BOSTON -- At the start of 2020, it seemed almost inevitable that the Legislature would send Gov. Charlie Baker some form of climate change legislation by this summer. Now, with the pandemic demanding a massive share of legislative energy and with time for significant lawmaking ticking away, advocates are urging legislators not to squander the opportunity.

On Tuesday, members of the Northeast Clean Energy Council, the Alliance for Business Leadership, Chambers for Innovation and Clean Energy, and the Climate Action Business Association convened lawmakers, administration officials, business owners and industry experts to discuss clean energy priorities and how to advance a clean energy agenda despite the pandemic. Following a speaking program, 165 business owners and executives planned to meet virtually with a slew of key lawmakers to discuss specifics.

Climate legislation had figured to be a central focus of the legislative session's home stretch since the House and Senate had each passed major climate-related bills before most business was put on pause. On the same day in January, Gov. Charlie Baker, House Speaker Robert DeLeo and Senate President Karen Spilka all declared their support for net-zero carbon emissions by 2050, a policy that climate change activists have been pushing for years.

Both branches have passed climate-related bills, but the shared goal for 2050 still hasn't been formalized within the Legislature. That's one topic that is ripe for action before the end of the session, NECEC President Peter Rothstein said.

"There's also opportunities to expand policies for municipal resiliency investments, the passage of the speaker's GreenWorks initiative," Rothstein said. "It's an important time to also be providing some expanded funding support for the Massachusetts Clean Energy Center, so that that agency can continue to leverage public and private funding to accelerate the commonwealth's clean energy sector. On offshore wind, very important and emerging sector, it's also important to look at opportunities for additional competitive bids for offshore wind, along with Class I renewables, to continue critical growth of those sectors."

The House last July unanimously approved a roughly $1.3 billion bill -- the so-called GreenWorks bill -- centered around grants to help communities adapt to climate change impacts, and at the end of January the Senate overwhelmingly passed a suite of climate bills that called for net-zero carbon emissions by 2050, and set deadlines for the state to impose carbon-pricing mechanisms for transportation, commercial buildings and homes.

With formal sessions slated to stop after July 31 and the House and Senate needing to come together to get something to the governor's desk by then, lawmakers, climate advocates and business groups have been busy trying to influence a potential end-of-session climate policy bill.

"In January of this year, the state Senate passed An Act Setting Next-Generation Climate Policy, it's a bill that's currently over in the House where undoubtedly folks have very good ideas of their own," Sen. Michael Barrett, the Senate chair of the Telecommunications, Utilities and Energy Committee, said during Tuesday's virtual event. "The important thing to the Senate is not that its particular prescriptions be adopted in every respect, but that we get a bill in the year 2020 -- an ambitious bill that really moves the ball up the field."

Barrett's House co-chair, Rep. Tom Golden, agreed that the Legislature must pass a climate bill by the end of 2020 but suggested that the pandemic might have altered the way the House thinks about some of the issues at play.

"The House of Representatives is eager to move forward, but one thing that I believe we have to have a discussion about is what has happened over the past few months, with the financial concerns or financial catastrophe that we're now experiencing. We're looking at anywhere between $6 to $7 billion in possible revenue shortfalls, and a loss of, I believe the latest a number I'd seen was, over 17,000 jobs in the clean energy sector," Golden said.

He continued, "The House of Representatives has taken an approach for some time with GreenWorks ... I'm looking forward to working with Senator Barrett on moving our vision as well as the Senate's vision towards a final, rectifying a final piece of legislation. I think it's vitally important that we finish this before 2020 ends."

Barrett and Golden each mentioned the importance of getting a bill done by the end of 2020, but the reality is that, as of right now, the House and Senate only have until July 31 to hold formal sessions and take roll call votes. Though there had been some talk about extending the end of formal sessions beyond July 31, an extension has not materialized and lawmakers on both sides of the building have referred to July 31 as a deadline for action.

"Tomorrow will be July first. July 31 is, as we have this conference, the last day of session unless we change our rules. So thinking about that, we've got 30 days to act and put something into statute that is codified and will do the job that we need to have done," Sen. Marc Pacheco, who has been rallying colleagues to commit to getting a climate bill to the governor by the end of July, said. "Now, we don't need a whole lot of new policies, they're already out there. We know what some of the options are, it's just a matter of the Legislature having the political will to act on these issues."

With the policies included in the House's GreenWorks bill and in the Senate's package of bills well-known, advocates and interest groups have been busy trying to influence which ones might survive into a final bill.

Many of the business groups that participated in the virtual event and meetings Tuesday support key parts of the Senate bill and also want to see action on a Rep. Joan Meschino bill (H 832 redrafted as H 3983) that would create a roadmap to the state's 2050 climate goals.

Last week, a coalition of some of the most powerful business and trade groups in the state sent a letter to House leaders making clear that they do not want the House to go along with some of the central features of the Senate's legislation.

"Ultimately, we believe this bill would harm consumers and businesses and undermine our smart growth objectives at a time our economy can least afford even the smallest step backwards -- without making the meaningful emissions reductions we need to reverse the effects of climate change," the Mass. Coalition for Sustainable Energy wrote.

This week, Barrett and Sen. Jason Lewis responded by blasting the coalition as a fossil fuel industry front that was looking to exploit an opening presented by the COVID-19 pandemic, and defended the approach the Senate took in its bill in January.

"The Senate's approach to reducing greenhouse gas emissions is radical not in its ideology but in its seriousness; we're determined to get emissions down across the Massachusetts economy, transportation and buildings included," Barrett and Lewis wrote. "We should add that the senators who wrote the legislation sat down with a good many commercial interests, listened to what they had to say, and made changes. At the time of the bill's final passage -- with the votes of both Democrats and Republicans, and with only two dissents in the 40-member Senate -- its seriousness of purpose seemed to impress the business community without unsettling it."