Understanding Light Energy for Plant Growth

Are your plants receiving enough photosynthetic energy?

If you use a light meter to measure foot-candles then you got it all wrong - at least that's what NASA says!

Do yourself and your plants a favor - BUY Your Quantum Meter Today!

Aeroponic High Capacity Unit & Light Array
Contents

Product Info



Plant Development is dependent on the specific spectrums of the light source and the usable light energy

Only 37% of the energy in sunlight is within the wavelength (colors) useful for photosynthesis, while 62.4% is infrared (thermal energy) and the remaining 0.6% is ultraviolet. Photosynthesis in the plant leaf is powered by 1% of the sunlight that falls on the plant, 10% of the sunlight is reflected and 10% passes through the leaf. The leaf will retain 80% which is used for transpiration. Some of the light is re-radiated, while the fraction that remains is used for building food from the carbon dioxide, minerals and water.1
 

Percent of usable 
light energy

Light Spectrum Range
Percentage of usable of light energy (0-100% y-axis)  / Light spectrum range (x-axis). For photosynthesis the most important spectrums of the light are blue and red.1   Germination, flowering and stem growth are influenced by red to far red. Fluorescent bulb.

In artificial environments it is important to keep these factor in mind when programming the light source for the plants life cycle.  According to our research for NASA, care should be taken to ensure that the plants grow under an artificial light source have adequate infra-red protection to prevent undue environmental stress for the plants. For the associated light spectrum consult your bulb's manufacturer (see below for some comparisons).

1. The Solar Greenhouse Book
2. A Gravity-insensitive High-performance Aeroponic System for Food Production in Space (1997 NASA SBIR Phase I Report - Aeroponics International)



Usable Light Energy of Artificial Lighting compared to Sunlight

Useable light energy for plant growth is measured in Micro-Einsteinís ( micro-mols of photons per meter squared per second). The sunlight reaching our plant is approximately 2,200 micro-Einsteinís on a cloud-less day  and 170  micro-Einsteinís on a very cloudy day.

For indoor growing under artificial lighting a range of  200 to 500 micro-Einsteins is considered by experts at NASA to be minimal energy level for plant growth.

The higher the bulb wattage the further away the plant must be from the light source to prevent environmental heat stress that can cause the plant to transpire too quickly. Excessive transpiring can dehydrate plants leading to wilting and poor growth. Likewise, the further the plant is from the light source the less available useable energy is delivered to the plant.  The indoor grower most tune light energy resources as well as other environmental variables for optimal growing conditions.
 
 
Indoor growing requires a careful consideration of the artifical light for photosynthesis

 

Criteria for maximizing the artificial light energy for photosynthesis

The indoor grower has several options for maximizing the artificial light energy for photosynthesis, they are as follows:


Aeroponics International has developed a high efficiency Light System that meets the above criteria to deliver the optimum light energy level to your plants.



Chart for Micro-Einsteins per watt of various types of light bulbs

Below is a chart that can help you in determining the useable light 
energy for your plants. For optimum usable energy for photosynthesis, 
select a bulb that has the lowest wattage with the 
highest usable energy coefficient with less than 1.5°F temperature 
rise at 4 inches away from the light source. 


Can your artificial light source do this?

Measure Micro-Einsteins with our quantum meter
Full spectrun high-efficiency light array

Our LighArrays offers exceptional Micro-Einsteins out per watt (160 -240 watts)
Light Array: 160 watts Light Array: 240 watts  

More Light Array models - click here

Micro-Einstein Bulb Comparisons
 
BULB Type: 
Distance: 

Micro-Einsteins: 

Measured with a Quantum Meter

Usable Energy Coefficient (micro-einsteins per watt)
Incandescent


100 watt 

3 inches
310
3.100
Incandescent


100 watt 

6 inches
190
1.900
Incandescent


100 watt 

12 inches
65
0.650
Incandescent


100 watt 

18 inches
27
0.270
Incandescent


100 watt 

24 inches
18
0.180
Incandescent


100 watt 

36 inches
9
0.090
Aeroponic BenchTop Pro Unit
Low wattage, high efficiency light includes infrared & UV filter


20 watt 

3 inches
1279
63.950


20 watt 

6 inches
413
20.650


20 watt 

12 inches
145
7.250


20 watt 

18 inches
122
6.100


20 watt 

24 inches
65
3.250


20 watt 

36 inches
32
1.600
Sodium


250 watt

3 inches
250
1.000
Sodium


250 watt

6 inches
99
0.396
Sodium


250 watt

12 inches
30
0.120
Sodium


250 watt

18 inches
14
0.056
Sodium


250 watt

24 inches
10
0.040
Sodium


250 watt

36 inches
7
0.028
Gro-Lite


100 watt

3 inches
420
8.400
Gro-Lite


100 watt

6 inches
135
2.700
Gro-Lite


100 watt

12 inches
60
1.200
Gro-Lite


100 watt

18 inches
31
0.620
Gro-Lite


100 watt

24 inches
18
0.360
Gro-Lite


100 watt

36 inches
9
0.180
Fluorescent


40 watt

3 inches
52
1.300
Fluorescent


40 watt

6 inches
36
0.900
Fluorescent


40 watt

12 inches
13
0.325
Fluorescent


40 watt

18 inches
7
0.175
Fluorescent


40 watt

24 inches
5
0.125
Fluorescent


40 watt

36 inches
2.5
0.063

 

Product Info:



Also see:

How to maintain a sterile environment for plant growth

Understanding Light Energy for Aeroponic Plant Growth

Aeroponic BenchTop Units for indoor growing

General Overview of Aeroponics

Tomato crops produced using Aeroponics

Trees and Shrubs Database Successfully propagated using Aeroponics

System Layout

See the Component Descriptions of the above systems

Seed Germination Accessories

How Aeroponics works

Information on Aeroponic Growing

Biocontrol info:

            Biocontrol Brochure

            BEYOND All Natural Plant Amendmentô Brochure

           Testimony Letters

Purchase ODC / Beyond  Biocontrols and Aeroponic Units and Systems

 

YEA!®
Eco-Friendly
Aero vs. Hydro
Blog

 

Use natural biocontrol products visit www.biocontrols.com