lemme see here... 1000 hp = 745.699871582 Kw for 8.2 seconds, that’s a hell of a lot more tan “nine cents” Assuming your hp conversion figure is correct, and with an average price of 10 cents/kw-hour:
745.7 kw x .10/kw-hr x 1 hour/3600 sec x 8.2 seconds = .1698538 dollars,
or about 17 cents.
They claim 350 HP on the current machine, which is 260KW - less the charging system losses and heat production. It's been too long since I've done the math but I think the input (in watts) is 1.707 times the expected energy output moment at full charge.
anyway... the $30K in batteries is enough to make you think twice...