What they do:
Raptor Maps builds software to manage the solar PV lifecycle.
Quick facts:
HQ: Boston, MA, United States
Top Climate & Energy Startups in Massachusetts
This list has 13 startups and was last updated on Oct 15, 2026. Biggest hubs: Boston (6) and Cambridge (3). Largest teams: Raptor Maps, Gaiascope, and Brown Foods. Latest round: Adden Energy raised $16.9M (Oct 5, 2026).
13 startups
What they do:
Making 'REAL' Cow and Human Milk!
Quick facts:
HQ: Boston, MA, United States
What they do:
We make the most compact nuclear reactors
Quick facts:
HQ: Boston, MA, United States
YC X26Early stage
Quick facts:
HQ: Boston, MA, United States
Funding:
$180M · Equity · Apr 2026
Quick facts:
HQ: Cambridge, MA, United States
Funding:
$24M · Equity · Jan 2026
Quick facts:
HQ: Waltham, MA, United States
Funding:
$16.9M · Equity · Oct 2026
Quick facts:
HQ: Cambridge, MA, United States
Incorporated: 2024
Funding:
$14.6M · Equity · Mar 2026
Quick facts:
HQ: Charlestown, MA, United States
Incorporated: 2022
Funding:
$5.4M · Options · Feb 2026
Quick facts:
HQ: Cambridge, MA, United States
Incorporated: 2025
Funding:
$4.11M · Equity · Jan 2026
Quick facts:
HQ: Southborough, MA, United States
Incorporated: 2026
Funding:
$4.1M · Equity · Jun 2026
Quick facts:
HQ: Stow, MA, United States
Incorporated: 2023
Funding:
$759K · Debt · Oct 2026
Gaiascope
Acquired
What they do:
SaaS that helps renewables & energy storage operate more profitably
Quick facts:
HQ: Boston, MA, United States
CO2Stats
Shut down
What they do:
Social and environmental web analytics. Acquired in December 2016.
Quick facts:
HQ: Boston, MA, United States
YC S08Early stage
Questions and answers
How many startups are on this list?
There are 13 startups on this list, last updated on Oct 15, 2026.
Which of them are hiring?
None of them shows open roles right now.
Which of them have the largest teams?
By team size: Raptor Maps (75 employees), Gaiascope (9 employees), and Brown Foods (5 employees).
Which of them raised money recently?
Latest rounds: Adden Energy — $16.9M Equity (Oct 2026), River Otter Renewables — $759K Debt (Oct 2026), and Upstart Power Technologies — $4.1M Equity (Jun 2026).
Where are they based?
The biggest hubs are Boston (6) and Cambridge (3).