root zones easily, nutrient uptake, root structures for drought tolerance, allelopathy, and root phytochemicals.

-Yes, it can be used to power a hydroponic system outdoors.