The following are some links of products on the market. Let us know if you have any questions.
This website shows the power optimizer which uses frequency to stabilize the power.
It is device specific and also sensitive to power spikes.
poweroptimizer.com/index.htm
This website shows a typical KVAR unit which will increase you power factor but will not do anything about decreasing your kWh consumption.
power-save.com/3400.html
This video and guy tests the KVAR unit and shows how these units will increase your power factor (which in a residential application is not relevant) but does not decrease the power consumption.
youtube.com/watch?v=27XCJkKvPI4
