Technologies for Energy Security Act of 2017 This bill amends the Internal Revenue Code to extend and modify the tax credits for residential energy efficient property and investments in energy property. The bill modifies the tax credit for residential energy efficient property to extend through 2021 the credits for expenditures for fuel cell property, small wind energy property, and geothermal heat pump property. For each extended credit, the bill phases out the current credit rate of 30% of expenditures by reducing it to 26% or 22%, depending on the date that the property is placed in service. The bill extends the tax credit for investments in energy property for the following property with construction that begins before January 1, 2022: fiber-optic solar energy property, fuel cell property, microturbine property, combined heat and power system property, small wind energy property, and thermal energy property. The bill phases out the current credit rate of 30% for investments in fuel cell property, small wind energy property, and fiber-optic solar energy property by reducing it to 26% or 22%, depending on the date that the property is placed in service.