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YC Energy companies

60 Y Combinator companies in Energy, with team size, growth, open roles and funding.

Updated weekly, last on November 9, 2026. Roster from Y Combinator's public directory.

Hiring the mostlast 60 days
49 roles
Helion EnergyS14
  1. 2Madrone5
  2. 3Oklo3
See all 7
Fastest growingteam, 6 months
+117%
Apollo Atomics, Inc.X26
  1. 2Oklo+28%
  2. 3Gridware+18%
See all 12
Shrinkingteam, 12 months
−33%
Zitara Technologies, Inc.S20
  1. 2Validere−11%
  2. 3Reach−5%
See all 5
Raised the mostlast 12 months
$500M
Helion EnergyS14
  1. 2Gridware$55M
  2. 3Statiq.$18M
See all 7
Companies
60
Active
49
Hiring, last 60 days
7
Open roles, 60 days
61
People on these teams
2,449
Showing 50 of 60 companies
CompanyBatchTeam6 mo12 moOpen rolesTotal raisedLast round
Building the world's first fusion power plant
S14594+11%+34%49$1.5BSeries G$500M, Jun 2026
Emission free, always on power from advanced fission power plants.
S14Public418+28%+75%3$1.4BPost-IPO equity$1B, Sep 2026
India's Largest EV charging network
S20328+10%+13%1$46.1MUndisclosed round$18M, Feb 2026
Protecting the grid today, preparing the grid for tomorrow
W21221+18%+51%1$97.2MSeries B$55M, Nov 2025
Sunrun for the developing world
W15158−1%−2%0$78.8MDebt$15M, Oct 2025
Oolu is one of the fastest growing off-grid solar firms in West Africa
S15Acquired138−1%−2%0$14.7MDebt$300K, Sep 2022
Energy Orchestration Platform
W2164+3%+2%1$17.2MSeries A$15M, Nov 2022
Enterprise software to quantify cost-effective decarbonization…
W2063+2%+9%0$36MUndisclosed round$22M, Mar 2024
Mobile Energy Storage Technology
W21Inactive50−2%−4%0$124MUndisclosed round$11M, Jun 2023
We use solar and wind power to make zero net carbon electrofuels
W1943+2%+5%0$150KSeries B$150K, Sep 2021
A carbon MRV solution for energy and hard-to-abate sectors
S1640−9%−11%0$69.3MSeries B$43.1M, Mar 2022
Long range, wireless energy distribution that scales
S1539+3%−5%YC$39.1MGrant$30M, Jun 2026
Engineering the future of chemistry for natural resource extraction
S2227 −4%0
Traceable AI for billion-dollar infrastructure.
W2224+4%+20%0$3.8MNon-equity support$234K, Jun 2026
Low-cost, high-scale EV charging platform for apartments (and more).
S2119+6%+6%1$7.8MGrant$3M, Feb 2026
Predictive battery management software for electrified fleets
S2018−18%−33%0$29MSeries A$17M, Dec 2024
Electricity price forecasts for energy storage, ev charging, etc.
W21Acquired17−6%−6%0$1.7MEquity crowdfunding$57K, May 2022
Nuclear-inspired cooling that turns wasted power into more AI compute
S2116−6% 0$3.5MUndisclosed round$1.3M, Feb 2026
We make the most compact nuclear reactors
X2613+117% 0$32.1MUndisclosed round$620K, Sep 2026
Simulation software used by leading battery and automotive companies
S24120%+20%0$500KYC investment$500K, Sep 2024
Powering tomorrow's industrial revolution in space
F2511  0$500KYC investment$500K, Dec 2025
Manage energy cost & usage with AI for facility & sustainability teams
S2310+11%+11%YC$500KYC investment$500K, Jan 2024
AI that operates power plants
F269  0$2MPre-seed (before YC)$2M, May 2026
Sunfolding builds next generation infrastructure for solar farms. By…
S17Inactive9+13%+13%0$32.1MSeries B$32M, Oct 2019
Clean marine AI datacenters
F2680%−20%0$5.7MSeed$1.7M, Oct 2026
The first AI-powered uranium discovery company
W268  YC$500KYC investment$500K, Jan 2026
Software for enterprise energy procurement.
W268  0$500KYC investment$500K, May 2026
Nuvola is transforming battery manufacturing, making EV batteries…
W1780%+33%0SeedJan 2018
Smart electric & water meters as a service
S226+20%+20%0$150KGrant$150K, Nov 2022
NextDrop is the water marketplace for urban India. We connect water…
S17Inactive60%0%0$120KYC investment$120K, Aug 2017
Self contained solar-powered AI inference modules: the NanoDC
F265  0Pre-seed (before YC)May 2026
Hyper-efficient coolers for data centers
X265  5
Distributed energy infrastructure unlocking grid power to data centers
X255  0
We build data centers 10x faster
S2450%−17%0$4.5MSeed$4M, May 2025
Building a frontier world model for power
W235−29%−17%0$500KYC investment$500K, Jan 2024
Energy independent data centers with solar and repurposed batteries.
W264  0$500KYC investment$500K, Jan 2026
AI agents for power grid planning 🦑
W264  0$500KYC investment$500K, Jul 2026
Predictive maintenance for power infrastructure.
F263  0
AI-Native Engineering Firm designing Data Centers
S263  0
Floating nuclear powered data centers at sea.
S263  0
Batteries and solar for $0 upfront to help businesses save money
W243 −40%0$1.5MPre-seed$983K, Apr 2024
Building flying wind turbines.
S193  0$1.7MGrant$1.6M, Sep 2025
Computer vision operating layer for physical infrastructure
F262  0
Robots that run autonomous depots for autonomous fleets.
W262  0$500KYC investment$500K, Apr 2026
Fusion reactors for ships
W252  YC$5MSeed$4.5M, Nov 2025
First commodity marketplace for hydrogen.
W22Inactive2  0Pre-seedMar 2022
Reducing energy costs & emissions in buildings.
S21Acquired2  0$125KYC investment$125K, Aug 2021
Nanoparticle tracers for reservoir characterization during hydraulic…
S16Inactive2  0$120KYC investment$120K, Aug 2016
using ultrasonics + ml to analyze fluid behavior at infrastructure…
W162  0$6.6MUndisclosed round$6.5M, Jan 2019
We deliver affordable renewable energy direct to customers and are…
W19Inactive1  0$150KDebt$150K, May 2020

How this works

1. The roster

Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.

2. The numbers

Each company is matched to Crustdata by its website. Crustdata adds team size and its change over 6 and 12 months, open roles from job postings, reported funding, and founders' past employers.

3. The lists

Hiring the most counts distinct roles posted in the last 60 days. Growth needs 10+ people today, shrinking 20+ a year ago, so tiny teams do not top the lists. Rebuilt every week.

Built with Crustdata. Get your own API key and build your own.

The numbers on this page come from three Crustdata API calls. Crustdata tags 5,000+ companies with Y Combinator as an investor; swap the filter for any investor, industry or headcount range and track your own list, with founders' work emails one call away.

  • Company search for team size, growth and funding
  • Job search with a count by company, for who is hiring and for what
  • A watch that re-runs the search weekly and sends only what changed
# 1. every company with Y Combinator as an investor
curl https://api.crustdata.com/company/search \
  -H "authorization: Bearer $CRUSTDATA_API_KEY" \
  -H "x-api-version: 2025-11-01" \
  -d '{
    "filters": { "field": "funding.investors",
                 "type": "in", "value": ["Y Combinator"] },
    "fields": ["basic_info.name",
      "headcount.total", "headcount.growth_percent",
      "funding.total_investment_usd"],
    "limit": 100
  }'

# 2. open listings per company, last 60 days (limit 0 = counts only)
curl https://api.crustdata.com/job/search \
  -H "authorization: Bearer $CRUSTDATA_API_KEY" \
  -H "x-api-version: 2025-11-01" \
  -d '{
  "filters": { "op": "and", "conditions": [
    { "field": "company.basic_info.company_id",
      "type": "in", "value": [...] },
    { "field": "metadata.date_added",
      "type": "=>", "value": "2026-08-24" } ]},
  "limit": 0,
  "aggregations": [{ "type": "group_by",
    "field": "company.basic_info.company_id", "agg": "count" }]
}'

# 3. the same company filter as a weekly watch: POST /watch/company/search

Questions about YC Energy companies

How many YC Energy companies are there?

60 Y Combinator companies are in Energy; 49 are active.

Which YC Energy companies are hiring?

7 companies posted roles in the last 60 days, led by Helion Energy (49 roles), Madrone (5 roles) and Oklo (3 roles). 7 mark themselves as hiring on YC's directory.

Which YC Energy companies are growing fastest?

By team growth over 6 months (10+ people): Apollo Atomics, Inc. (+117%), Oklo (+28%) and Gridware (+18%).

Which YC Energy companies raised the most?

Largest latest rounds in the last 12 months, after their YC batch: Helion Energy ($500M), Gridware ($55M) and Statiq. ($18M).

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