Want to Solve Climate Change? First Fix Muni Bonds.

Decarbonizing the global economy requires replacing stuff that emits carbon dioxide with stuff that doesn’t. At its heart, this challenge is financial: All these high-emitting assets ― coal plants, gas stoves, airplanes ― were at some point financed into existence by investors seeking returns. Climate policymakers’ greatest challenge is not just figuring out how to phase out existing, dangerous capital investments in fossil fuels, but also how to finance into existence new, climate-stabilizing clean assets.

This is all much easier said than done. Central banks’ high interest rates are strangling clean energy and adaptation infrastructure investments in the United States and abroad. Recent struggles to develop offshore wind and small modular nuclear reactors in the United States exemplify how deeply hesitant private developers are to commit to long-term capital expenditures. Investors view these projects as too risky, their expected profits too low to meet their minimum return thresholds. Absent policies to stabilize supply chains and other factors affecting the financing environment for clean energy, the United States ― to say nothing about the rest of the world ― won’t meet its climate goals.

The Inflation Reduction Act is, to its credit, a paradigm-shifting attempt to finance better, cleaner stuff. One of the most potentially transformative initiatives in the IRA is, in fact, financial: the Greenhouse Gas Reduction Fund offers $27 billion in startup capital to state green banks, community development financial institutions, and nonprofits to lend to decarbonization projects primarily in vulnerable communities.

By any standard, the GGRF is an incredible infusion of cash into nascent sectors that might otherwise be neglected by mainstream investors, including community-scale renewable energy and building weatherization. Most of that cash was awarded in early April, including $14 billion divided among three separate clean energy financing coalitions made up of green banks, impact investors, and CDFIs; and $6 billion divided among various technical assistance providers for project development in low-income areas. GGRF funding recipients can use their awards to finance all kinds of community improvements ― not just through grants, but also through debt and equity. In the process, they will make a market for investments in local climate mitigation and resilience, particularly in vulnerable communities.

The GGRF is about more than simply using this seed funding to make private projects profitable. The truth is, there aren’t that many private investors rushing to structure local decarbonization projects ― not even because they don’t want to enter these market segments, but because they’re really just too busy to try anything unconventional. Some markets, like those for rooftop solar assets, are fairly standardized and liquid, insofar as investors can tranche and trade rooftop solar loans like government bonds or mortgages.

But the nascent markets for many other kinds of mitigation and resilience investments like home retrofits are illiquid. Making them liquid — and getting investors interested — requires GGRF awardees to underwrite, structure, and sequence project development themselves. They must set lending guidelines, standardize financial products, and create architectures for risk management where none exist.

If GGRF recipients build up significant financial and legal capacities to finance community decarbonization, not to mention the technical and regulatory expertise needed to coordinate state and federal funding sources in the process, then they will position themselves to help alleviate significant constraints on the flow of financing toward local decarbonization projects. This is how the IRA promises state and local governments the chance to provide unprecedented liquidity to green investments.

Cities and states currently get the liquidity they need to fund most of our public infrastructure and services through the American municipal bond market. Why not use this market to finance decarbonization, too?

It’s a good idea — except that municipal bond markets are dysfunctional. Cities and states rely heavily on private banks to structure their municipal bonds and sell them to private investors, and on credit rating agencies to certify them; these dependencies have historically forced local governments to tailor their bond issuances to the interests of a few private buyers, which are skewed against spending on longer-term priorities with lower expected returns.

Borrowing big is more often punished than rewarded, especially where governments already have smaller tax bases and less borrowing capacity. In 2018, the rating agency Moody’s downgraded Jackson, Mississippi on account of its “financially stressed” water system and its residents’ low average incomes, raising the city’s future cost of borrowing on bond markets. Last year, its water system spiraled into crisis on account of severe underinvestment, leading to a foregone conclusion: At a time when Jackson, a predominantly black city, needed more low-cost, long-term investment to fix its infrastructure, its government was structurally unable to raise enough of it.

Increasingly frequent climate disasters will set in motion the same process again and again across the country. Greater perceived climate risks are increasing municipal borrowing costs and insurance premiums, thereby driving investment away from vulnerable areas, preventing communities from investing in adaptation and resilience, and increasing their future vulnerability. Proactive disaster prevention policy requires breaking this financial doom loop.

It doesn’t help that municipal bonds are a volatile asset class, seeing sharp price drops and prolonged sell-offs during periods of market uncertainty and, lately, rapid interest rate hikes. Their dependence on risk-averse private buyers is a primary culprit. Indeed, private investors’ muni bond fire sales at the start of the pandemic nearly broke this market. Had it not been for the Federal Reserve’s emergency creation of the Municipal Liquidity Facility, which committed the Fed to buying muni bonds that no other investor wanted to hold, cities and states would not have been able to fund crucial social and community services, pay employees, and undertake necessary capital investments. The mere announcement of this backstop program preserved cities’ ability to raise debt during the first phase of the pandemic, but Congress forced it to wind down at the end of 2020.

That’s a shame: Absent this kind of backstop for public bond markets to stabilize local governments’ long-term borrowing costs, policymakers literally cannot secure the liquidity they need to keep their climate promises. There really is no way to flood-proof New York, storm-proof Miami, summer-proof Amtrak, or manage wildfire out West without the long-term public debt finance that would allow states and cities to spend responsibly and consistently on resilience.

This is a problem not just for long-term adaptation and resilience investments, but also for the mitigation investments the IRA is designed to facilitate. Considering that green banks, state financing authorities, and public-sector power developers will have to issue considerable amounts of debt to accelerate the deployment of renewable energy ― and especially because no comprehensive decarbonization program can neglect public housing or schools, which finance themselves via municipal bonds ― state and federal policymakers should not let their investment priorities fall victim to the whims of our illiquid, volatile public debt markets.

Where climate mitigation is concerned, there are some provisions of the IRA that demonstrate how rewiring the financial system to power decarbonization works in practice. Tax credits that pump a functionally unlimited amount of money into private and public clean energy development allow developers to take on more debt at better terms, facilitating greater investment. (Bonus tax credits for investments in disadvantaged communities should help mitigate against geographic biases, too.) And expanded lending authority at the Department of Energy makes financing higher-risk, longer-term decarbonization investments of all kinds vastly less expensive. The United States has seen over $200 billion in new decarbonization investments in the past year, suggesting that, despite the lack of finalized regulations on tax credit financing and “chaining,” a set of provisions that could allow public and nonprofit entities to engage in tax credit financing of private projects, the Biden administration’s political down payment on decarbonization is already paying off.

Not in every sector, though. Private investors are fickle, risk-averse, and face considerable restrictions on where they can put direct money. The developers they finance, particularly those behind the most ambitious decarbonization projects, are under similar pressures. As Ørsted, the world’s leading offshore wind developer, retreats from projects in the U.S. and elsewhere, its CEO has admitted that “what our investors need” is for Ørsted to “create value.” If expected returns aren’t high enough, then its projects won’t pencil out. Time is of the essence; this outcome shouldn’t be acceptable.

New York’s recently passed Build Public Renewables Act mandates that New York’s public energy authority build renewable energy itself for just this reason — its proponents doubted that relying on private developers made good business sense. But it may not have passed without the IRA’s financial firepower behind it. The IRA allows the public sector to access many of the same decarbonization incentives it gives private firms, balancing the playing field and empowering transformative public sector policymaking.

The public sector can also compete against risk-averse private lenders to finance project development — public financing authorities can lend for longer, on cheaper terms, and with a higher risk tolerance than most private lenders could. By offering cost-share agreements, low-cost construction loans, equity injections to buy out troubled projects, or even by building up critical component stockpiles, the public sector can set the pace of the transition.

To that end, the IRA empowers state and local governments and community lenders to seed ambitious decarbonization projects of all types and sizes where private investors alone might hesitate. This brings us back to the GGRF and all it could do for local decarbonization ― and to carveouts in the Department of Energy’s lending authorities which enable state green banks to pass on extremely low-interest loans to eligible project developers. So long as public and private entities take the effort to access them, these programs create considerable liquidity for ambitious mitigation programs and resilience investments.

But the GGRF does not target larger infrastructure improvements, and the IRA’s other grant programs for adaptation and resilience, however ambitious they may be on the scale of U.S. history, are also wholly inadequate. If policymakers and legislators want to make nationwide climate adaptation feasible, they will still have to fix public debt markets.

Maximizing the potential of the IRA to replace bad assets with better ones requires giving local and state governments the chance to throw money at mitigation and adaptation problems that money can actually solve. Leave the financial system as is, however, and the private investors that mediate it will steer the benefits of decarbonization and adaptation toward the communities wealthy enough to make doing so a good investment. Meanwhile, the communities experiencing climate disasters first and worst ― spread across underinvested rural and urban pockets, here and globally ― will struggle to secure the long-term financing they urgently need both to lessen their contributions to climate change and also to prepare for its inevitable effects.

The financial status quo forces a kind of trickle-down decarbonization that is wholly inadequate to the scale of the climate challenge. Responsible climate policymaking, then, requires the elimination of this liquidity constraint everywhere, to the greatest extent possible, and the creation of coordination mechanisms to ensure that what people need is what gets built. Public liquidity is, without a doubt, a public good.