Sandbrook Capital

General contacts

Investor type

Founded

2021

AUM

$4 500 M

Location

Stamford, Connecticut, United States

Investment Ticket

$10-50 m

Investment Stage

Series B Late Stage (Series C+)

Region of investment

North America Europe

Investor profile last updated: 16 August, 2026

Profile

Sandbrook Capital is a private equity firm based in Stamford, Connecticut, founded in 2021 by Alfredo Marti. The firm specializes in building infrastructure companies that support reliable and lower-carbon power systems. With a team of 22 professionals, Sandbrook Capital focuses on creating impactful companies in the energy sector, leveraging decades of experience in climate infrastructure.

The firm invests primarily in climate infrastructure and energy sectors, with a focus on North America and Europe. Sandbrook Capital manages $4.5 billion in assets under management, including committed but uncalled capital. The firm targets investments in sectors such as battery storage, solar, wind, and pumped storage, supporting projects that contribute to a net-zero world.

Notable investments by Sandbrook Capital include NeXtWind - a German renewable energy company, rPlus Energies - a utility-scale renewable energy developer, Cloverleaf Infrastructure - a developer of data center sites, and United Utility Services - providing maintenance solutions for grid infrastructure. These investments highlight Sandbrook's commitment to transforming energy infrastructure globally.

Industry

CleanTech Energy Infrastructure Industrial

Sandbrook Capital Funds

Name	Type	Industry	Stage	Region	Size	AUM	Launch date
Sandbrook Climate Infrastructure Fund I	Fund of funds	Industrial Infrastructure Energy	Seed Series A Series B	North America	$5-10 m	$1500 M	December 2023

Contacts

Name

Title

Social Networks

Kenneth Ryan Co-Founder and Partner

Co-Founder and Partner

k•••@•••

Carl Williams Co-Founder and Partner

Co-Founder and Partner

c•••@•••

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Investment-team contacts for Sandbrook Capital — including verified work emails and LinkedIn profiles — are available to Private Equity List subscribers.
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Contacts sourced from the firm's website and LinkedIn, re-verified on a rolling cycle. Spot a stale contact, or none at all? Report it — we re-run that firm within 48h and get back to you.

FAQs about Sandbrook Capital

Is Sandbrook Capital a venture capital or private equity firm?

Sandbrook Capital is a private equity firm. It backs companies at Series B and Late Stage (Series C+), writing tickets of $10-50 m.

Where is Sandbrook Capital located?

Sandbrook Capital is located in Stamford, Connecticut, United States.

When was Sandbrook Capital founded?

Sandbrook Capital was founded in 2021.

What sectors and industries does Sandbrook Capital invest in?

Sandbrook Capital invests in companies and startups in CleanTech, Energy, Infrastructure, Industrial.

What is Sandbrook Capital geographical focus of investments?

Sandbrook Capital invests in companies and startups in North America, Europe.

At what stages of companies and startups does Sandbrook Capital typically invest in?

Sandbrook Capital invests in companies and startups at Series B, Late Stage (Series C+).

What is the usual amount of Sandbrook Capital investment?

Sandbrook Capital usually invests $10-50 m on average.

What is the amount of assets of under management (AUM) for Sandbrook Capital?

Sandbrook Capital has around $4 500m assets under management.

When was Sandbrook Capital last fund created?

Sandbrook Capital last fund was created/launched in 2023-12-10

What are the contacts of Sandbrook Capital?

Sandbrook Capital can be reached through its website sandbrook.com and its LinkedIn page. Its general enquiries address is [email protected]. Cold-mailing a general inbox rarely reaches a partner, so Private Equity List also lists the investment-team contacts for Sandbrook Capital — names, roles, verified work emails and LinkedIn profiles — available on a Pro plan from $129/month (see pricing). Contacts are sourced from the firm's website and LinkedIn and re-verified on a rolling cycle. Spot a stale contact, or none at all? Report it — we re-run that firm within 48h and get back to you.

Can I access Sandbrook Capital data via API or MCP?

Yes. Every field on this page — profile, funds, investment criteria, portfolio and investment-team contacts — is available programmatically through the Private Equity List REST API and MCP server, so AI assistants such as Claude and ChatGPT can query Sandbrook Capital directly instead of scraping this page. One subscription covers both the web app and machine access — see API & MCP.

When was the Sandbrook Capital profile last updated?

Private Equity List re-verifies investor profiles on a rolling cycle, pulling from the firm's own website and LinkedIn rather than a one-off import. This profile was last updated on 16 August, 2026. Something out of date here? Report it — we re-run that firm within 48h and get back to you.