If you’ve been tracking the contours of recent legislative sessions under the Gold Dome in Denver, you’ll likely have high expectations about Colorado’s ability to deliver ambitious, even nation-leading, clean energy bills year-after-year, spurring headlines and the envy of other states. Take, for example, last year’s Senate Bill 218 to modernize distribution-system planning, Senate Bill 16 in 2023 to cement a statewide commitment to net-zero emissions by 2050, Senate Bill 264 in 2021 to initiate “Clean Heat Plans” and innovative gas infrastructure planning, or Senate Bill 260 (also in 2021) to create stable multi-year funding streams for clean transportation initiatives—the list goes on.
In a departure from previous back-to-back banner years for the state’s clean energy ambitions, however, this year’s legislative session yielded more muted results. Compared with prior policy wins around the growth of advanced energy and electrification, the 2025 legislative session was an outlier. Several notable clean energy bills faltered before reaching the finish line, while others still did not even get out of the gate.
To be fair, this session presented policymakers with challenges across the board compared to previous sessions: a $1.2 billion budget shortfall, uncertainty around federal action, and ongoing affordability concerns. It is understandable that legislators would be focused on protecting their constituents from the worst impacts of these conditions. This resulted in bold, even controversial, social policies that took over, dwarfing other policy areas.
Still, this was not a year without clean energy legislation.
A disappointing setback for transmission planning
The need to expand electric transmission infrastructure came to the fore with two bills running concurrently. In its original form, bipartisan-backed Senate Bill 127 aimed to:
- Require utilities to include an evaluation of advanced transmission technologies (ATTs), including grid-enhancing technologies, in their electric resource plans (ERPs);
- Allow the Colorado Electric Transmission Authority (CETA) to update its statewide transmission capacity expansion study on an ongoing basis; and
- Better align transmission planning with generation resource planning.
Advanced Energy United (United) played a leading role in drafting and supporting SB 127. But due to fiscal and political considerations, the bill was narrowed to focus solely on setting clear criteria for evaluating ATTs within utilities’ existing transmission planning processes. Despite nearly-unanimous committee support, and a broad coalition behind it, there continued to be utility opposition against it. United and the legislative sponsor opted to pull the bill from the Senate Floor, choosing to regroup over the interim and revisit the effort next year.
Some wins for transmission siting and residential solar
Meanwhile, House Bill 1292—also known as the “NextGen Highways bill”—focused on streamlining siting processes at the Colorado Department of Transportation to lift barriers to co-locating new transmission development in state highway rights-of-way. United supported the bill, alongside a coalition of environmental groups and other clean energy advocates, as a tool to accelerate more transmission capacity. The bill has since passed the legislature and was signed into law by Governor Polis shortly after the legislative session ended.
Senate Bill 299 marked another significant victory for clean energy. Crafted by the solar industry in consultation with many others, the bill outlined consumer protection measures for residential solar covering disclosure materials, sales interactions, and a 3-day cancellation period. It currently awaits a signature from Governor Polis.
Data centers, on-bill financing, clean energy planning, and automated permitting proposals fall short
A late-session bill, Senate Bill 280, sought significant tax breaks for data centers to entice growth in Colorado. The bill garnered opposition from environmental groups and others for lacking alignment with the state’s clean energy and emissions reduction goals and for missing opportunities to incentivize clean energy procurement. It ultimately failed to advance.
Another much-discussed bill, House Bill 1268, proposed a new state-backed on-bill financing program for energy efficiency upgrades. Despite heavy amendments and negotiations, the bill ultimately did not advance to the Senate Floor in the final days of session. In contrast, another clean energy bill targeting the building sector—House Bill 1269, which revises building energy use benchmarking and performance standard requirements and creates a “Building Decarbonization Enterprise”—fared better and was signed by the Governor on May 20.
One of the most anticipated clean energy proposals, “Clean Energy Planning for 2040” (also known as “CEP 2040”), would have codified Governor Polis’ goal of 100% clean energy by 2040 into law. It would have updated requirements within the electric resource planning and clean energy plan processes to ensure utilities are prepared to meet the 100% clean goal affordably and reliably through a combination of diverse advanced energy resources (including zero-emission long lead-time resources like geothermal and long-duration energy storage). But with the request for late introduction and strong opposition from investor-owned utilities, electric co-ops, Chambers of Commerce, and several local governments, the proposal was unable to move forward. United anticipates elements of it will resurface in next year’s policy landscape.
House Bill 1096 also proved contentious. As introduced, it would have required all local governments to implement automated solar permitting. After resistance from city and county groups, the bill was narrowed to focus on cleaning up the existing streamlined solar permitting and inspection grant program.
If this legislative session was anticlimactic for clean energy, then it underscores that much unfinished business remains for the interim and the session to follow.
What we’ll be watching for in the coming months
This Fall, the Colorado Office of Policy, Research, and Regulatory Reform (COPRRR) will publish a sunset review report presenting findings and recommendations related to the reauthorization of the Public Utilities Commission. Subsequent proposed legislation could potentially set the stage for an energy omnibus bill, similar to Senate Bill 236 in 2019. United is participating in the stakeholder engagement process currently underway now.
Additionally, there is room to revisit advanced transmission planning. United will also be watching to see what, if any, activity may result from the findings presented in the forthcoming clean energy siting study required by Senate Bill 212 in 2024.
Even though data center policy stalled out this session, related conversations will almost certainly pick back up in the coming months. United will engage in those discussions to advocate for a policy approach that enables data center energy demand to be met with clean energy resources in a way that works for all ratepayers. It is also worth noting that relevant insights may come out of the Just Transition Solicitation (“JTS”) proceeding going on now that will continue to unfold over the summer, which to date has included a proposal for an “energy park” in Pueblo, powered by renewables and energy storage, to replace the Comanche 3 coal plant. Also on the table is consideration around the PUC’s role in ensuring that rates are fairly structured for large load customers like data centers, so other customers are not inadvertently footing a higher bill for their growth and infrastructure needs.
Although policymakers by and large passed up the opportunity to advance bold clean energy policies this session, the pressure is on for next session to produce better results and fill policy gaps that matter for the state’s clean energy transition. We are entering the final year of Governor Polis’ term in gubernatorial office, where the Energy Office has historically played a leading role on crafting clean energy policies. There is a need for bipartisan leadership in the statehouse willing to champion clean energy issues. With a legislative session now under their belt, the hope is that this year’s freshman class is inspired to take on these pressing issues with fresh urgency and vision. As policymakers set their sights on 2026 and assume the collective mantle on clean energy priorities, and especially as the federal government is poised to reverse course on policies that would support the clean energy industry, it is critical for Colorado to keep leading as a beacon for state action.