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What I am building is known as a Photobioreactor. It is known that factors contributing to efficiency in such a reactor are, a short light path, and turbulence. A short light path can be achieved with a wide flat light source such as the one used in the test, high turbulence can be achieved with bubbles. It is also important to have low hydrodynamic stress, so the cells are not damaged, so the bubbles are used for their pumping action also. You cant just run an algae cuture through aly old pump, it would become damaged. The final configuration of a production level reactor would have to be similar.

In addition I have built a calorimeter cell for measuring the efficiency of the light source. It consists of 1 1/2 inch styrofoam constructed into a shallow pan and lined with aluminum foil. This then covered with a double pane of glass and airtight (nearly). The Idea is to use a mass-flow approach to measure the heat of the air going into the calorimeter and compare that to the heat of the air coming out. The waste heat from the light can be measured as the light radiates out of the cell through the glass. The energy efficiency of the cell can than be calculated. I've been learning about ecology and bidchemistry from scratch and its taking some time to figure out what to do. Are there any ecologists or biochemists out there? I could use some help.


I have no problem with what you say, however It looks like we are taking about two different things. The over all intensity of light getting through the biomass would not be used to tweak the process. The acceleration of the decrease in transmitted light intensity (amount of change) could be used to tweak the process, and would indicate more rapid growth. This all would not be linear, but so what, it is still a indicator. This is all depending on how you have constructed your test unit. I am assuming a steady state production unit, light going in - biomass coming out in constant flow. If you have a steady state condition and you add more nutrients and the transmitted light goes rapidly down then it needed the nutrients. If the transmitted light goes up then it slowed the growth process down.