Monthly roundup · Cleantech · September 2026

Cleantech startup funding, September 2026: Simple Energy's $180M Series C leads 16 rounds

By Millionrounds ResearchPublished 1 October 2026Updated 25 October 2026

We read 16 equity rounds in Cleantech announced in September 2026, raising $850M between them: 4% of all the rounds we read that month and 2% of the money. The largest was Simple Energy's $180M Series C, led by Dr. Arokiaswamy Velumani Family Office. The median seed round was $4.3M, against $5.5M over the last twelve months across all sectors; at Series A it was $120M.

Equity rounds16in Cleantech, 15 with an amount
Raised$850Macross those rounds
Lead named100%of rounds say who led
Share of the month4%of rounds; 2% of the money

The biggest rounds

  1. 1Simple EnergySeries C · India · led by Dr. Arokiaswamy Velumani Family Office$180M
  2. 2HHertha MetalsSeries A · United States · led by Khosla Ventures, Doerr Capital$134M
  3. 3TARSeries A · United States · led by Spark Capital$120M
  4. 4AAMPIN Energy TransitionGrowth · India · led by Climate Investment Fund$100M
  5. 5Kanin EnergyGrowth · Canada · led by S2G Investments, Canada Growth Fund$100M
  6. 6Amber ElectricSeries E · Australia · led by 1GT, Morgan Stanley Investment Management's 1GT$56M
  7. 7Bluecore EnergySeed · United States · led by Silverton Partners$50M
  8. 8LightSeries A · United States · led by Matrix$46M
  9. 9Ultraviolette AutomotiveSeries E · India · led by TDK Ventures, Yali Capital$39M
  10. 10CCarrum MobilitySeries B · India · led by Alven$10M

Day by day

Equity rounds in Cleantech announced each day of September. The busiest day was 21 September, with 2.

1 September30 September

By stage, against the year

Each stage's median this month beside its twelve-month median: the sector's own where we hold enough rounds for a benchmark, otherwise the one across all sectors.

Seed7$4.3Mthis month$5.5M12 months, all sectors
Series A3$120Mthis month$20M12 months, all sectors
Series B1$10Mthis month$50M12 months, all sectors
Series C1$180Mthis month$100M12 months, all sectors
Growth2$100Mthis month$113M12 months, all sectors

Where

India had the most Cleantech rounds this month.

Against the month

  • Rounds, Cleantech16
  • Rounds, all sectors357
  • Raised, Cleantech$850M
  • Raised, all sectors$39B

The whole of September 2026

Other sectors in September

195 roundsAI→51 roundsFintech→39 roundsHealthcare→30 roundsBig Data & Analytics→27 roundsBiotech→25 roundsRobotics→24 roundsCybersecurity→23 roundsHardware & Electronics→22 roundsEnterprise Software→21 roundsSoftware→21 roundsEnergy→21 roundsConstruction→20 roundsHealthtech→20 roundsSaaS→19 roundsLogistics→17 roundsManufacturing→14 roundsAerospace & Space→14 roundsDefence Tech→13 roundsTelecoms→13 roundsSemiconductors→13 roundsClimate Tech→11 roundsAutomotive & EVs→10 roundsCloud→