PPFD and kWh conversion

About microscopic forms of life, including Bacteria, Archea, protozoans, algae and fungi. Topics relating to viruses, viroids and prions also belong here.

Moderators: Leonid, amiradm, BioTeam

Post Reply
Posts: 1
Joined: Thu Mar 16, 2017 7:29 pm

PPFD and kWh conversion

Post by agoff3 » Thu Mar 16, 2017 7:33 pm

Hi, I am having some problems trying to understand light conversion.
I am trying to work out what 25 umol m-2 s-1 would be in kwh and I am using a cyanobacteria that grows at 470nm.

How do I approach this? From what I understand, one unit is measuring brightness and the other energy, and I can't figure out how to get from one to the other?
If anyone has any resources they could point me to, id be really grateful. Thank you

User avatar
Posts: 23
Joined: Mon Aug 14, 2017 11:59 am

Re: PPFD and kWh conversion

Post by Vmedvil » Mon Aug 14, 2017 3:08 pm

Well, you are going to need to use the physics equation E=h*C/ λ to convert the light wavelength to energy per photon, first convert nano-meters into meters then plug this into the equation modified for wavelength.

E= Energy in (joules per photon)
C = Speed of Light in (meters per second)
h = Plank's constant
λ = wavelength in meters



Next, Remember that photons hit one atom or Atoms per photon a physics concept called the photoelectric effect. so, take the Energy per photon times how many moles you have or ΣE = E * (Atoms) , Always remember to convert your micro-moles into Atoms.

E = Energy per Photon (Joules per photon)
Atoms = How many atoms are being hit by photons in (Atoms * Photons)
ΣE = Sum of Energy of all photons hitting your atoms in (Joules)


Lastly, you can convert the joules into another unit of energy being kilowatt hours
Einstein would turn over in his grave. Not only does God play dice, the dice are loaded.
-26 Dimensional Quadratic Super String Theory

Post Reply

Who is online

Users browsing this forum: No registered users and 2 guests