The power company isn't the one who fucks you over..
Think of it like this.. Gas companies.. Each winter EVERYONE who uses GAS heating, their bill goes up. The gas company doesn't care, and it's not a red flag. They are happy you are using more, and paying for it.
Electric companies - THEY COULD CARE LESS. If you are using their power, at any amount. If you AREN'T stealing it, and are paying for it, they are happy.
BUT - IF the police get word of anything that's going on at your place, they can and WILL goto the power company to view your meter usage. ANYONE can do this, there is NO warrant needed.
Before I moved into my new house, I went to the electric company, and asked what the current monthly bill was at the residence I was moving into. They showed me EVERYTHING. When it went up, down, and the dollar amount of the bill.
In the summer people have central air, Air conditioners, pool heaters, pool filters, a LOT of other power consuming appliances.
As long as no one gets a RED FLAG that your growing weed, your power consumption should not be a concern. Pay for it, don't steal it or try to 'cheat' the system.
PS, the average toaster oven is 1200WATTS+ , just to put it into perspective.