Electronic Ballast-saves Energy in 3 ways.

High frequency Electronic Ballast enable a fluorescent lamp to generate same amount of light using less energy due to rapid ionistion this alone results in 10% to 15% power saving

Lamp fixture using high frequency ballast operate cooler and allows lamps to operate more effeciently. Saving 5% to 10% accrue from less need to air conditioning

Use of electonic ballast themselves saves approx.40% power than their conventional core & coil part

Thus total saving by Electronic ballast could be in excess of 60% or more and use of energy efficient Lamps such as compact fluorescent light(CFL) can result in power saving upto 85%!

Electronic ballast for 4 feet 40 W / 36 W tubes. Feature:
40% power saving
0.98 power factor
Instant start, No need for Starter
Low voltage operation upto 90 volts
EMI & RFI suppressed, hence no interference to computer / TV etc.
FIRE proof metal body
Size matches that of conventional choke for fitting
Low heat generation 
Significantly increase tube life
State-of-the art technology to meet harsh indian conditions
Transient voltage protected
Weight: 180 grams

Applictions:
Commercial Establishment, Industries, Apartments, Schools, Offices, Hospital.