Tag Archives: sustainability

Response to Borenstein’s critique of our assessment of the benefits of rooftop solar

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Severin Borenstein at the Energy Institute at the Haas Business School posted a reply[1] to our analysis[2] of the Public Advocates Office’s claim[3] of a large “cost shift” created by rooftop solar customers to other customers. Here is my extended reply to Borenstein’s critique.

  • Issues of agreement: Borenstein acknowledges that the PAO used an incorrect capacity factor to calculate the total amount of rooftop solar generation. He also acknowledged that the monthly bill payments from rooftop solar customers should be included in the calculation, an error that both PAO and he has previously committed. Further, he agreed, with caveats, that the rate reductions and subsidy savings for low-income CARE customers should be included. Those elements alone add up to reducing PAO’s claimed cost shift approaching $2 billion or 25%
  • Self generation: Borenstein and the PAO ignore the fact that self generation is not included in any utility resource planning. Rooftop solar generation is counted in load forecasts as a load reduction just like energy efficiency. Grid investments, generation capacity and operational decisions such as reserve margins all focus solely on metered load that excludes all self generation.. Borenstein mistakenly asserts that grid and self-provided power mingles, obviating the right to self generation. If there is generation and consumption onsite at the same time, those electrons do not touch the grid. Along with the fact that the energy does not mix, legal precedents and analysis by leading regulators contradict Borenstein’s (and PAO’s) position. Further, the NEM tariffs explicitly recognize the right to self generate for the term of the tariff.
  • Historic utility savings: Borenstein, like PAO, creates a confusing “apples-to-oranges” comparison of historic costs vs. projected future savings. The Avoided Cost Calculator does not include information about historic costs and therefore cannot be used to calculate historic savings from previously installed rooftop solar systems. Using this tool to estimate how much utilities would have spent were it not for previous solar installations is highly inaccurate. The ACC does not have this data. Rates do not reflect future value. In addition, Borenstein ignores suppression of peak load growth since 2006 by the addition of rooftop solar. He confuses the total customer peak served by all resources including rooftop solar with the CAISO metered peak served only by utility resources, asserting that rooftop solar provides little value to meeting today’s metered peak. Only by recreating the costs that would have been borne by ratepayers over the last two decades can the actual savings and reduction in rates be calculated.
  • Customer Bill Payment: While he agrees bill payments should be included in the PAO’s analysis, but he focuses only on the cost-shift burden and fails to acknowledge the contribution to utility fixed costs made by these customers. The appropriate comparison is customer bill payments compared to utility fixed costs per customer. My analysis shows solar customers more than cover utility fixed costs.
  • Overall savings provided to all ratepayers from rooftop solar conservatively is $1.5 billion in 2024.

Further observations

To start, the focus of our analysis is on the Public Advocates Office (PAO) report issued in August 2024. We used PAO’s own spreadsheet as the base of the analysis and supplemented that with other sources. The critique of Borenstein’s analysis is collateral and, compared to that of the PAO analysis, is limited to the questions of self generation and how to calculate the cost savings created by rooftop solar. His capacity factor, inclusion of CARE customers and applicable retail rates are much closer to those that I used. I pointed out in my blog post that Borenstein had not made the mistakes that PAO had made on technical issues.

Yet on the other hand, Borenstein’s own spreadsheet was documented in a small, cryptic “Readme” file,[4] and the final calculation of the “cost shift” was a set of raw values with no internal calculations. When I recreated those calculations, I could not exactly duplicate what Borenstein presented. Similarly, the PAO’s spreadsheet was sparse on documentation. Most of what is shown in my workpapers are my own additions, not PAO’s.

Finally, many of the sources that Borenstein refers to are in fact himself. The NRDC citation relies on his own Next10 report. The LAO report cites back to his own blog post. He refers to his own critique of NEM from four years ago to criticize the NEM 3.0/NBT framework that was finalized two years later. That analysis is likely now obsolete.

As for being an “industry consultant,” a sample of our recent clients shows their diversity where we have worked for environmental organizations, water districts and utilities, agricultural and business associations intervening at the CPUC, CCAs, county governments, tribes, regional energy networks, state agencies, and lately solar advocates. We must present analyses that are sufficiently balanced so as to be credible with all of these different stakeholders. Further, our work is carefully documented and our data and assumptions completely transparent, unlike the work of Borenstein or the PAO.

(I will also note that Borenstein has apparently blocked me on LinkedIn so that he can exclude me from the discussion taking place on his post there.)

[1] See https://energyathaas.wordpress.com/2025/01/27/guess-what-didnt-kill-rooftop-solar/

[2] See https://mcubedecon.com/2024/11/14/how-californias-rooftop-solar-customers-benefit-other-ratepayers-financially-to-the-tune-of-1-5-billion/

[3] See https://www.publicadvocates.cpuc.ca.gov/-/media/cal-advocates-website/files/press-room/reports-and-analyses/240822-public-advocates-office-2024-nem-cost-shift-fact-sheet.pdf

[4] Published with his April 2024 blog post.

Davis, like many communities, needs a long-term vision

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The Davis Vanguard published an article about the need to set out a vision for where the City of Davis wants to go if we want to have a coherent set of residential and commercial development decisions:

How do we continue to provide high quality of life for the residents of Davis, as the city on the one hand faces fiscal shortfalls and on the other hand continues to price the middle class and middle tier out of this community? A big problem that we have not addressed is the lack of any long term community vision. 

The article set out a series of questions that focused on assumptions and solutions. But we should not start the conversation with choosing a growth rate and then picking a set of projects that fit into that projection.

We need to start with asking a set of questions that derive from the thesis of the article:

  • – What is the composition that we want of this community? What type of diversity? How do we accommodate students? What are the ranges of statewide population growth that we need to plan for?
  • – To achieve that community composition, what is the range of target housing price? Given the projected UCD enrollment targets (which are basically out of our control), how much additional housing is needed under different scenarios of additional on campus housing?
  • – What is the jobs mix that supports that community composition under different scenarios? What’s the job mix that minimizes commuting and associated GHG emissions? 
  • – What’s the mix of businesses, jobs and housing that move toward fiscal stability for the City in these scenarios? 
  • – Then in the end we arrive at a set of preferred growth rates that are appropriate for the scenarios that we’ve constructed. We can then develop our general plan to accommodate these preferred scenarios. 

My wife and I put forward one vision for Davis to focus on sustainable food development as an economic engine. I’m sure there’s other viable ideas. We need a forum that dives into these and formulates our economic plan rather than just bumbling along as we seem to be doing now. This is only likely to get worse with the fundamental changes after the pandemic.

I’ll go further to say that one of the roots of this problem is the increasing opaqueness of City decision making. “Playing it safe” is the byword for City planning, just when that’s what is most likely to hurt us. That’s why we proposed a fix to the fundamental way decisions are made by the City.

There’s a long list of poor decisions created by this opaqueness that shows how this has cost the City tens of millions of dollars. He points out symptoms of a much deeper problem that is impeding us from developing a long term vision.

It may seem like so much “inside baseball” to focus on the nuts and bolts of process, but its that process that is at the root of the crisis, as boring as that may seem.