Synopsis As Introduced Amends the Public Utilities Act. Provides that natural gas utilities shall implement cost-effective energy efficiency measures to meet specified cumulative natural gas savings requirements. Provides that a natural gas utility may meet 1/3 of the annual energy efficiency portfolio requirement through electricity savings associated with combined heat and power systems using an electricity-to-gas savings conversion factor, which shall be established by the Illinois Commerce Commission no later than March 1, 2010. Provides that notwithstanding the requirements of specified provisions, a natural gas utility shall limit the amount of energy efficiency implemented in any 3-year reporting period established by specified provisions by an amount necessary to limit the estimated average increase in the amounts paid by retail customers in connection with natural gas service to no more than 2% in the applicable 3-year reporting period. Provides that natural gas utilities shall be responsible for overseeing the design, development, and filing of their efficiency plans with the Commission. Contains provisions concerning the implementation of energy efficiency measures by the Department of Commerce and Economic Opportunity. Provides that each gas utility shall file an energy efficiency plan with the Commission to meet the energy efficiency standards for through May 31, 2014. Contains provisions concerning contributions by a gas utility into the Low-Income Home Energy Assistance Program. Provides that not later than January 1, 2010, the Commission shall, after an opportunity for public comment, provide the General Assembly with recommended modifications to the Act to foster statewide coordination and consistency between statutorily-mandated natural gas and electric energy efficiency programs to achieve specified goals. Effective immediately.