Is policy making in the area of energy an expressed power a concurrent power or a reserved power?

The correct answer is "concurrent power".

Concurrent powers are powers shared by both the Federal Government and the State Governments. These powers may be exercised simultaneously by the Federal and State governments in relation to a particular state.

In regards to energy, policies lowering state taxes on renewable energy projects may be enacted by state legislatures. However, if the Federal government deems it necessary, it might simultaneously raise taxes for overall energy companies. This evidently includes renewable energy.

answer: born in saint-dié, in the vosges department, france, he studied law, and was called to the bar at paris in 1854,[2] but soon went into politics, contributing to various newspapers, particularly to le temps. he attacked the second french empire with great violence, directing his opposition especially against baron haussmann, prefect of the seine department. a series of his articles in le temps was later republished as the fantastic tales of haussmannlaxupa (1868).[2]

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