Advise on power saving products

I'm currently considering implementing energy or power saving products to cut down on my electricy bills.

I have 7 freezers. There are two companies that had approached me, with both utilizing different technology.

As I really know nuts about electrical engineering, I would appreciate it if someone can help me on this matter.

One of the companies that approached me produces their products locally. They created this technology called 'CAP BANK' and the product is attached to the main board. Whatever power is needed is clamped & absorbed by this cap bank and then distributed to the respected machinery (freezer motor, stand alone refrigerator etc). The units are attached to the MAIN BOARD.

Apparently it can save a minimum of 15% off my bills, besides prolonging machineries life span.

The second company is a MNC. Their products are named SAVA WATT, which I believed is from the UK. Apparently, they utilise the solid state technology. Their units are attached to the motors.

They also mentioned that it can save me 15% plus equipment maintenance etc.

Going by price & ROI, the former would be the obvious choice. It is just that I would know which one is more reliable.

Anyone can help?