ALPHA POWER SOLUTIONS Presented by Eric Solot An Introduction to Power Factor Correction.

ALPHA POWER SOLUTIONS

Presented by Eric Solot

An Introduction to

Power Factor Correction

What is Electrical Maximum Demand?

• Demand = Voltage (Volt) X Current (Amp)• Maximum Demand = highest average

demand in a 30 minute window, usually during a 30 day period

• Consumption (kWh) vs demand (kVA)• Why utility companies charge for

maximum demand?

What is Power Factor?

• Most loads in modern electrical distribution systems are inductive (require or generate a magnetic field):• Motors• Transformers• Lighting ballasts• Induction furnaces, etc

What is Power Factor?

• Inductive loads require 2 kinds of current:• For the working power (kW): to perform the

actual work of creating heat, light, motion, machine output, etc

• For reactive power (kvar) to sustain the magnetic field• Does not perform useful “work” but circulates

between the generator and the load• Results in higher loading on power sources as well

as the distribution system (electrical cabling and transformers)

Benefits of power factor correction

• Reduction in apparent power• Lower electricity bills• Increased system capacity• Reduced volt drop• Reduction in (heat) losses• Automatic capacitor banks allow for optimal

compensation during changing load cycles

Capacitor banks and cabinets

• Modular design• Indoor or outdoor application (IP rating)• Natural or forced ventilation• Corrosion and dust protection option

• Protection against capacitor pressure build-up:• Expansion zone in the aluminium

housing• Internal wire

• Gets severed when the housing expands• Acting as a back-up fuse

• Aluminium housing allows for optimal heat dissipation

Capacitors

• Consist of a thin plastic film on which a layer of Zinc and Aluminium has been sprayed

• This film is then tightly rolled up and placed inside an Aluminium housing

• Uncorrected power factor• Target power factor• Current and voltage harmonics present in

the system• Load changes• Unbalanced loads• Installation constraints

Factors influencing PFC investment payback

period

• Only applicable to industrial and commercial installations, usually not residential

• Accurate measurements of the electrical installation of a customer are required to determine the most cost effective solution

• Pay-back periods of well designed systems are usually shorter than 18 months and the equipment has a life expectancy of at least 10 years

Pay-back period for PFC equipment

• Power Factor Correction has up to recently not been a financially viable proposition for most companies – long pay-back periods due to low cost of energy

• Power factor correction still does not form part of IDM’s strategy:• not considered relevant contributor to energy

efficiency• ignore the potential reduction in heat losses

(which can contribute up to 3% of total kWh consumed)

Pay-back period for PFC equipment

Questions?