Energy Startups

RenSource develops, finances and manages solar and hybrid energy systems for commercial and industrial businesses, including universities, hospitals and industrial facilities. It provides energy infrastructure, financing and asset management across Africa, with Nigeria as its largest operational market.

1 investor

RenuLogix provides engineering, procurement, construction, and project management services for solar, storage, and EV charging infrastructure projects. The company serves developers and operators seeking reliable project delivery backed by technical expertise and customer service.

1 investor

Renuvi develops a long duration energy storage system based on its proprietary Salt-Matrix sodium-based battery electrochemistry, aimed at providing reliable clean energy for the power grid. The company positions its technology as a manufacturable battery with higher energy density than other sodium-based designs.

1 investor

RePG develops deep-tech energy and water systems that generate electricity, heating, cooling, and drinking water from air humidity and low-grade waste or geothermal heat (55-200°C). Its modular, off-grid, zero-emission devices serve industry, geothermal sites, homes, hotels, vehicles, data centers, and agriculture.

1 investor

iQueue is a software platform for searching the U.S. interconnection queue, benchmarking renewable energy projects, and building acquisition shortlists based on custom criteria. It serves renewable energy M&A and developer teams by turning fragmented queue, land, permitting, and ownership data into project viability assessments for diligence and deal sourcing.

1 investor

Repower is a Swiss energy utility that supplies electricity to households and manages the power grid, offering customers services such as billing, product selection, and reporting of relocations and outages. It operates power generation assets including solar installations like Madrisa Solar.

1 investor

RePowered Batteries evaluates surplus, end-of-life, RMA, and recalled battery inventory (post-consumer, industrial, and EV) to determine remaining value and repurpose batteries into new applications. It connects buyers, sellers, and partners across the battery supply chain and manages compliant recycling and disposal for businesses at every stage of the battery lifecycle.

1 investor

Repsol is a multi-energy company that produces and supplies energy, and works on the energy transition through initiatives run by its foundation. The page references quarterly financial results, press releases, and social initiatives combining innovation and technology.

1 investor

RePurpose Energy converts retired electric-vehicle batteries into "second-life" energy storage systems through battery testing, reassembly, and controls technology. Founded in 2018 to commercialize research from UC Davis, the company operates battery testing and reassembly facilities in the United States.

1 investor

REPWR is an Indigenous-owned clean technology company that designs and manufactures modular, high-efficiency solar systems for ISO shipping containers and intermodal freight, enabling ships, trains, and trucks to run on solar power. It also provides resilient solar-based power for islanded microgrids serving the port, mining, and defense sectors.</parameter> <parameter name="founders">[{"full_name": "Zachary A. McCue", "title": "Founder"}]

1 investor

RESA Power provides electrical services and support across the United States and Canada, serving renewables companies focused on sustainability and commercial establishments seeking operational efficiency.

1 investor

Resalta provides decarbonization-as-a-service in Central and Eastern Europe, offering fully funded energy efficiency and renewable energy projects to commercial, industrial, and public sector customers. The company designs and implements solar installations, heating and cooling systems, and building retrofit programs without requiring upfront capital from clients.

1 investor

Reservoir Group provides services and solutions for drilling, completions, and production operations to exploration and production operators and service companies. The company specializes in coring technology, drilling tools, well monitoring systems, and well intervention solutions across onshore and offshore environments.

1 investor

Reset provides environmental consulting services, including research, analysis, diagnosis, and information provision on environmental regulations covering waste, chemical substances, water quality, and environmental management. It also supports solar power and waste module recycling businesses through registration, licensing, and feasibility analysis.

1 investor

ResFrac develops a fully coupled hydraulic fracturing and reservoir simulator, providing physics-based simulation software and consulting services for oil and gas operators to optimize well spacing, completion design, enhanced oil recovery, and geothermal systems. It serves the North American shale industry, from small independents to supermajors and national oil companies.

1 investor

Reshape Energy provides energy solutions to real estate investors, including photovoltaic systems, battery storage, heating, cooling, and energy management across the project lifecycle. The company offers consulting, financing structures, technology integration, and long-term operation and maintenance services.

1 investor

Resilience installs and owns rooftop solar and battery storage on American homes at no cost to the homeowner, then aggregates these distributed systems into a virtual power plant that connects to energy markets and supports the grid. The company aims to lower electricity bills for working families while providing backup power and selling clean local capacity to communities.

1 investor

ResourceCo recovers and re-manufactures primary resources, extracting value from materials that would otherwise go to landfill. It works with governments, communities, and multinational companies to advance the circular economy and preserve natural resources.

1 investor

Reswitch provides a platform for Australian communities to access tangible benefits from nearby energy infrastructure projects such as wind and solar farms. The platform manages community benefit programs including electricity rebates, payments to landholders, and deployment of renewable energy and connectivity solutions.

1 investor

Resynergi converts plastic waste into recycled oil (PyOil) intended to achieve cost parity with conventional crude oil for use in plastics production. The company targets plastic recyclers, manufacturers, and communities seeking economically viable alternatives to virgin fossil fuels.

1 investor

retoflow offers a digital platform for planning electricity and pipe networks, built on the open-source tools pandapower and pandapipes, that connects data from GIS, ERP and metering systems into a central, computable network model for simulation and analysis. It serves utilities, grid operators and engineering firms working on energy transition challenges, and was founded in 2021 as a spin-off of Fraunhofer IEE and the University of Kassel in Germany.

1 investor

Return operates battery storage systems across Europe that stabilize power grids and integrate renewable energy sources. The company serves grid operators, energy producers, and businesses seeking reliable green electricity infrastructure.

1 investor

Return Carbon is a venture builder and investor focused on accelerating the transition to net-zero energy systems. The company works with startups and projects in the energy transition and climate sectors.

1 investor

RevaTerra is an advanced materials company that engineers forestry and agricultural residuals into high-density biomass fuel for energy and industrial markets. Its AI-powered bioenergy platform converts secondary biomass into dispatchable, lower-carbon power intended for high-load operations such as data centers.

1 investor