Roommate Is Claiming I Owe Him Money Because My "expensive Cooking" Is Making The Electric Bill Higher. Can He Actually Make Me Pay Extra? (ca)

Location: California, USA

This is probably the weirdest legal question I'll ever ask but here we are. Been saving up for months to buy a decent stand mixer because I'm really into baking and my old hand mixer finally died. Dropped about $350 on a KitchenAid (worth every penny tbh) and have been using it maybe 3-4 times a week to make bread, cookies, whatever.

My roommate has suddenly decided that my baking hobby is "driving up the electric bill" and wants me to pay an extra $40 a month on top of our normal 50/50 split. His logic is that my mixer uses more electricity than his gaming setup (doubt) and that I'm being "financially irresponsible" with my baking. For context, our lease says we split utilities equally and doesn't mention anything about individual usage. The electric bill has gone up maybe $12 total since I got the mixer, and that's probably more from summer heat than my 20 minutes of baking every few days.

He's now threatening to "take legal action" if I don't agree to his new payment plan. He also mentioned something about small claims court which honestly made me laugh because we're talking about like $5 worth of electricity here. Can he actually force me to pay extra utilities based on which appliances I use? Is there any legal ground for him to stand on here or is this just roommate drama? Our lease is pretty standard and doesn't break down utility usage by specific devices or anything.

Really don't want to lawyer up over a stand mixer but this dude is being absolutely unhinged about it ????