The federal income tax standard deduction is used in lieu of itemized deductions, so it is not possible to claim any deductions for fuel-efficient car purchases and the standard deduction. However, there are several federal tax credits for electric and hybrid vehicles that can be claimed with the standard deduction.
The federal government offers tax credits of up to $7,500 for purchasers of qualified electric or plug-in hybrid vehicles as of 2015. Rather than acting as a deduction from taxable income, these credits directly reduce the tax liability of the purchaser. For example, a person who had a $10,000 federal income tax liability and purchased a vehicle qualifying for the full credit would only owe $2,500 in income taxes after the credit.