Whether you can take a tax credit for a plug-in electric vehicle (EV) depends on the manufacturer. The tax law set a 200,000 sales limit on manufacturers for these vehicles and Tesla and GM have already passed this limit; no credit for the purchase of a Tesla or GM EV is currently allowed. For other plug-in electric vehicles, the amount of the credit varies with the model. The IRS has a list of qualifying vehicles.
Writing off the cost of depreciable property over a period of years, usually its class life or recovery period specified in the tax law.