Ethan Miller, TXSES Research Associate – Policy and Government Affairs
One might think that after several years of recurrent issues with the stability of the electric grid, Texas would have established a standard system for valuing the cost of grid failures. Unfortunately, that is not the case. However, the Texas Solar Energy Society is proud to announce that it has begun the daunting task of estimating the cost of grid service interruptions to the Texas economy. Based on preliminary information from some municipal utilities, electric cooperatives, a handful of investor-owned utilities and generating retail electric providers, TXSES estimates service interruptions cost Texas at least $2B in losses in 2023. When complete, this data can be used to budget for grid reforms, save ratepayers money and increase grid reliability. To get an idea of what the final project will resemble, check out Local Solar for All’s The Economic Impact of Michigan’s Unreliable Power Grid.
TXSES calculates these costs using the Interruption Cost Estimate (ICE) calculator from Lawrence Berkeley Labs, Nexant, and the US Department of Energy. The ICE Calculator accounts for the direct costs of interruption (electricity that is generated that doesn’t hit the grid, etc.), as well as indirect costs based on FEMA formulas (cost of expired food, forgone work hours/business meetings, etc.). For the calculator to work properly, it needs measures of reliability like SAIDI (System Average Interruption Frequency Index); SAIFI (System Average Interruption Duration Index), and CAIDI (Customer Average Interruption Duration Index) scores, as well as customer counts, both residential and nonresidential. There is a maximum limit to the number of customers that can be run at one time using the calculator, so analysis has to be at a smaller scale. TXSES is using the scale of utilities (municipal utilities, co-ops, investor-owned utilities, and generating retail electric providers).
Currently, TXSES has acquired and compiled available data from the Energy Information Administration (EIA), the Public Utility Commission of Texas (PUCT), and Public Citizen. The EIA-861 forms report data from some municipal utilities and co-ops but the forms are limited in reporting on competitive markets. PUCT Dockets #54467 and #46735 provide SAIFI and SAIDI for some investor-owned utilities, but do not break down residential/nonresidential customer counts and are currently unusable. Public Citizen provides a list of all municipal utilities and co-ops in the state. While TXSES has neither complete data for the regulated nor unregulated markets, TXSES has a fuller view of data gaps within the regulated market. This is to say that while the current cost estimate is usable, it is far from complete and very likely a massive undervalue of full costs.
As TXSES continues working on this effort, be sure to follow along. Please reach out to Ethan Miller, at ethan@txses.org if you have any questions or are looking to get involved.
Sunnova’s goal is to be the source of clean, affordable, and reliable energy with a simple mission: To power energy independence so that homeowners and businesses have the freedom to live life uninterrupted®.
Founded in Houston, Texas in 2012, Sunnova started its journey to create a better energy service at a better price. Driven by the changing energy landscape, technology advancements, and demand for a cleaner, more sustainable future, we are proud to help pioneer the energy transition.
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We are looking for talented and motivated individuals who thrive in a fast-paced, continuous improvement environment and want to change the world of energy. We believe in excellence in customer service and strive to ensure every customer has a reliable and optimized solar system.
While some distributed solar systems can be ground-mounted or placed atop car ports, the vast majority of residential systems are placed atop a homeowner’s roof. As such, it’s helpful to know what changes, if any, need to be made to a roof before installation, and for replacement and upkeep down the road.
Pre-Installation Roof Repairs & Responsibility Before the installer goes about putting in an initial solar system, they should be able to let you know whether roof repairs are needed initially (roof replacement is usually recommended beforehand). Further, you should discuss with the installer whose job it is to repair damages to the roof or leaks.
Vent Pipe Placement Most roofs have plumbing vent pipes along them. Installers may simply work around them, but if you want to maximize your placement of panels, a roofer can be asked to either relocate vent pipes, or install low-profile vents which sit below panels.
6-Step ProcessADT Solar recommends following a sex-step process which involves 1. Notifying the system installer; 2. Have the system installer remove the solar panels; 3. Place the removed solar panels in an enclosed and protected area; 4. Have a roofer remove the damaged roof; 5. Have a roofer install a new roof; 6. Have the system installer reinstall the solar panels.
Identify Cost-Savings The DOE and NREL estimate that while in theory, the combined cost of roof replacement and solar installation should be $30,000, but that when performed together, the actual average cost was $25,000. The $5,000 in savings are possibly the result of partnerships between roofers and installers, essentially slashing the customer acquisition costs. Ask your roofer/installer about partnerships they have, which could result in savings of up to 30% on roofing.
Ethan Miller, TXSES Intern, and Larry Howe, Solar and Climate Solutions Advocate
It’s not hard to find estimates for utility-scale solar capacity in Texas; ERCOT regularly releases that information.1 What has been harder to find are estimates of distributed (rooftop) solar. Up until now, getting a realistic idea of how many buildings had rooftop systems was practically guesswork.
There are a few reasons for this:
Distributed solar can be metered or unmetered (and there are multiple metering techniques);
Distributed solar can be placed on residential, commercial and industrial buildings;
Reporting varies by utility provider (municipal, electric cooperative, competitive market, investor-owned); and
There is no singular reporting agency/organization.
Through the Texas Solar Energy Society, I connected with Larry Howe, who in his spare time was working on such an estimate. After meeting with him and reviewing his methodology and data sources, we devised a method to determine the volume of rooftop installations in the state.
For our analysis, we relied on scraping data from two main sources: the Electric Reliability Council of Texas (ERCOT) and the Energy Information Administration (EIA). For the latest numbers, we used ERCOT’s Load Profiling Profile Type Counts (last updated October 3, 2023), EIA’s Annual Electric Power Industry Report, Form EIA-861 (both for net-metered and non-net-metered, updated 2022 and 2021 for Austin Energy), and EIA’s Form EIA-861M (monthly, updated July 2023). [2][3][4]
Since ERCOT’s Load Profiles tracked the amount of distributed energy only in competitive (deregulated) regions of the state, we used the EIA-861 and EIA-861M to get installation counts for residential and commercial buildings in municipal and cooperative utilities. The biggest challenge, however, was that the EIA-861 only reported installation count for net-metered projects. The EIA-861M counts customers for residential and commercial. ERCOT had only an idea of how much MW capacity the non-net-metered generators were producing. To resolve this, I used Google’s Project Sunroof per roof system capacity of 12.3 kW DC.[5] It’s important to note that Project Sunroof is a tool designed to estimate maximum distributed capacity in the state. Because that 12.3 kW DC is a much larger system size than is typical, we believe our final estimate is likely conservative. Lastly, EIA data often included private utilities as well (those already reported in ERCOT numbers). We removed them to ensure we weren’t double-counting.
It’s important to disclose the limitations of our estimates.
As previously noted, we had to rely on Project Sunroof’s estimate of average project capacity. Additionally, not all data are dated for 2022. Because Austin Energy’s net-metered count didn’t appear in EIA’s 2022 data, (possibly because of the city’s use of Value-of-Solar in place of net-metering), we relied on data from 2021 which may be marginally outdated. Lastly, the data are incomplete. EIA doesn’t seem to report numbers for all municipal or cooperative utilities in the state, and ERCOT’s numbers are restricted to ERCOT’s area, so those serviced by the Western Electricity Coordinating Council, Southwest Power Pool, or Southeastern Electric Reliability Council have not been included.
With clean data, we tallied all the installations. As of today (October 19, 2023), we estimate the total number of rooftop solar installations in Texas to be ~294,817.86. To give a better idea of the scale, take the U.S. Census Bureau’s figure of 12,136,678 housing units in the state (as of 2022).[6] Using the numbers for residential installations only, it looks like 2.39% of all Texas residences have rooftop solar installed. For all buildings in the state, it is 2.31%. While that number might seem small, it’s impressive progress for a fledgling industry that didn’t even appear in the Solar Energy Industries Association count of annual solar installations until 2013.[7]
One decade in, we’ve made significant progress but there’s much more to do to enact sound distributed solar policies that will build a well-trained distributed solar energy workforce and mitigate impending grid disruptions and failures. Our newest initiative, Infinite Power: Take Your Share of the Texas Sun, is an ambitious statewide educational campaign intended to double the amount of distributed solar in Texas by 2030. Through a collaborative process with industry groups, business members, and solar homeowners alike, TXSES will lead that charge, intensifying consumer education and heightening awareness that distributed solar will support ambitious clean energy and carbon reduction goals, enhance the resilience and reliability of the electric grid and build a diverse, equitable, well-trained distributed solar workforce.
If you’re interested in getting involved with similar research or would like to access our data, please reach out to Ethan Miller (ethan@txses.org)
Sources:
“Annual Electric Power Industry Report, Form EIA-861 Detailed Data Files.” Electricity, 2022. https://www.eia.gov/electricity/data/eia861/.
“Estimated Rooftop Solar Potential of Texas.” Project Sunroof, June 2019. https://sunroof.withgoogle.com/data-explorer/place/ChIJSTKCCzZwQIYRPN4IGI8c6xY/.
“Profile Type Counts.” Load Profiling, October 3, 2023. https://www.ercot.com/mktinfo/loadprofile.
“Texas Solar.” Solar Energy Industries Association, 2023. https://www.seia.org/state-solar-policy/texas-solar.
“Texas.” QuickFacts, July 1, 2022. https://www.census.gov/quickfacts/fact/table/TX,US/EDU685221.
Vegas, Pablo, et al. “September 2023 Fact Sheet.” Electric Reliability Council of Texas, September 2023. https://www.ercot.com/files/docs/2022/02/08/ERCOT_Fact_Sheet.pdf.
If you are looking to install solar onto your home or business but feel overwhelmed at the number of installer options available to you, TXSES is here to help. We’ve put together a list of the top ten factors to consider when making the decision on which installer to go with.
1. Use a certified or accredited installer – The North American Board of Certified Energy Practitioners is one of the primary organizations tasked with issuing accreditation to solar installation businesses. In Texas, installers must be licensed through the Texas Department of Licensing and Regulation and be performed by licensed electricians.
2. Use a member or business of a trusted industry group – Groups like Texas Solar Energy Society and the Solar Energy Industries Association have their own vetting processes for ensuring the ethical operation and standard of service for installers. Industry groups represent a good first stop to find some installers, and TXSES even offers a map of installers by county.
3. Use an experienced installer – The DOE recommends installers have a minimum of three years’ experience. They should be able to answer any and all questions about solar that you have (how is installation performed, what panels are used, what is the generation capacity of the panels, etc.).
4. Check reviews and referrals – Personal networks and online reviews are excellent sources of weeding through installers. Personal connections may be able to give you insight into the quality of previous jobs, and online resources can help identify suspicious business practices.
5. Compare quotes and cost estimates – The DOE recommends using Berkeley Lab’s Tracking the Sun tool to get a rough estimate of the cost of solar installations, and a reasonable bid before contacting installers. You should compare at least two bids across multiple installers to get a reliable estimate. Additionally, your installer should be able to explain the source of each cost within the offer, and inform you of any legitimate tax credits or installation incentives available.
6. Clarify corporate chain-of-command – The installer should disclose whether they do the work in-house or subcontract out. If the installer subcontracts, get information on the subcontractor, their experience, accreditation, etc.
7. Ensure conduction of roof-check – The installer should perform an analysis of the roof conditions before proceeding with installation. Make sure that they do so, and whether or not they recommend roof repairs or roof adjustments and options available.
8. Ensure solar is the installers area-of-expertise – Just because a business does installation doesn’t mean it’s their bread and butter. Choosing a business that focuses on installation is almost a surefire way of ensuring the quality of the job is met.
9. Verify whether warranties or legal assurances exist – Installers should be transparent about performance and equipment warranties on the system. The Renewable Energy Design Group recommends 90% production over 10 years and 80% over 25 for performance warranties, and 10-12 years for equipment warranties.
10. Verify that the installer is a legitimate business – Unfortunately, solar scams are all too common, but we recommend checking with your local utility provider, and the Better Business Bureau’s Scam Tracker as two options to ensure the installers you’re looking at are not underhanded.
Barbose, Galen, Naim Darghouth, Sydney Forrester, and Eric O’Shaughnessy. “Tracking the Sun.” Berkeley Lab Electricity Markets & Policy. Accessed October 20, 2023.
