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.
| Company | Batch | Team | 6 mo | 12 mo | Open roles | Total raised | Last round |
|---|---|---|---|---|---|---|---|
Building the world's first fusion power plant | S14 | 594 | +11% | +34% | 49 | $1.5B | Series G$500M, Jun 2026 |
Emission free, always on power from advanced fission power plants. | S14Public | 418 | +28% | +75% | 3 | $1.4B | Post-IPO equity$1B, Sep 2026 |
India's Largest EV charging network | S20 | 328 | +10% | +13% | 1 | $46.1M | Undisclosed round$18M, Feb 2026 |
Protecting the grid today, preparing the grid for tomorrow | W21 | 221 | +18% | +51% | 1 | $97.2M | Series B$55M, Nov 2025 |
Sunrun for the developing world | W15 | 158 | −1% | −2% | 0 | $78.8M | Debt$15M, Oct 2025 |
Oolu is one of the fastest growing off-grid solar firms in West Africa | S15Acquired | 138 | −1% | −2% | 0 | $14.7M | Debt$300K, Sep 2022 |
Energy Orchestration Platform | W21 | 64 | +3% | +2% | 1 | $17.2M | Series A$15M, Nov 2022 |
Enterprise software to quantify cost-effective decarbonization… | W20 | 63 | +2% | +9% | 0 | $36M | Undisclosed round$22M, Mar 2024 |
Mobile Energy Storage Technology | W21Inactive | 50 | −2% | −4% | 0 | $124M | Undisclosed round$11M, Jun 2023 |
We use solar and wind power to make zero net carbon electrofuels | W19 | 43 | +2% | +5% | 0 | $150K | Series B$150K, Sep 2021 |
A carbon MRV solution for energy and hard-to-abate sectors | S16 | 40 | −9% | −11% | 0 | $69.3M | Series B$43.1M, Mar 2022 |
Long range, wireless energy distribution that scales | S15 | 39 | +3% | −5% | YC | $39.1M | Grant$30M, Jun 2026 |
Engineering the future of chemistry for natural resource extraction | S22 | 27 | −4% | 0 | |||
Traceable AI for billion-dollar infrastructure. | W22 | 24 | +4% | +20% | 0 | $3.8M | Non-equity support$234K, Jun 2026 |
Low-cost, high-scale EV charging platform for apartments (and more). | S21 | 19 | +6% | +6% | 1 | $7.8M | Grant$3M, Feb 2026 |
Predictive battery management software for electrified fleets | S20 | 18 | −18% | −33% | 0 | $29M | Series A$17M, Dec 2024 |
Electricity price forecasts for energy storage, ev charging, etc. | W21Acquired | 17 | −6% | −6% | 0 | $1.7M | Equity crowdfunding$57K, May 2022 |
Nuclear-inspired cooling that turns wasted power into more AI compute | S21 | 16 | −6% | 0 | $3.5M | Undisclosed round$1.3M, Feb 2026 | |
We make the most compact nuclear reactors | X26 | 13 | +117% | 0 | $32.1M | Undisclosed round$620K, Sep 2026 | |
Simulation software used by leading battery and automotive companies | S24 | 12 | 0% | +20% | 0 | $500K | YC investment$500K, Sep 2024 |
Powering tomorrow's industrial revolution in space | F25 | 11 | 0 | $500K | YC investment$500K, Dec 2025 | ||
Manage energy cost & usage with AI for facility & sustainability teams | S23 | 10 | +11% | +11% | YC | $500K | YC investment$500K, Jan 2024 |
AI that operates power plants | F26 | 9 | 0 | $2M | Pre-seed (before YC)$2M, May 2026 | ||
Sunfolding builds next generation infrastructure for solar farms. By… | S17Inactive | 9 | +13% | +13% | 0 | $32.1M | Series B$32M, Oct 2019 |
Clean marine AI datacenters | F26 | 8 | 0% | −20% | 0 | $5.7M | Seed$1.7M, Oct 2026 |
The first AI-powered uranium discovery company | W26 | 8 | YC | $500K | YC investment$500K, Jan 2026 | ||
Software for enterprise energy procurement. | W26 | 8 | 0 | $500K | YC investment$500K, May 2026 | ||
Nuvola is transforming battery manufacturing, making EV batteries… | W17 | 8 | 0% | +33% | 0 | SeedJan 2018 | |
Smart electric & water meters as a service | S22 | 6 | +20% | +20% | 0 | $150K | Grant$150K, Nov 2022 |
NextDrop is the water marketplace for urban India. We connect water… | S17Inactive | 6 | 0% | 0% | 0 | $120K | YC investment$120K, Aug 2017 |
Self contained solar-powered AI inference modules: the NanoDC | F26 | 5 | 0 | Pre-seed (before YC)May 2026 | |||
Hyper-efficient coolers for data centers | X26 | 5 | 5 | ||||
Distributed energy infrastructure unlocking grid power to data centers | X25 | 5 | 0 | ||||
We build data centers 10x faster | S24 | 5 | 0% | −17% | 0 | $4.5M | Seed$4M, May 2025 |
Building a frontier world model for power | W23 | 5 | −29% | −17% | 0 | $500K | YC investment$500K, Jan 2024 |
Energy independent data centers with solar and repurposed batteries. | W26 | 4 | 0 | $500K | YC investment$500K, Jan 2026 | ||
AI agents for power grid planning 🦑 | W26 | 4 | 0 | $500K | YC investment$500K, Jul 2026 | ||
Predictive maintenance for power infrastructure. | F26 | 3 | 0 | ||||
AI-Native Engineering Firm designing Data Centers | S26 | 3 | 0 | ||||
Floating nuclear powered data centers at sea. | S26 | 3 | 0 | ||||
Batteries and solar for $0 upfront to help businesses save money | W24 | 3 | −40% | 0 | $1.5M | Pre-seed$983K, Apr 2024 | |
Building flying wind turbines. | S19 | 3 | 0 | $1.7M | Grant$1.6M, Sep 2025 | ||
Computer vision operating layer for physical infrastructure | F26 | 2 | 0 | ||||
Robots that run autonomous depots for autonomous fleets. | W26 | 2 | 0 | $500K | YC investment$500K, Apr 2026 | ||
Fusion reactors for ships | W25 | 2 | YC | $5M | Seed$4.5M, Nov 2025 | ||
First commodity marketplace for hydrogen. | W22Inactive | 2 | 0 | Pre-seedMar 2022 | |||
Reducing energy costs & emissions in buildings. | S21Acquired | 2 | 0 | $125K | YC investment$125K, Aug 2021 | ||
Nanoparticle tracers for reservoir characterization during hydraulic… | S16Inactive | 2 | 0 | $120K | YC investment$120K, Aug 2016 | ||
using ultrasonics + ml to analyze fluid behavior at infrastructure… | W16 | 2 | 0 | $6.6M | Undisclosed round$6.5M, Jan 2019 | ||
We deliver affordable renewable energy direct to customers and are… | W19Inactive | 1 | 0 | $150K | Debt$150K, May 2020 |
Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.
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.
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.
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.
# 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
60 Y Combinator companies are in Energy; 49 are active.
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.
By team growth over 6 months (10+ people): Apollo Atomics, Inc. (+117%), Oklo (+28%) and Gridware (+18%).
Largest latest rounds in the last 12 months, after their YC batch: Helion Energy ($500M), Gridware ($55M) and Statiq. ($18M).