THE SENATE is preparing to take up wide-ranging climate and environmental legislation this week that attempts to accelerate the transition to a clean energy future while offering some state residents a measure of relief from the higher costs expected to accompany that transition.

Two bills are expected to come up for votes on Thursday, one dealing with nitty gritty aspects of the clean energy transition and another more narrowly focused measure attempting to curb the use of plastics in everyday life. The plastics bill would ban the use of carry-out plastic bags at retail stores and require stores to charge 10 cents for recycled paper bags, with half of the bag revenue going into a fund for environmental protection initiatives.

The plastics reduction bill would also require non-flushable wipes to be labeled with “Do Not Flush” warnings to curb disruption to the state’s sewer system. Officials say flushed wipes cause roughly $10 million in damage to the system annually.

The bulk of the Senate’s climate bill focuses on making it easier and more predictable to build energy infrastructure projects by concentrating more power in the state’s Energy Facilities Siting Board. Officials say there currently is no deadline for siting decisions; no project has been approved over the last 25 years in less than 15 months and the permitting process can take as long as four years.

Under the Senate bill, state, regional, and local permits for solar, wind, and transmission projects greater than 25 megawatts and battery storage facilities greater than 100 megawatts would be consolidated into a single permit that would have to be approved or rejected by the siting board within 15 months. For smaller clean energy and transmission projects of less than 25 megawatts and storage facilities less than 100 megawatts, municipalities would be the final decision-makers and final decisions would be required in 12 months.

The quicker timetable for decisions could put local residents at a disadvantage in the siting process, so the bill proposes a series of measures to give them some leverage. The bill requires state agencies to come up with standards for analyzing the impact of proposed projects along with standardized community benefit agreements and community engagement requirements. The bill also requires the siting board to prioritize alternatives to new construction projects and preserves limited appeals of siting decisions within the court system.

Senate officials say the provisions dealing with siting were patterned after recommendations put forward by a commission created to establish new siting standards.

Sen. Michael Barrett of Lexington, the chief architect of the climate legislation, said the bill recognizes the transition to clean energy will be costly and have the potential to drive up utility rates. To offset the higher costs, he said, the bill directs state regulators to take a number of steps to rein in other consumer costs and offer utility discounts to more customers.

Under current law, qualifying low-income customers are entitled to hefty discounts on their utility bills. The Senate bill would expand the discounts to include moderate income customers, an approach favored by the Healey administration. The discounts would be paid for by higher assessments on wealthier customers, who at National Grid currently pay an extra $5 a month to finance the low-income discounts and would pay more if the discounts are expanded.

Barrett said the goal of the new expanded discount structure is to preserve the state’s middle class.

The senator said the bill also includes a host of initiatives to quickly reduce the cost of the state’s existing natural gas infrastructure as the economy shifts increasingly to the use of electricity for heat and transportation. The bill also includes measures to sharply restrict any expansion of the networks of natural gas utilities.

The bill includes a number of provisions to decarbonize buildings, electrify transportation infrastructure, expand the state’s electric vehicle charging network, extend electric vehicle rebates for another two years, and revamp the way clean energy is procured.

Current law requires the state’s utilities to enter into contracts with clean energy developers; the Senate bill, according to Barrett, would eliminate the current procurement process and replace it with one where state agencies, not utilities, would negotiate directly with the developers.

The bill also changes the mission of a number of state agencies to put greater emphasis on dealing with climate change.

The bill expands the research focus of the Clean Energy Center to include “carbon removal, embodied carbon reduction, and nuclear power.” Barrett said carbon removal centers on efforts to remove carbon from the atmosphere – an approach being pursued in Iceland. He said nuclear power is definitely part of the state’s clean energy future and more research on fusion reactors is a high priority.

The Senate bill would also revise the enabling statute of the Massachusetts Port Authority, which operates Logan International Airport, to prioritize a reduction in greenhouse gas emissions. It’s unclear what that change would bring about, but the Healey administration has suggested previously that flights to nearby destinations that could be reached by train or bus may need to be eliminated to curb greenhouse gases.

As expected, Barrett said the Senate bill also sides with Gov. Maura Healey, Attorney General Andrea Campbell, Boston Mayor Michelle Wu, and some consumer advocates in calling for the elimination of businesses that sell electricity directly to customers.  Healey and Campbell say the companies have a history of misleading customers and steering them into plans that charge excessive amounts for electricity.

The Senate bill would only allow customers to purchase electricity procured for them by their local utility or by their own city or town. The bill includes a number of provisions that would give utilities more flexibility in purchasing electricity for their customers and theoretically allow them to procure it at a lower cost.

The Senate bills, if they are approved later this week, will then be referred to the House. Rep. Jeffrey Roy of Franklin, Barrett’s counterpart in the House on the Legislature’s Telecommunications, Utilities, and Energy Committee, said it’s unclear what type of bill the House will pursue.

“Siting is our No. 1 issue and what we would add on to that is still being discussed,” he said. He added that the House and Senate are close philosophically on most major siting issues because both he and Barrett served on the commission that recommended policy changes on the issue.

One area where Roy and Barrett clearly disagree is on the elimination of retail electricity suppliers. While Barrett wants to shut down the industry, Roy says he doesn’t want to eliminate all the businesses because of the actions of a few bad apples. “My position hasn’t changed on that,” he said.