No matter, federal jurisdiction over the environment — including the jurisdiction to impose a
national price on
carbon — may also be based on its taxation power, or on its residual jurisdiction over matters of «
national concern»
under the Peace, Order, and Good Governance (POGG) power.
Policy at the
national level must encourage the deployment of clean energy technologies, and include greenhouse gas emission reduction targets (such as those
under the Paris Agreement),
carbon pricing mechanisms, and investment in energy research, development and demonstration.