My purpose is to save the energy consumption which is normally goes by reactive power.
I want to get the get the store of electrical to minimize the power consumption which normally goes up by the number of start-up of the compressor.

This installation of a capacitor will only reduce you electric bill if the power company that supplies your power charges you for kVAR-Hours in addition to kWh or if they cahrge you for "power factor". Find this out before you go and buy a capacitor.

If they do charge you for "power factor" or kVARh, then a capacitor will save you some money. You may want to ask the power company engineers what size capacitor you would need to buy to reduce your power factor.

Hope this helps,

Newton1Law