Dear Ali D. Salman ,

the amount of heat Qi produced by an individual lamp i is equal to the electrical power Pi*) picked up by this lamp times the operating time ('switch on' time) ti:

Qi = Pi * ti

This amount of heat is irrespective on the type of the lamp.

The energy of all typs of radiation will end up in heat...

The total amount heat Q produced by all the lamps will be the sum over all Qi:

Q = sum(Qi)

Best regards

G.M.

*) the nominal electrical power (normally in W) is given in the data sheet of the lamp and is as well printed onto the lamp housing

Dear Mr.Gerhard Martens

thank you very much for your attention

I recommended your logically answer,

but my question about the cooling load factor for the lead lighting

also you know sir LED lighting feeding with DC voltage and that mean there is a an electrical transformer with heat despeciation from electronic part

so I repeat my question about the effects of the source above to the real amount of total heat released from the LED lighting and its CLF value to the cooling load estimation to the building

with my respect

Dear Ali D. Salman ,

thanks for feed back.

To my opinion the specification of the power of any lamp (LED, incandescent, halogen, neon or CFL) is equal to all the amount of the electrical power picked up by the lamp and is not only restricted to the radiative/optical part.

This power converts into

a) radiative energy (here the visible light of the LED), which is at the end converted into heat,

b) the heat in the LED chip during operation, which has to be removed by a heat sink, in order to limit the semiconductor temperature, and

c) any heat produced by the electronics (and transformers) in the lamp housing which is driving the LED.

At the end all electrical energy (specified by the manufacturer) is converted into heat.

If in the case of a special design a separated power supply is used outside the lamp housing, you have to add the heat dissipation of that power supply/supplies. But the manufacturer should know how much energy is dissipated in heat here.

Best regards

G.M.