5 Solar Startups Transforming Global Power Systems

The Sun, the heart of our solar system, is a source of an enormous amount of energy.

This radiant energy, which is derived from the Sun’s light and heat, is known as solar energy. More importantly, it is the cleanest and most abundant source of energy, so much so that it can meet all our future energy needs.

Solar energy can be harnessed using a range of technologies. But there are two main ones: photovoltaics (PV), which convert sunlight directly into electricity through solar panels made of small solar cells, and concentrating solar power (CSP), which uses mirrors or lenses to focus sunlight to generate heat and then produce electricity.

Already, solar energy is contributing massively to the energy mix. In fact, solar helped clean power to account for more than 40% of global electricity in 2024. Meanwhile, new solar capacity installed was almost 600 GW.

New solar capacity installed globally reached 380 GW in the first half of 2025, an increase of 64% from 232 GW installed during the same period last year.

This rapid expansion makes solar the fastest-growing source of new electricity generation, which shows that the world is making a clear shift towards cleaner and more resilient energy systems. This growth, however, is not driven by just large-scale deployments but also innovative solutions developed by emerging companies.

So, let’s take a look at some of these prominent startups that are driving this progress. We chose these five based on technology differentiation, market impact, funding traction, and potential to scale solar adoption.

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1. Exowatt – P3 Solar-Thermal Power on Demand

The US-based Exowatt is building clean energy infrastructure, focusing on addressing solar intermittency through a simple, scalable design.

Its key offering is the “P3” system that provides power on demand by first capturing solar energy and then storing it in the form of heat, which is converted into electricity that can be dispatched as needed.

Each P3 unit is roughly the size of a shipping container and sits under a transparent canopy. Inside, lenses concentrate sunlight onto a heat-storage brick, and hot air is then routed to a separate enclosure that houses a Stirling engine and generator. This setup converts the stored heat into mechanical and then electrical power.

So, instead of going the traditional route of converting sunlight into electricity directly, Exowatt uses a thermal battery to store solar energy. This enables P3 modules to retain energy for up to 24 hours, and that too, at a fraction of the cost and space.

Hence, Exowatt can provide low-cost, reliable dispatchable energy without depending on the grid, which makes it perfect for remote or energy-constrained regions. The startup serves the energy-intensive needs of both commercial and government organizations.

The modular design of its flagship dispatchable solar product further enables the system to be deployed rapidly and scaled seamlessly.

To maximize performance and prevent any problems, Exowatt has created an intelligent energy ecosystem, where every module, system, and site is monitored, optimized, and automated 24/7 using advanced controls. A Digital Twin is also developed in collaboration with NVIDIA (NVDA +2.85%) and AWS for smart corrective actions and predictive maintenance.

All of these features make the renewable power system, P3, ideal for data centers and industrial users. In fact, Exowatt was designed to meet the fast-growing energy needs of AI and high-density compute environments and offers custom sizing for hyperscalers and edge computing.

Exowatt claims to have a commercial pipeline of over 90GWh of demand, mainly from data center operators and energy developers.

With the ongoing explosion of interest in AI fueling the massive demand for computer power, which has companies investing billions of dollars in infrastructure, Exowatt has also attracted the backing of major investors.

Last year, the energy startup secured a $20 million seed round from OpenAI’s Sam Altman and a16z. In April 2025, it followed with a $70 million Series A, and most recently, it closed a further $50 million extension, bringing total funding for this phase of growth to around $140 million.

The fresh funding would be utilized to expand the manufacturing and deployment of the P3 system.

Exowatt is actually only a couple of years old, co-founded in 2023 by CEO Hannan Happi and Chairman Jack Abraham.

“If Exowatt can deliver on its promise of delivering cheap solar power that generates electricity 24-7, it could upend the data center market and broader energy world,” said Happi in an interview with TechCrunch, revealing that the company already has a backlog of about 10 million P3 units. “The goal is to scale as fast as possible to the millions and ultimately billions of units,” he said.

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2. Enpal – Solar-as-a-Service for Households

The German greentech unicorn, Enpal, offers an integrated solution for renewable energy, aiming to make solar energy widely accessible and convenient to adopt. It is one of the fastest-growing residential solar providers in Europe.

“Previously, access to solar and heating was quite technical; it was entirely offline-based and decentralized. So we came up with a solution that’s entirely digital. We have created a seamless, customer-friendly user journey from sale to grid connection.”

– Enpal’s head of refinancing, Gregor Burkart, said in an interview

Enpal focuses on residential rooftop solar, storage, and EV chargers delivered via subscription. Its complete solar system package includes panels, battery storage, heat pumps, and wallboxes. One can either buy a solar system from Enpal or rent it under a flexible agreement, with installation services provided by qualified regional technicians. 

Founded in 2017, Enpal reached a valuation of $2.4 billion in 2023, after posting its first profit the year prior. Its revenue surpassed €900 million in 2023 before dropping to €860 million in 2024. In Q1 of this year, however, the company’s revenue per month picked up by 20% due to increasing demand for solar, “driven by very high household electricity demand.” Enpal’s customer count, meanwhile, has exceeded 90,000.

The German startup has raised a total of $655 million across 13 rounds, with its most recent funding round in April, when Enpal raised €110 million. “The round attracted strong investor demand and was significantly oversubscribed after just one week,” said the company in a statement.

With this fresh capital raise, Enpal is scaling its fast-growing smart metering and heat pump business, expanding its B2B platform Enpal.pro, and rolling out its Virtual Power Plant (VPP).

Recently, the startup also secured a second public debt deal backed by solar panels. Late last year, Enpal crossed €5 billion in asset financing commitments to enable the installation of its products. As a result, Enpal has installed more than half a million distributed energy resources (DERs), which are small-scale energy generation and storage systems, contributing 3 GW of energy to the grid.

With the help of this financing model, the startup is able to facilitate the broader adoption of renewable energy without having to rely on government subsidies.

Now, as part of the latest deal, a €700 million ($816 million) warehousing facility has been set up jointly with UK investment manager M&G to accelerate the roll-out of Enpal’s financing solution for residential solar and heating.

M&G will act as the key funding partner for Enpal as the provider of the loans to clients.

The facility is backed by €600m in senior lending from Barclays, Citi, Bank of America (BAC +0.74%), and Crédit Agricole CIB, which CFO and co-founder Viktor Wingert said, “highlights the appeal of our embedded financing model,” allowing the Germany’s largest heat pump provider to scale capital efficiently and bring “modern energy solutions to thousands of households without high upfront costs.”

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3. EcoFlow – Modular Fast-Charging LFP Solar Systems

Sequoia-backed EcoFlow is a Chinese company founded in 2017 by a group of battery engineers to accelerate the global transition towards renewable energy. Its focus is on portable solar systems, home backup solutions, and plug-and-play solar plus battery kits, which are all manufactured in its advanced Shenzhen facility with strict quality control.

The startup employs advanced technological solutions in its product development and possesses a portfolio of 1,129 patented technologies.

For instance, the use of LiFePO₄ (LFP) chemistry in many of its battery models gives it the benefit of high cycle life. Then there’s “X-Stream“ technology, which allows very fast recharge. In addition to advanced tech, EcoFlow offers the benefit of seamless scalability. Many of its systems are modular, so users can simply add extra batteries. On top of it, the startup offers smart features like AI forecasting and app connectivity to monitor, control, and optimize systems.

Packed with these capabilities, EcoFlow has expanded its operations all over the world and boasts five million-plus users globally. 

Recently, it entered the Australian home energy storage market with its Home Energy Ecosystem that combines the PowerOcean solar battery system with a range of connected devices, including the EcoFlow Smart Plug, PowerPulse 2 EV Charger, PowerHeat Air-to-Water Heat Pump, PowerGlow Smart Immersion Heater, and PowerInsight 2 Energy Monitor. All of these devices together offer a comprehensive and scalable home energy solution.

For a smoother expansion and a stronger position, EcoFlow secured strategic partnerships with local retailers, distributors, and solution providers. And this is how it has been able to successfully deliver smarter and more efficient energy systems across the globe.

Earlier this year, the Chinese unicorn launched its first permanently installed whole-home energy solution for the US market, the Ocean Pro system, which it claims is more powerful than any other system on the market, including Tesla‘s (TSLA +0.68%) Powerwall 3. It builds on the PowerOcean series that was launched in Europe a couple of years ago.

The Ocean Pro system features an Ocean Pro Inverter, which can handle eight batteries compared to just 3 for Tesla Powerwall 3, and supports solar arrays up to 40kW, double that of Tesla. The system also has a new Ocean Pro Battery with 10kWh of storage that’s expandable to 80kWh.

Ocean Pro can also be safely installed inside, having obtained UL 9540B safety certification approval. Additionally, it can operate in grid-tied mode, which means users can sell excess energy back to the power company. Meanwhile, the EcoFlow app can integrate with available VPP networks to help support the grid based on real-time conditions and prices.

With Felipe Burga of EcoFlow noting, “people want energy independence“ in the US, the startup is moving quickly to ride this wave of momentum with more accessible and resilient solutions.

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4. Yellow Door Energy – Zero-Capex Solar for Businesses

The UAE-based Yellow Door Energy operates in the Middle East and Africa, where it has deployed 400 megawatts of commercial and industrial solar projects. 

This number is set to increase to 500 MWp by the end of this year, thanks to signing four solar leases in the region. It has also started a solar project within Qatar and authorized nine more solar power projects in the UAE, Saudi Arabia, Bahrain, and Oman.

Just this month, the startup announced a partnership with Foulath Holding, the parent company of Bahrain Steel, to develop a 123 MWp solar project. It will involve the construction of the world’s largest single-site rooftop solar power plant, with 77,000 solar panels installed across a new 262,000-square-meter stockyard shed having a capacity of 50 MWp.

The site will have four ground-mounted solar photovoltaic (PV) installations and ten rooftop solar PV plants, which will help decarbonize the steel production in the Kingdom. In its first year of operation, the project aims to produce as much as 200 million kWh of clean energy annually.

Earlier this year, Abu Dhabi-based Emsteel also partnered with the renewable energy startup to finance, build, operate, and maintain a 31MW solar power project.

So far, in total, the startup has generated 1 billion kilowatt-hours (kWh) of clean energy through its solar projects, which has resulted in the prevention of 396,000 metric tons of carbon emissions.

Yellow Door Energy was founded a decade ago by Jeremy Crane, and in 2022, the startup raised $400 million in an equity investment to develop sustainable energy projects in the region and support countries’ net-zero emission targets.

It stands out for offering predictable, lower-cost clean energy to regions with high electricity prices and fast growth. The use of innovative solar leases or power purchase agreements (PPAs) enables businesses to transition to solar power and reduce their electricity costs without incurring any upfront capital expenditure.

Meanwhile, with investment in green energy intensifying all over the world, Yellow Door Energy stands to benefit significantly from this growth.

The UAE, in particular, is targeting almost 20 GW of clean energy capacity by 2030 and estimates as much as $55 billion in renewable infrastructure deployment. The nation boasts the largest installed solar capacity in the Middle East, reaching about 7.90 gigawatts in 2024. The UAE is targeting to generate 25% of its electricity from solar energy and achieve a total installed capacity of 44 GW by 2050.

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5. Epishine – Printed Organic Solar Cells for Indoor Light

Epishine is a Swedish energy company that aims to reduce electronic waste and contribute to a healthier planet by making cables, disposable batteries, and unnecessary maintenance obsolete.

To achieve this, it utilizes printed organic solar cells to capture indoor light to make electronics self-powered. These solar cells are manufactured using roll-to-roll printing that enables high-speed production with remarkable material efficiency. Employing this printing technique to manufacture organic solar cells allows the startup to produce thin and flexible formats that can seamlessly integrate into consumer devices.

Epishine’s solar cells are extremely thin, measuring slightly more than 0.2 mm. Also, they are mostly made up of PET material (polyethylene terephthalate), where just one gram of the active semiconductor material is enough for many square meters. These bifacial solar cells also enable the light to be captured from both sides, thus maximizing the energy output. For minimal environmental impact, it prioritizes maintaining low production temperatures.

This entire manufacturing process makes sure that Epishine’s solar cells are efficient and sustainable.

The startup offers two kinds of products: OneCell is for design-oriented customers, offering seamless integration into everyday products, while MultiCell ensures no losses in voltage conversion for higher efficiency.

Epishine solar cells that capture ambient light to power devices can be used in retail displays, remote controls, remote sensors, and asset trackers, eliminating the need for disposable batteries.

Its light-power technology was actually used in the new Google TV remote control.

“This collaboration marks an important milestone that shows how our light-power technology can support global leaders like Google in their sustainability journey. We are proud to see our solution enabling everyday electronics, reducing costs, simplifying design, and eliminating the use of disposable batteries.”

– CEO Anders Kottenauer

Recently, Epishine was awarded SEK 33.7 ($3.46 million) by the Swedish Energy Agency to accelerate the production of its printed solar cells. This will allow the startup to “meet the rapidly growing demand we see from customers globally.”

The grant was part of a larger funding initiative of SEK 240 million (almost $25.3 million) granted to nine local sustainable energy companies. 

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Conclusion: Why These Solar Startups Matter

As nations race to decarbonize amidst the surging electricity demand, which is driven by digitalization, electrification, and industrial expansion, solar power has emerged as a strong solution to meet these accelerating needs.

Solar energy has already established itself as one of the most critical pillars of the global clean-energy transition. With its abundance, declining costs, and versatility, solar represents a powerful solution to meet the soaring electricity demands while cutting carbon emissions at scale.

While supply-chain resilience, long-duration storage, recycling of solar components, increasing competition, and fragmented policies continue to present challenges, advances in materials science and technology can help solar become a self-optimizing power backbone for the planet, leading to a greener future.

Click here for a list of top solar stocks.