Best Solar Energy Companies in San Diego, United States
The 44 best Solar Energy companies in San Diego, United States in 2026, ranked by funding and momentum. Funding, investors, founders, valuation, tech stack and live signals. Top: OneRoof Energy.
Our analysis of 50 Solar Energy companies
$17.8b in tracked funding; 84% of the stack-profiled cohort runs cloud-native; funding activity peaked in 2025.
Ranked: Best Solar Energy companies in San Diego
| # | Company | Disclosed funding | Last round | Stage | Founder | Founded | Tech stack | Patents & IP focus | Recent signals |
|---|---|---|---|---|---|---|---|---|---|
| 1 | OneRoof Energy Offers residential rooftop services | $330M | 117 mo ago | Deadpooled | — | 2009 | — | — | — |
| 2 | PowerFlex Provider of renewable energy project development services | $100M | 44 mo ago | Acquired | — | 2017 | WebflowSalesforceAmazon Web Services+23 | — | — |
| 3 | Borrego Solar Solar EPC | $61M | 168 mo ago | Series C | Chris Anderson Co-Founder | 1980 | — | — | — |
| 4 | Pathway Power Developer of solar and wind energy projects 19Funding top 36%Talent bottom 49%Global bottom 36%Market bottom 20% All 4 signals ▾Fundingtop 36% Talentbottom 49% Globalbottom 36% Marketbottom 20% Funding: Raised $36.0M across 2 rounds · 2 rounds over 4 yrs (0.5/yr) Talent: 1 named leader on record · 1 C-suite/founder profile curated rank vs industry peers · Fliar Intelligence Index 19/100 | $36M | 21 mo ago | Series C | Jared Quient Founder and Managing Partner | 2022 | — | — | 2 partnerships |
| 5 | MCPV Manufacturer of heterojunction solar cells and modules for solar energy projects 24Talent bottom 49%Funding bottom 41%Global bottom 25% All 3 signals ▾Talentbottom 49% Fundingbottom 41% Globalbottom 25% Talent: 1 named leader on record · 1 C-suite/founder profile curated Funding: Raised $10.9M across 1 rounds · 1 rounds over 1 yrs (1.0/yr) rank vs industry peers · Fliar Intelligence Index 24/100 | $11M | 16 mo ago | Funding Raised | Marc Rechter Co-Founder & CEO | 2020 | — | — | — |
| 6 | Equal Earth Solar IPP company | $3M | 149 mo ago | Deadpooled | Andrew Duggan CEO | 2011 | — | — | — |
| 7 | Hyperlight Energy Solar fresnel and CSP technology developer | $2M | 147 mo ago | Series A | — | 2007 | — | — | — |
| 8 | Primo Energy Solar panel & products installation company | $2M | 83 mo ago | Seed | Hayden Van Zanten Co-Founder | 2012 | — | — | — |
| 9 | Luminia Commercial property solar & sustainability financing solutions | $1M | 82 mo ago | Seed | — | 2018 | WordPressMySQLPHP+34 | — | — |
| 10 | Powur Provider of solar energy services for homes | $1M | 124 mo ago | Seed | — | 2014 | WordPressApple iCloud MailGoogle Workspace+28 | — | — |
| 11 | focal point energy Focal Point Energy is the leading manufacturer of solar boilers for commercial and industrial customers in… | $954K | 165 mo ago | Deadpooled | — | 2007 | — | — | — |
| 12 | Icarus Thermal heat absorption and energy production solution for solar PV modules | $170K | 57 mo ago | Seed | — | 2016 | — | 11 patents Integrated solar PV‑thermal co‑generation with heat recovery, storage, and panel cooling systems | — |
| 13 | CollectiveSun Provider of solar financing and power agreements for nonprofits | $150K | 82 mo ago | Seed | — | 2011 | WordPressZohoMySQL+23 | — | — |
| 14 | PI Energy Developer of cost-disruptive, waferless solar photovoltaic materials for rooftop installations | $101K | 27 mo ago | Seed | Phil Layton Founder & CEO | 2007 | — | 1,199 patents Optimizing oil/gas extraction and uranium processing via fluid power, acoustic, and energy recovery technologies. | — |
Top 12 Solar Energy companies in San Diego
#1
Funding Raised · San Diego, California · founded 2020$10.9Mraised▾
Manufacturer of heterojunction solar cells and modules for solar energy projects. It focuses on advancing multi-gigawatt cell and module manufacturing. The company develops advanced manufacturing capacity of HJT cells and modules. It emphasizes sustainability in operations, dedicated to the recyclability and sustainable production of solar cells and modules. The company aims to accelerate innovation in the solar manufacturing landscape, combining technology improvements with industry partnerships and customer collaboration in product design and downstream solutions.
- Apr 2025Grant (prize money)$10.9M
#2
Series C · San Diego, California · founded 2022 · 10 employees$36Mraised▾
Developer of solar and wind energy projects
- Nov 2024Conventional Debt—
- Jan 2024Series C$25M
- Sep 2022Series C$36M
#3
Acquired · San Diego, California · founded 2017 · 300 employees$100Mraised▾
Provider of renewable energy project development services
- Dec 2022Series A$100M
- Sep 2018Grant (prize money)$744K
- Sep 2017Grant (prize money)$150K
- Jul 2017Grant (prize money)$225K
#4
Deadpooled · San Diego, California · founded 2009 · 33 employees$330.2Mraised▾
OneRoof Energy develops and distributes solar energy generation systems. The company also provides solar roofing systems installation and support services. OnRoof Energy has a strategic partnership with Eagle Roofing Products.
- Nov 2016Post IPO$17M
- Jun 2016Venture Debt$50M
- Mar 2016Post IPO$20M
- Dec 2015Venture Debt$20M
#5
Series C · San Diego, California · founded 1980 · 302 employees$61.4Mraised▾
Borrego Solar Systems specializes in commercial, residential and public sector turnkey, grid connected solar electric systems. The company has a portfolio of over 1100 solar PV projects and has offices in california, massachusetts and New York, and provides installation and services the USA.
- Aug 2012Series C$17.4M
- Feb 2012Conventional Debt$47M
- Aug 2009Series B$30M
- Feb 2009Series A$14M
#6
Seed · San Diego, California · founded 2007 · 5 employees$101.2Kraised▾
Developer of cost-disruptive, waferless solar photovoltaic materials for rooftop installations. The company focuses on fabricating and improving solar photovoltaic materials. Their technology aims to provide solar PV without government subsidies, avoiding traditional silicon wafer-based manufacturing. After internal testing, the patented technology will undergo third-party testing. This testing is a milestone in their commercialization plan. The company intends to share performance data and production costs with partners and customers. They also plan to establish manufacturing facilities using locally-sourced materials and explore fabrication opportunities. Initial sales will target companies requesting solar modules for large-area rooftop installations.
- Apr 2024Seed$720K
- May 2023Seed$349.9K
- Aug 2022Seed$51.2K
- Jul 2014Grant (prize money)$180K
#7
Deadpooled · San Diego, California · founded 2011 · 11 employees$2.6Mraised▾
Equal Earth owns and operates solar facilities in US and provides renewable energy for commercial and residential use. Equal has acquired LED Enviroworks, Kolona Painting & Construction and FOPCO,
- Mar 2014Seed$379K
- Oct 2013Seed$1.3M
- May 2013Seed$905K
#8
Seed · San Diego, California · founded 2012 · 8 employees$1.6Mraised▾
Manufacturer of off-grid micro-hybrid wind, solar, and battery platforms intended to revolutionize renewable energy technology. The company's turbines have patented blade and rotor designs that are combined with modified generators to deliver power, enabling users to have renewable and hybrid wind, solar, and battery storage products.
- Sep 2019Seed$1.6M
#9
Series A · San Diego, California · founded 2007$2Mraised▾
Hyperlight Energy designs, develops and manufactures concentrated solar thermal products like fresnel, which is used to generate steam which in turn generates electricity. The company has also patented linear Fresnel reflector technology under the brand "Hyperlight solar" a steam generator which has a conversion efficiency of around 40%.
- May 2014Series A$2M
- Aug 2011Seed$20K
#10
Seed · San Diego, California · founded 2018 · 23 employees$1.2Mraised▾
Commercial property solar & sustainability financing solutions
- Oct 2019Seed$1.2M
#11
Seed · San Diego, California · founded 2014 · 127 employees$1.2Mraised▾
Provider of solar energy services for homes
- Apr 2016Angel$1.1M
- Apr 2015Seed$75K
#12
Seed · San Diego, California · founded 2016 · 10 employees$170Kraised▾
IcarusRT has developed a heat absorption and energy production solution for solar PV modules. The offered product collects rejected heat from the PV panels and converts into additional power. The heat is also stored to generate power during peak demand and shady weather conditions.
- Nov 2021Seed$100K
- Jun 2017Seed$70K
Funding & investor landscape
Notable founders
Market landscape — 10 sub-themes by coverage
Share of Solar Energy coverage by sub-theme.
Regulatory-risk over time rising
Funding & growth over time
funding rising · growth rising
How research on Solar Photovoltaics is moving in the United States
A read on the academic research around Solar Photovoltaics — which themes are gaining ground, the institutions and researchers driving them, and how the tone is shifting. Based on 4,925 United States-affiliated papers.
- National Laboratory of the Rockies258
- National Renewable Energy Laboratory143
- Stanford University111
- Massachusetts Institute of Technology99
- Purdue University West Lafayette97
- Photovoltaic system44→239
- Solar energy26→202
- Renewable energy11→117
- Perovskite (structure)34→124
- Solar cell87→133
- Solar energy32→595
- Photovoltaic system72→593
- Renewable energy13→383
- Solar cell113→259
- Thermal3→116
- Solar energy16→204
- Photovoltaic system22→151
- Renewable energy11→126
- Solar power1→36
- Perovskite (structure)10→43
Where solar pv is researched across United States
Location clusters by institution affiliation — each city's volume, stance tone, and a quick read on its hot topic, what's advancing, the opening opportunity, and the main concern.
Who's filing solar pv patents in the United States
United States solar pv patent filing is cooling — 38,279 filings from 8,000 assignees (2016–2025), led by Sunpower, IBM, DU PONT; annual filings 4713→2618.
- Sunpower2948
- IBM2063
- DU PONT1694
- General Electric1511
- Universal Display1493
- Applied Materials1230
- First Solar1191
- 3M Innovative Properties920
Common questions
Riya reads income statements for fun. She covers the real money in a sector — revenue, growth, who actually earns — and never met a vague claim she didn't want a number for.