The wind and solar industries have always suffered from the short-term nature of subsidies, with federal tax credits often extended in nail-biting one-year increments. Last year’s climate bill changed that, giving the industry subsidies that last at least a decade. But just as policy winds blow in their favor, two critical growth drivers—interest rates and equipment costs—are moving in the wrong direction. Wind and solar projects are especially sensitive to rates because debt can comprise as much as 85% to 90% of capital expenditures. Renewable developers have known only low rates for most of their history. Nearly all U.S. utility-scale solar facilities and 85% of onshore wind farms were installed since 2009, during which period the target federal-funds rate was close to 0% in eight out of 13 years. Not any more: After the most recent hike, rates are the highest since 2007. Renewable energy projects tend to be financed with floating-rate loans that rise and fall with the benchmark interest rate. Thankfully, most of those projects are well-shielded from rate risk because lenders require them to hedge at least 75% of their loans through swaps, according to Elizabeth Waters, managing director of project finance at MUFG. Most ended up hedging 90-95% to lock in low rates, she noted. But those swaps won’t help new projects. Some new solar and wind projects facing higher borrowing costs than when they were planned might not make it off the drawing board. Borrowing isn’t the only thing that costs more. Following years of price declines thanks to technology and economies of scale, equipment is getting more expensive too. Trade policies aimed at Chinese manufacturers have caused delays and shortages for the solar industry, which relies heavily on the country for its components. German utility RWE, an active developer in the U.S., said in its annual report released last week that imports of solar modules from Asia are now subject to “stringent checks” and said it could fall behind on its expansion plans if the U.S. continues to “impede the procurement of solar panels.” After falling to a record low in 2020, the average price of a solar photovoltaic system rose in 2021 and then again in 2022, according to data from the Solar Energy Industries Association and Wood Mackenzie. Meanwhile, the average cost to build an onshore wind farm in the U.S. rose in 2020 and 2021 before leveling off last year, according to data from BloombergNEF. Supply-chain issues and interconnection delays already started slowing the clean power industry last year: In 2022 it installed 25.1 Gigawatts of total capacity, a 16% decline from a year earlier, according to the American Clean Power Association, which tracks solar, wind and energy storage. While that’s still enough to meet roughly half of Texas’ electricity demand, it was nonetheless below expectations–though part of the drop was driven by an preplanned phase-down for tax credits commonly used by the wind industry before the Inflation Reduction Act was passed. Ultimately, solar and wind’s ability to absorb cost and interest-rate hikes depends on how willing utilities and corporations are to pay higher prices. Many onshore wind and solar projects have been able to renegotiate pricing on their power purchase agreements because demand is robust, according to industry executives. But cracks are showing for offshore wind, which is more exposed to rising costs and rates because it takes longer to develop. BloombergNEF estimates that the weighted average cost of capital for U.S. offshore wind projects rose to 5.25% in 2022 from 4.41% in 2020.