Best Energy Companies in Wisconsin, United States
The 133 best Energy companies in Wisconsin, United States in 2026, ranked by funding and momentum. Funding, investors, founders, valuation, tech stack and live signals. Top: SHINE Technologies.
Our analysis of 171 Energy companies
$71.4b in tracked funding; 82% of the stack-profiled cohort runs cloud-native; funding activity peaked in 2025.
Ranked: Best Energy companies in Wisconsin
| # | Company | Last round | Disclosed funding | Employees | Founded | Founder | Patents & IP focus | Recent signals |
|---|---|---|---|---|---|---|---|---|
| 1 | a-c equipment services A-C Equipment Services is a manufacturer of rotary kilns and digesters. | — | — | 51 | — | — | 114 patents Continuous food processing equipment for cooking, cutting, coating, and patty formation | — |
| 2 | A. C. Engineering Provider of electrical testing and maintenance services | — | — | 1 | 1993 | — | 285 patents Patents concentrated in construction | — |
| 3 | ABL Lights Provider of lighting and electrical products | — | — | 70 | 1971 | Yves Henry Brepson ex-CEO & President | — | — |
| 4 | AES Provider of installation services of energy systems | — | — | 98 | 1978 | Steven Apfelbaum Founder & Chairman | 225 patents Automation and optimization of solar/wind energy installation, operation, and monitoring systems. | — |
| 5 | airsan Airsan designs and manufactures air filters. | — | — | 12 | 1941 | — | — | — |
| 6 | alps inspection ALPS Inspection provides leak test and inspection solutions. | — | — | 28 | 1974 | — | — | 2 launchs · 1 award |
| 7 | Alternate Energys Geothermal & solar heating system installer | — | — | — | 2004 | Rick McCutchin CEO & President | — | — |
| 8 | american transmission co We serve utilities that procure primary network transmission service. | — | — | 812 | 2001 | — | — | — |
Top 12 Energy companies in Wisconsin
#1
Series D · Janesville, Wisconsin · founded 2005 · 165 employees$413.6Mraised▾
Producer of nuclear isotopes using fusion techniques
- Feb 2026Series D$240M
- Oct 2024Grant (prize money)—
- Oct 2023Series C$70M
- Jul 2023Grant (prize money)$1.1M
#2
Series A · Middleton, Wisconsin · founded 2019 · 38 employees$82.5Mraised▾
Provider of fuel fusion energy services for healthcare, education, water, food, and transportation
- Jan 2026Series A$87M
- Nov 2024Seed—
- Jul 2024Seed$53.5M
- Mar 2023Seed$29M
#3
Series A · Madison, Wisconsin · founded 2021 · 5 employees$9Mraised▾
Developer of nuclear energy projects
- Feb 2026Conventional Debt$9.5M
- May 2025Series A$36M
- Dec 2024Seed—
- Jun 2023Grant (prize money)$3M
#4
Funding Raised · Pewaukee, Wisconsin · founded 2009 · 68 employees$113Mraised▾
SunVest Solar develops and installs solar PV projects on a residential and commercial scale. Claims to have installed 44k solar panels totalling to 13MW. Has a monitoring portal to monitor the installed systems. Installed a 21kW system for St. Dennis Church, a 158kW system for Madison Gas and Electric and others. Also develops community solar systems.
- Dec 2022Conventional Debt$113M
#5
Funding Raised · Milwaukee, Wisconsin · founded 2011 · 9 employees$716Kraised▾
Hydroponics solutions and resources for successful plant cultivation. We provide resources and information to empower individuals and businesses in the hydroponics industry. Our focus is on fostering successful plant cultivation through innovative techniques and readily available support. We offer a platform for users to connect, learn, and grow within the hydroponics community. We are committed to providing valuable content and resources to help our users achieve their hydroponic goals. We aim to be a trusted source for all things hydroponics, offering guidance and expertise to both beginners and experienced growers. We are dedicated to promoting sustainable and efficient plant cultivation practices through hydroponics.
- Jan 2025Grant (prize money)$75K
- Jul 2024Grant (prize money)$206.5K
- Dec 2022Grant (prize money)$75K
- Jun 2022Grant (prize money)$199.5K
#6
Public · Beaver Dam, Wisconsin · founded 2007$393Kraised▾
Provider of construction and infrastructure services. It offers a full range of services, from project planning and design to construction and management. The company also engages in public-private partnerships (PPP) for infrastructure development, providing investment and operational services throughout the project lifecycle. It has expertise in various sectors, including urban renewal and transformation. A significant portion of its business involves the development and management of large-scale infrastructure projects. The company's integrated approach ensures efficient project delivery and client satisfaction.
- Apr 2025Grant (prize money)$393K
#7
Series B · Madison, Wisconsin · founded 2005 · 118 employees$28.8Mraised▾
Neutron radiography and imaging solutions for aerospace, defense, and industrial sectors. They provide nondestructive testing services using neutron imaging, a technique that reveals the internal structure of components without damage. This is crucial for quality assurance, failure analysis, and research and development. They offer a reliable alternative to reactor-based facilities, providing high-resolution imaging with greater flexibility and reduced overhead. Their services support manufacturers in delivering safe, high-quality products across various industries. They are certified and compliant with industry standards, including AS9100D and ITAR, ensuring quality and security. They empower reliable, agile suppliers of safe, high-performing products.
- Mar 2020Series B$999.8K
- Dec 2018Series B$15M
- Oct 2017Series A$12M
- Oct 2017Series A$1.7M
#8
Public · Manitowoc, Wisconsin · founded 1996 · 231 employees$10.5Mraised▾
Provider of energy-efficient LED lighting solutions and EV charging services. This company designs, manufactures, and installs LED lighting systems for commercial and industrial spaces, offering retrofits, high bay and low bay lighting, and outdoor solutions. They also provide comprehensive maintenance and project management services. In addition, they offer design and installation services for commercial-grade EV charging stations, collaborating with clients to meet specific project needs. The company's focus is on reducing energy consumption and promoting sustainability for its clients.
#9
Acquired · Milwaukee, Wisconsin · founded 2010 · 37 employees$2.5Mraised▾
Gearbox Express develops down-tower, wind gearbox remanufacturing solutions. The company is a remanufacturer and GBXchange exchange inventory of gearboxes, its ancillary equipment, main shafts, and bearing. They also have a 3.1 MW regenerative test stand for simulating real world situations.
- Sep 2018Conventional Debt$5M
- Jul 2016Seed$450K
- Jul 2013Seed$200K
- Jun 2011Seed$1.8M
#10
Seed · Manitowoc, Wisconsin · founded 2012 · 13 employees$2.3Mraised▾
Distributed energy resource company specializing in LED, solar, controls, and IoT. Focused on developing and integrating award-winning, high-performance LED lighting solutions, off-grid solar-powered LED systems, advanced controls, and IoT devices. The mission is LED DONE RIGHT®, driving innovation and shaping the future of the illumination industry with bold designs and proprietary advancements. Continually researching and developing advanced methods for increasing quality illumination while reducing energy input and managing heat output to achieve new standards in component longevity. Designs prioritize the optimization of the light engine as a system that delivers maximum foot-candles without compromising performance or longevity.
- Feb 2015Seed$1.1M
- Nov 2013Seed$600K
#11
Funding Raised · Wauwatosa, Wisconsin · founded 2016 · 8 employees$898.2Kraised▾
Manufacturer of batteries
- Sep 2020Grant (prize money)$145.9K
- Sep 2018Grant (prize money)$752.2K
#12
Acquired · Scandinavia, Wisconsin · founded 2007 · 149 employees$200.5Kraised▾
Rototec provides geoenergy based heating and cooling for large properties. Our concept includes surveying, design, drilling and installation as well as consulting for geoenergy projects. Rototec group operates in Finland, Sweden and Norway.
- Jan 2023Grant (prize money)$200.5K
Funding & investor landscape
Notable founders
Market landscape — 10 sub-themes by coverage
Share of Energy coverage by sub-theme.
Regulatory-risk over time rising
Funding & growth over time
funding rising · growth rising
How research on Energy Storage in Wisconsin is moving
A read on the academic research around Energy Storage in Wisconsin — which themes are gaining ground, the institutions and researchers driving them, and how the tone is shifting. Based on 60 papers.
UW–Madison and UW–Milwaukee lead Wisconsin's optimistic energy-storage research, focusing predominantly on advanced battery technologies and microgrid optimization, with breakthroughs and advancements vastly outweighing concerns.
- University of Wisconsin–Madison37
- University of Wisconsin–Milwaukee12
- University of Wisconsin–Green Bay7
- University of Wisconsin–Superior1
- University of Wisconsin System1
- Electrochemistry1→6
- Battery (electricity)2→5
- Renewable energy2→5
- Distributed generation1→3
- Battery (electricity)3
- Renewable energy2
- Benchmarking1
- Robot1
- Strengths and weaknesses1
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.