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Any suggestions for the possibility of using photovoltaic panels to supply energy for a machine?

A question from Catarina: We would like to explore the possibility of using photovoltaic panels to supply energy for a machine that is going to be implemented in Africa. We need to feed an electric compressor of 7,5 kW three phase 400V 50Hz for a small compressor plant during the daylight. This is for a remote area in Africa. What do you have for this application? Any Suggestions?

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This is a big ask for a photovoltaic system and raises some questions such as how many hours a day will the machine run and where in Africa will it be situated.?

To give you a rough idea of the power budget I have made the following assumptions:

Running time = 10hrs/day

Insolation = 6 hrs pk power/day

Running power of compressor 7kW (few machines run flat out at pk rated power all day)

Basic power needed = 10 x 7kW = 70 kWHr/day

To this you need to consider power losses in the inverter and cabling, say a factor of 1.25 = 87 kWHr/day

If the insolation is 6 hrs pk power/day your system needs to generate 87/6 = 14.5 kW

This is equivalent to 120 panels each with a capacity of 120W.

You'll also need to consider that the inverter needs to be capable ... (more)

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Hi Binaya,

In addition to all of the above considerations, which I agree with, you need to consider the daily stress, the regular maintenance, the spare parts, the "theft value" of all the parts, the security requirements, the availability and transportation (rainy season roads) in case you need parts. All the logistic issues that you will have to deal with.

But, on a more sensitive note, what are you trying to do with a 7,5 kW, 3 phase, 400 Volt compressor in the middle of Africa, if I may ask? Is there room for the task be re-engineered? Perhaps? I hope you do not mind me asking. 'nando

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2015-04-08 04:21:27 -0600
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Last updated:
Apr 15 '15