; and (2) natural gas savings targets for retail natural gas suppliers. (b) Consultation The Secretary shall carry out this section in consultation with the Administrator of the Environmental Protection Agency. (c) Requirements With respect to targets under subsection (a): (1) The targets shall require each retail electric energy supplier to secure annual electricity savings, and each retail natural gas supplier to secure annual natural gas savings, of a set percentage of the quantity of electricity or natural gas sold in the most recent year to retail customers. (2) The electricity savings and natural gas savings shall be achieved through end-use efficiency improvements at customer facilities. (3) The targets are cumulative. Each year’s electricity savings or natural gas savings shall be achieved in addition to the previous years’ savings. (4) For each of calendar years 2023 through 2030, the targets are as follows: Calendar Year Cumulative Electricity Savings Percentage Cumulative Natural Gas Savings Percentage 2024 0.375 0.25 2025 1.125 0.60 2026 2.25 1.05 2027 3.75 1.55 2028 6.25 2.38 2029 8.75 3.21 2030 11.25 4.05 (d) Required percentages after 2030 The Secretary may, upon petition or upon the Secretary’s own initiative, increase the required percentage of end-user electricity savings or natural gas savings for years after 2030. (e) Market-Based Trading System The Secretary shall allow suppliers to achieve the required percentage of end-user electricity savings or natural gas savings under this section through a market-based trading system. (f) Rule of construction Nothing in this section shall be construed to preempt or limit State actions to enhance renewable energy generation or energy efficiency. . (b) Conforming amendment The table of contents for the Public Utility Regulatory Policies Act of 1978 is amended by inserting after the item relating to section 608 the following: Sec. 609. Rural and remote communities electrification grants. Sec. 610. National renewable energy standard. Sec. 611. National