Last Energy

Last Energy is a full-service developer of 20 MWe micro modular nuclear power plants.

Climate and energy Developer tools and cloud

Latest funding

$100M Series B+ · December 16, 2025

Led by Astera Institute · Source: techcrunch.com

Total raised: $143M across 3 sourced rounds

All 3 rounds ↓

Website: lastenergy.com.

X: @LastEnergy · 2,591 followers.

LinkedIn: lastenergy.

Categories: Climate and energy Developer tools and cloud.

Sectors: Clean Energy, Energy, Energy Management, Nuclear, Renewable Energy.

Stage: Series B+.

Based in: Washington, DC, United States.

Founded: 2020.

Total raised: $143M in 3 sourced rounds.

Last round: Dec 16, 2025 · 334 days ago.

Headcount: 51–100 employees.

On Recent Funding since: Sep 29, 2026.

Signals

X account@LastEnergy · created Jun 22, 2022 (4 years old) · 2,591 followers

Website registeredJan 16, 2011 (15 years old)

About Last Energy

By significantly reducing the time and cost of deployment, they are decarbonizing global energy production, increasing access to 24/7 baseload power, and creating a scalable clean energy future for humanity.

TIMELINE · MONEY RAISED

Last Energy | 2455 days on the record

@LastEnergy·Raised $143M in 3 sourced rounds

Money raised, round by round (amounts linked to their source). Pins are dated signals; hover the icons for dates.

Funding rounds

Date	Round	Amount	Lead	Source
Dec 16, 2025	Series B+	$100M	AAstera Institute	techcrunch.com
Aug 29, 2024	Series B+	$40M	GGigafund	canarymedia.com
Feb 25, 2020	Seed	$3M	FFirst Round Capital	venturebeat.com

Timeline

June 22, 2022
X account created
January 16, 2011
Website created

Founders and team

BK
Bret Kugelmass Founder

@bkugelma

Investors

Companies like Last Energy

EEavorSeries B+ · Jun 2025
TThe Nuclear Company$51M Series A · May 2025
AAslan RenewablesPre Seed · Nov 2025
AApplied Atomics$8.3M Seed · Mar 2026
GGeneral MatterSeries A · Apr 2025
VValar Atomics$1B Series B+ · Aug 2026

Other companies backed by Astera Institute

RRendezvous Robotics$20M Seed · Oct 2026
IImbue$200M Series B+ · Sep 2023

Astera Institute portfolio →

Sources and API

Every amount links to the page it came from. * Estimated from an accelerator's published standard deal, not a company-specific disclosure. How Recent Funding sources and verifies funding data. The same data as JSON: /api/v1/companies/last-energy (get a free API key).