California's rooftop-solar debate is raging again
Two years after slashing compensation for rooftop-solar owners who send power back to the grid, California policymakers are once again looking for ways to contain high and rising electricity rates — which means the accusation that rooftop solar pushes costs onto other utility customers is once again rearing its head. Last month, representatives of the California Public Utilities Commission testified in a state legislative hearing that California’s system for compensating owners of rooftop solar is a primary cause of the state’s rapidly rising utility rates. That testimony is backed by a CPUC report, issued last month in response to an October order from Democratic Gov. Gavin Newsom to find ways to reduce utility-rate increases. Among other potential cost savings, the report proposes further reductions to rooftop-solar compensation that the CPUC has already cut for homes, businesses, farms, and schools in the past two years. The CPUC’s rationale is that solar programs shift costs onto customers who don’t have solar. Linda Serizawa, director of the CPUC’s Public Advocates Office, which is tasked with protecting utility customers, told lawmakers that the state’s rooftop-solar regime has led to non-solar-equipped customers of Pacific Gas & Electric, Southern California Edison, and San Diego Gas & Electric paying $8.5 billion more than they otherwise would have in 2024. That increase accounts for up to a quarter of those customers’ monthly bills, on average, according to the Public Advocates Office. Solar advocates and environmental justice groups have long said this “cost-shift” argument is false. In fact, they say, California utility customers would be paying even higher electric rates if the state hadn’t launched policies back in 2006 that have incentivized California homes, businesses, schools, and other utility customers to install more than 2 million rooftop-solar systems since then. Last week, several pro-solar groups shared new analysis, expanding on research released last year by energy and environmental consulting firm M.Cubed Consulting. The latest round in the “cost-shift” debate comes as the CPUC’s December 2022 decision to cut compensation for newly installed rooftop solar systems has decimated the country’s leading rooftop-solar market, potentially putting the state’s carbon-cutting goals out of reach. About 45% of the state’s solar power now comes from rooftop and distributed sources rather than utility-scale projects, but new rooftop-solar installations have fallen dramatically since the CPUC’s new compensation system went into effect in mid-2023. Without more rooftop solar, “we’re going to have increasing electricity costs, and we’re going to fall short of our clean energy goals,” said Ken Cook, president of the nonprofit Environmental Working Group. The challenge, he said, is to agree on regulatory structures that allow the state to “harness rooftop solar and distributed energy to solve both of these problems.” But the cost-shift argument has short-circuited that kind of policy discussion, said Brad Heavner, policy director for the California Solar and Storage Association, a solar-industry trade group that funded M.Cubed’s cost-shift analyses. “It was devised by the utilities as a way to reframe what rooftop solar is and to put a negative light on it. And it has worked.” Now, with mounting pressure to reduce utility rates, rooftop-solar advocates fear the argument will be used once again to justify further cuts to an industry they view as crucial not only to climate goals but as a net benefit — not cost — to utility customers. What’s the cost shift? The cost-shift argument was initially put forward by the Edison Electric Institute, a trade group representing U.S. electric utilities. Utilities pay for building and maintaining the power grid through the rates they charge customers. The cost-shift thesis argues that paying some customers for their rooftop-solar power unfairly shifts the burden of covering the costs of keeping utilities running onto other customers. But Richard McCann, a founding partner at M.Cubed, argues that California’s nation-leading rooftop-solar resource has saved customers as much as $1.5 billion in 2024 through savings accrued over the past two decades. The reason, in his view, is simple: More rooftop solar means utilities need to buy less energy from other resources and build less power lines and other grid infrastructure to meet customers’ power demand. Back in 2005, the California Energy Commission forecasted that the state’s peak demand for electricity — the primary driver of utility costs for generation and grid capacity that are passed on to customers — would grow from about 45 gigawatts to more than 60 GW by 2022 or so, McCann said. But peak electricity demand on the statewide grid operated by the California Independent System Operator (CAISO) has grown far more slowly. The system has instead topped out at a record-setting peak of 52 GW in September 2022 — only about 2 GW over the previous record set in 2006. Over that same time, the state’s net-metering policies have incentivized millions of customers of the state’s three big utilities to install solar panels, he said. Much of the state’s peak grid demand coincides with hot summer afternoons — the same time that rooftop solar produces the most electricity. CAISO does not directly track how much power rooftop solar generates across millions of California homes and businesses, McCann noted. But the simultaneous trends of lower-than-forecasted peak demand and growing rooftop-solar resource indicate that “rooftop solar has displaced the peak load demand in the CAISO system and kept the CAISO load flat over that same time period,” he argued. If that’s the case, customers investing in rooftop solar have helped the state’s utilities avoid investing in new generation, transmission, and distribution, potentially saving ratepayers billions of dollars, he said. “Rates would be even higher than what they are now if rooftop solar had not been present.” Who owns the solar power used at home? McCann’s view, supported by most environmental advocates, the solar industry, and some energy analysts, is hotly contested by utilities as well as independent analysts who have championed the cost-shift thesis. In the latter group’s view, rooftop solar is a more expensive and less efficient alternative to building utility-scale solar power plants and transmission grids. Shifting money from those larger-scale alternatives not only pulls money from customers without solar to those with solar, they argue, but represents a lost opportunity for utilities to invest in more cost-effective clean power. Severin Borenstein, head of the Energy Institute at the University of California, Berkeley’s Haas School of Business, is a key proponent of the cost-shift theory. In January, Borenstein published a paper challenging McCann’s take on the value of rooftop solar, citing “fundamental conceptual errors that undermine most of its points.” Borenstein said that a proper analysis finds that in 2024 solar net-metering pushed about $4 billion in costs onto utility customers who don’t have solar. That’s not nearly as high as the $8.5 billion figure from the CPUC’s Public Advocates Office, but it’s still a net cost rather than a benefit to customers at large. In February, McCann published a reply to Borenstein’s critique, delving into his point-by-point differences of opinion on how these costs should be calculated. Much of the dispute is highly technical in nature. And because these analyses rely on heavily varied assumptions — including what would have happened if the past 20 years of rooftop-solar policy hadn’t played out the way they have — many of the conflicts between the two sides on precise numbers can’t be answered definitively. That uncertainty has led both sides to accuse the other of using intentionally misleading data and methods. McCann acknowledged that his initial analysis last year miscalculated the benefits that he believes rooftop solar has delivered to customers of the state’s three big utilities. He originally calculated $2.3 billion worth of benefits in 2024, rather than the $1.5 billion that emerged from his latest analysis. The in-the-weeds exchange between McCann and Borenstein reveals a deeper disagreement at the heart of their vastly different estimates — one that cost-shift foes say California regulators have failed to fully acknowledge. It centers on a simple question: When a household generates solar power at the same time as it’s using electricity from the grid, who owns that solar?
Two years after slashing compensation for rooftop-solar owners who send power back to the grid, California policymakers are once again looking for ways to contain high and rising electricity rates — which means the accusation that rooftop solar pushes costs onto other utility customers is once again rearing its head.…
Two years after slashing compensation for rooftop-solar owners who send power back to the grid, California policymakers are once again looking for ways to contain high and rising electricity rates — which means the accusation that rooftop solar pushes costs onto other utility customers is once again rearing its head.
Last month, representatives of the California Public Utilities Commission testified in a state legislative hearing that California’s system for compensating owners of rooftop solar is a primary cause of the state’s rapidly rising utility rates.
That testimony is backed by a CPUC report, issued last month in response to an October order from Democratic Gov. Gavin Newsom to find ways to reduce utility-rate increases. Among other potential cost savings, the report proposes further reductions to rooftop-solar compensation that the CPUC has already cut for homes, businesses, farms, and schools in the past two years.
The CPUC’s rationale is that solar programs shift costs onto customers who don’t have solar. Linda Serizawa, director of the CPUC’s Public Advocates Office, which is tasked with protecting utility customers, told lawmakers that the state’s rooftop-solar regime has led to non-solar-equipped customers of Pacific Gas & Electric, Southern California Edison, and San Diego Gas & Electric paying $8.5 billion more than they otherwise would have in 2024. That increase accounts for up to a quarter of those customers’ monthly bills, on average, according to the Public Advocates Office.
Solar advocates and environmental justice groups have long said this “cost-shift” argument is false. In fact, they say, California utility customers would be paying even higher electric rates if the state hadn’t launched policies back in 2006 that have incentivized California homes, businesses, schools, and other utility customers to install more than 2 million rooftop-solar systems since then.
Last week, several pro-solar groups shared new analysis, expanding on research released last year by energy and environmental consulting firm M.Cubed Consulting.
The latest round in the “cost-shift” debate comes as the CPUC’s December 2022 decision to cut compensation for newly installed rooftop solar systems has decimated the country’s leading rooftop-solar market, potentially putting the state’s carbon-cutting goals out of reach. About 45% of the state’s solar power now comes from rooftop and distributed sources rather than utility-scale projects, but new rooftop-solar installations have fallen dramatically since the CPUC’s new compensation system went into effect in mid-2023.
Without more rooftop solar, “we’re going to have increasing electricity costs, and we’re going to fall short of our clean energy goals,” said Ken Cook, president of the nonprofit Environmental Working Group. The challenge, he said, is to agree on regulatory structures that allow the state to “harness rooftop solar and distributed energy to solve both of these problems.”
But the cost-shift argument has short-circuited that kind of policy discussion, said Brad Heavner, policy director for the California Solar and Storage Association, a solar-industry trade group that funded M.Cubed’s cost-shift analyses. “It was devised by the utilities as a way to reframe what rooftop solar is and to put a negative light on it. And it has worked.”
Now, with mounting pressure to reduce utility rates, rooftop-solar advocates fear the argument will be used once again to justify further cuts to an industry they view as crucial not only to climate goals but as a net benefit — not cost — to utility customers.
What’s the cost shift?
The cost-shift argument was initially put forward by the Edison Electric Institute, a trade group representing U.S. electric utilities. Utilities pay for building and maintaining the power grid through the rates they charge customers. The cost-shift thesis argues that paying some customers for their rooftop-solar power unfairly shifts the burden of covering the costs of keeping utilities running onto other customers.
But Richard McCann, a founding partner at M.Cubed, argues that California’s nation-leading rooftop-solar resource has saved customers as much as $1.5 billion in 2024 through savings accrued over the past two decades. The reason, in his view, is simple: More rooftop solar means utilities need to buy less energy from other resources and build less power lines and other grid infrastructure to meet customers’ power demand.
Back in 2005, the California Energy Commission forecasted that the state’s peak demand for electricity — the primary driver of utility costs for generation and grid capacity that are passed on to customers — would grow from about 45 gigawatts to more than 60 GW by 2022 or so, McCann said.
But peak electricity demand on the statewide grid operated by the California Independent System Operator (CAISO) has grown far more slowly. The system has instead topped out at a record-setting peak of 52 GW in September 2022 — only about 2 GW over the previous record set in 2006.
Over that same time, the state’s net-metering policies have incentivized millions of customers of the state’s three big utilities to install solar panels, he said. Much of the state’s peak grid demand coincides with hot summer afternoons — the same time that rooftop solar produces the most electricity.
CAISO does not directly track how much power rooftop solar generates across millions of California homes and businesses, McCann noted. But the simultaneous trends of lower-than-forecasted peak demand and growing rooftop-solar resource indicate that “rooftop solar has displaced the peak load demand in the CAISO system and kept the CAISO load flat over that same time period,” he argued.
If that’s the case, customers investing in rooftop solar have helped the state’s utilities avoid investing in new generation, transmission, and distribution, potentially saving ratepayers billions of dollars, he said. “Rates would be even higher than what they are now if rooftop solar had not been present.”
Who owns the solar power used at home?
McCann’s view, supported by most environmental advocates, the solar industry, and some energy analysts, is hotly contested by utilities as well as independent analysts who have championed the cost-shift thesis.
In the latter group’s view, rooftop solar is a more expensive and less efficient alternative to building utility-scale solar power plants and transmission grids. Shifting money from those larger-scale alternatives not only pulls money from customers without solar to those with solar, they argue, but represents a lost opportunity for utilities to invest in more cost-effective clean power.
Severin Borenstein, head of the Energy Institute at the University of California, Berkeley’s Haas School of Business, is a key proponent of the cost-shift theory. In January, Borenstein published a paper challenging McCann’s take on the value of rooftop solar, citing “fundamental conceptual errors that undermine most of its points.”
Borenstein said that a proper analysis finds that in 2024 solar net-metering pushed about $4 billion in costs onto utility customers who don’t have solar. That’s not nearly as high as the $8.5 billion figure from the CPUC’s Public Advocates Office, but it’s still a net cost rather than a benefit to customers at large.
In February, McCann published a reply to Borenstein’s critique, delving into his point-by-point differences of opinion on how these costs should be calculated. Much of the dispute is highly technical in nature. And because these analyses rely on heavily varied assumptions — including what would have happened if the past 20 years of rooftop-solar policy hadn’t played out the way they have — many of the conflicts between the two sides on precise numbers can’t be answered definitively.
That uncertainty has led both sides to accuse the other of using intentionally misleading data and methods. McCann acknowledged that his initial analysis last year miscalculated the benefits that he believes rooftop solar has delivered to customers of the state’s three big utilities. He originally calculated $2.3 billion worth of benefits in 2024, rather than the $1.5 billion that emerged from his latest analysis.
The in-the-weeds exchange between McCann and Borenstein reveals a deeper disagreement at the heart of their vastly different estimates — one that cost-shift foes say California regulators have failed to fully acknowledge. It centers on a simple question: When a household generates solar power at the same time as it’s using electricity from the grid, who owns that solar?