This is a nice promise, but one's skepticism is inevitably roused by the information -- and lack of it -- available from the company's web site. The site is full of testimonials, accounts of how Tesla solved the world's energy problems but was prevented from gifting humanity with this achievement, promises of freedom from the grasping power companies, and warnings that the opportunity may disappear due to the hostility of those same companies.
What is lacking is any serious technical account of how the power is produced. It amounts to a sales pitch with no clear indication of just how the product's features lead to the claimed benefits. One must pay a sum of money before one can find out exactly what it is one is buying.
While it's impossible to deny the Vile Motives of Wicked Capitalism, especially in this day and age, neither should one overestimate the ability of the power companies to suppress truly revolutionary information in the context of the Internet.
If there really were a way to use a few hundred dollars' worth of easily-acquired hardware to generate unlimited free electric power, someone would be making it available to the world, and would not be charging money for the information. The fact that the principles underlying Energy by Tesla are not available except for a price -- not the designs, please understand, but merely the scientific principles behind the designs -- raises a red flag.