Power transformers for America's AI build-out.
European-engineered power transformers up to 500 MVA and 420 kV, built to IEEE/ANSI standards, with reserved production slots for US utilities, EPCs and data center developers.
Speed to power
Our committed slot.
- Qualified second source next to your existing suppliers
- Custom design for your site, not a catalog unit
- Shipped via Port of Houston, supported locally
No transformer, no megawatts.
US data centers need power faster than the grid can deliver it. Power transformers are one of the longest-lead items between a utility line and the server rack, and that is where Kolektor Etra fits.
Utilities & transmission
Grid step-down and autotransformers for the substations that connect new data center load.
HV / EPC contractors
Specified, tested units delivered to your schedule and your substation design.
Developers with own substations
Owner-furnished main power transformers for gigawatt-scale campuses.
Engineered for your site, tested to your standard.
Every transformer is designed in-house in Ljubljana and adapted to IEEE C57 and utility-specific specifications.
Power transformers
Step-down, step-up and autotransformers with on-load or off-circuit tap changers. Low losses and low noise by design.
Special & industrial transformers
Custom units for industrial loads, renewables and storage, including generator step-up for wind, solar and BESS sites.
Offshore transformers
Power transformers designed for offshore substations, proven in harsh marine environments, including US offshore wind.
Lock in your transformer before the queue does.
The US faces an estimated 30% shortfall in power transformer supply. We set aside dedicated production capacity for US data center projects, so your delivery date is committed, not hoped for.
Share your project
Site, MW, voltage levels and target energization date.
Engineering review
Our engineers propose a design to your spec within days, not weeks.
Reserve the slot
A framework agreement holds your production slot for 2028–2029.
Build, test, ship
Live witnessed FAT, shipment via Port of Houston, on-site support.
Trusted by the grid operators of Europe. Already energized in the US.
Close to 3,000 transformers delivered across 40+ countries, including utility-scale wind and solar projects in the United States.
| Client / project | Location | Scope | Year |
|---|---|---|---|
| US UKA Green Power – wind & solar | Montana, Illinois and other US sites | 110 MVA, 138 / 34.5 kV power transformers | 2020–2022 |
| US Revolution Wind offshore substation | Rhode Island / Connecticut | Auxiliary transformer, 38.1 kV | 2023 |
| US Holman Blue Sky solar & wind | Illinois and other US sites | 30–110 MVA, 115–138 kV | 2020 |
| Data center substation – MVM OVIT, Göd Data Center | Hungary | 2 × 25 MVA, 126 kV | 2018 |
| Iberdrola group (ScottishPower, Iberdrola Distribution) | UK, Spain | 160+ transformers, up to 360 MVA / 275 kV | 2017–2025 |
| E.ON | Sweden, Germany | 175 transformers, up to 500 MVA / 415 kV | 2010–2025 |
| Vattenfall | Sweden, Germany, Netherlands | 120+ transformers, up to 250 MVA | 2010–2025 |
A European factory you can see into, with a team in Houston.
Open Factory
Join factory acceptance tests live online, take a virtual plant tour, or visit us in Ljubljana. Full IEEE C57 test reports with every unit.
Local team & service
Kolektor Etra USA in Houston, TX: sales engineering in your time zone, response within 24 hours, and a US field service partner for installation and warranty.
Built to last
Over 90 years of transformer engineering, boutique production and in-house R&D. Each unit is designed for its site, not pulled from a catalog.
"European-engineered power transformers. Reserved production slots. Delivered to US standards."
GOLD
Lower Scope 3 risk for your supply chain
Kolektor Etra ranks in the top 5% of companies assessed by EcoVadis worldwide, supporting hyperscaler and utility sustainability targets.
Tell us about your project.
We will get back to you within one business day with an engineering contact and indicative slot availability.
Kolektor Etra USA
Houston, Texas
[Office address]
[US phone number]
[US sales email]
Headquarters & factory
Kolektor Etra d.o.o.
Šlandrova ulica 10, 1231 Ljubljana, Slovenia (EU)