I don't see how the numbers add up: this thing saves a nickel a KWH, max. A 100KW box costs $750K, according to the article. 24365$5.00 = 43800. So how does it

I don't see how the numbers add up: this thing saves a nickel a KWH, max. A 100KW box costs $750K, according to the article. 24365$5.00 = 43800. So how does it pay for itself in 3-5 years? Something is off, there. It's possible that TC fouled up - that the $750K price is for the 400KW unit that Google and Walmart are using, in which case the saving of $170K/yr would about work out.