Stri

What Stri does

STRI is an independent high-voltage testing laboratory headquartered in Ludvika, Sweden — within Sweden's "High Voltage Valley" and approximately 1.4 km from Hitachi Energy's Ludvika complex. Founded in 1990 and operating today as a division of Hitachi Energy Sweden AB, the company provides accredited type, pre-qualification, and development testing for power-system equipment including cables and accessories, breakers, HVDC valves, insulators and bushings, measuring transformers, GIS, surge arrestors, disconnectors, instrument transformers, and capacitors. STRI is SWEDAC-accredited under ISO/IEC 17025 and is a member of SATS and STL, ensuring that its test certificates are accepted across international mutual-recognition agreements (EA, ILAC, IAF).

The lab operates out of five electromagnetically shielded indoor test halls (the largest 25×37×30 m), a dedicated climate test hall with a 1500 kg/h steam generator, salt-fog and pollution-test capabilities, and outdoor testing areas. Maximum test ratings include 2800 kV lightning impulse, 1850 kV switching impulse, 1200 kV AC, 1600 kV DC, partial discharge and RIV up to 1200 kV, capacitance and tan δ to 1000 kV, and temperature-rise currents of 8000 A AC and 8400 A DC. STRI was the first laboratory in the world to perform 800 kV UHVDC testing (2008) and holds a one-million-volt UHVDC world record (2011); its climate test hall is described as one of the highest-performing in the world for pollution testing of 800 kV HVAC and HVDC equipment. The company also produces proprietary diagnostic instrumentation — including UV-sensitive imaging for discharge mechanisms and electric field probes for high-potential measurement developed in-house.

STRI runs a sales-led, inquiry-driven professional-services business. Customers contact the lab by phone (+46 240 795 00) or email ([email protected]) to request quotations; engagements are project-based contracts with electrical-equipment manufacturers and power-grid operators worldwide, executed at the Ludvika facility (with selected field testing internationally). Revenue is generated per test project rather than via subscriptions; pricing is quote-based and not publicly disclosed. Go-to-market is direct and minimal-marketing, relying on the website, SWEDAC/STL credentials, and the global reputation of being the first and among the highest-rated facilities for UHVDC and pollution testing.

Name

Stri

Legal name

Hitachi Energy Sweden AB (operating as STRI)

Website

https://stri.se

Company type

Private

Founded year

1990

Operating status

Operating

Headcount range

11–50 employees

Short description

STRI is an independent, SWEDAC-accredited high-voltage testing laboratory in Ludvika, Sweden (part of Hitachi Energy Sweden AB) that performs accredited type, pre-qualification, and environmental testing of power-system equipment up to 1100 kV for electrical-equipment manufacturers and power-grid operators worldwide.

Ownership category

akta.pro rank

Product category

High Voltage Testing Services

NAICS

Testing Laboratories and Services (541380), Testing Laboratories and Services (54138)

SIC

Services-Testing Laboratories (8734), Instruments For Meas & Testing Of Electricity & Elec Signals (3825)

akta.pro primary industry

Electrical Testing & Certification (Protection Relays, Switchgear, Transformers) (EUAEAHAG)

akta.pro secondary industries

Substation & HV Equipment Diagnostics (Partial Discharge, DGA, SF6) (EUAEAHAH), Commissioning, testing & energization services (HVT, relay testing, SAT) (EUADAKAE), Electrical Condition Monitoring (Partial Discharge, DGA, IR/Ultrasound) (EUAEAKAC)

Keywords

• High voltage testing
• Accredited test laboratory
• HVDC cable testing
• Type testing services
• Environmental testing

Headquarters

HQ city

Ludvika

HQ country

Sweden

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Infrastructure, Technology or R&D, Marketing or Sales

Revenue model

1. High Voltage Testing Services: STRI provides accredited testing services for high-voltage electrical equipment including cables, breakers, insulators, bushings, GIS, HVDC valves, and instrument transformers. Revenue is generated through project-based testing contracts with manufacturers and power grid companies.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels1 record

Core offering

STRI is an independent, SWEDAC-accredited high-voltage testing laboratory that performs accredited type testing, pre-qualification testing, and development testing for power system equipment including cables, breakers, HVDC valves, insulators, bushings, GIS, surge arrestors, disconnectors, instrument transformers, and capacitors. Testing covers system voltages up to 800 kV AC/DC and dielectric type tests up to 1100 kV, delivered through specialized test halls, climate chambers, and outdoor testing areas at the Ludvika, Sweden facility.

Product overview

STRI offers a comprehensive portfolio of high voltage testing services through its state-of-the-art laboratory facilities in Ludvika, Sweden. The company provides a single unified service offering focused on accredited testing of electrical equipment, including High Voltage Tests, Pollution and Environmental Testing, Cable Testing, Temperature Rise Tests, Tests at Multiple Stresses, Medium Voltage Testing, Pre-Qualification Tests of HVDC and HVAC Cables, Ion Migration Testing, Snow and Ice Testing, and Dielectric Type Tests of GIS Equipment. These services cover system voltages up to 800 kV (both AC and DC) and are designed for power grid companies and manufacturers of electrical equipment worldwide.

Differentiator

Problem solved

Functional benefit

Products and services

• High Voltage Tests Independent high voltage testing on power products with system voltages up to 800 kV, including dielectric tests and type testing on insulators, cables, bushings, breakers, GIS, surge arrestors, disconnectors, instrument transformers, capacitors, and HVDC valves.
• Pollution and Environmental Testing Climate test hall-based pollution and environmental testing of HVAC and HVDC equipment up to 800 kV, with maximum test voltage of 900 kV AC and ±1200 kV DC, using controllable sunlight, rain, humidity, heat, fog, and salt fog.
• Cable Testing Cable testing facilities for AC and DC transmission cable systems, including AC cable tests per IEC 60840 and IEC 62067, long-term heating cycle voltage tests, and electrical type tests for HVDC cables.
• Temperature Rise Tests Temperature rise testing with currents up to 8000 A AC and 8400 A DC to confirm products do not overheat during operation, performed on bushings, instrument transformers, disconnectors, and other equipment.
• Tests at Multiple Stresses AC and DC tests at multiple stresses per IEC TR 62730 with controllable environmental factors including sunlight, rain, humidity, heat, fog, and salt fog applied simultaneously to the equipment under test.
• Medium Voltage Testing Two test cells for medium voltage testing equipped with a 400 kV impulse generator and a 100 kV AC transformer, covering 100 m² for type tests on cables and cable accessories per IEC 60502.
• Pre-Qualification Test of HVDC and HVAC Cables Indoor test facilities for prequalification testing according to Cigré TB 496, IEC 60840, and IEC 62067, with maximum test voltages of 650 kV AC and 1050 kV DC for both indoor and underground cable systems.
• Ion Migration Testing Ion migration test facility to verify insulators can withstand 50 years in operation through varying temperatures, testing up to 50 insulators simultaneously per IEC 61325 clause 18.
• Snow and Ice Testing Climate test hall-based snow and ice testing of insulators, apparatus, and conductors, including combined pollution and ice tests on full-scale AC and DC equipment.
• Dielectric Type Test of GIS Equipment Dielectric type tests on Gas Insulated Switchgear (GIS) such as breakers, disconnectors, and busbars up to 1100 kV system voltage, including Test Duty 1, 2, and 3 per IEC 62271-102, with three-phase testing capability up to 420 kV system voltage.

Named customers2 records

Segments2 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature7 records

Partnerships

Four partnerships are on record, tiered core and minor.

• SATS (Scandinavian Association for Testing of Electric Power Equipment)coreStrategic or Co-development PartnerSTRI is a member of SATS, the Scandinavian Association for Testing of Electric Power Equipment, which is a member of the Short Circuit Testing Liaison (STL). All STL member laboratories are accredited and have equal status, ensuring internationally recognized test results.
• STL (Short Circuit Testing Liaison)coreStrategic or Co-development PartnerSTRI is a member of STL through SATS membership. STL is an international organization of independent and accredited high-voltage and high-power laboratories that agree on how to interpret standards, issue certificates, and calibrate equipment.
• CIGRE (International Council on Large Electric Systems)minorStrategic or Co-development PartnerSTRI cooperates with other international accredited laboratories via CIGRE, contributing to the writing of standards and sharing best practices in high-voltage testing.
• SWEDACcoreStrategic or Co-development PartnerSTRI is accredited by SWEDAC, the Swedish national accreditation body, in accordance with ISO/IEC 17025. SWEDAC is part of international agreements (EA, ILAC, IAF) ensuring mutual recognition of test results globally.

Scale indicators7 records

Recent moves10 records

Expansion highlights4 records

Broad incumbents

• SGS: World's largest TIC company with energy testing capabilities. Overlaps with STRI in HV component testing and certification as part of its diversified industrial services portfolio.
• Bureau Veritas: Global TIC conglomerate (industry, marine, infrastructure). Competes in HV equipment testing and certification as part of a broad industrial portfolio, with less specialization than STRI in UHVDC and pre-qualification.
• TÜV Rheinland: Global testing, inspection, and certification (TIC) company. Provides HV equipment testing and certification services alongside a much wider industrial and consumer testing portfolio, competing with STRI for type-testing work.
• Intertek: Global TIC provider with energy and electrical testing capabilities. Competes with STRI for HV product certification work while serving a much wider cross-industry testing customer base.
• DNV: Global energy testing, certification, and advisory firm with HV laboratory capabilities and IEC accreditation. Overlaps with STRI in HV equipment certification but operates a much broader portfolio spanning offshore, maritime, and energy advisory.
• TÜV SÜD: Global TIC company with energy and HV component testing services. Competes with STRI in cable and substation equipment certification while operating a much broader testing portfolio.

Direct peers

• KEMA Labs: Independent high-voltage and high-power testing laboratory (Arnhem, Netherlands; Chalfont, USA) with STL membership and IEC accreditation. Directly comparable to STRI in HV type testing, pre-qualification, and STL-issued certificates for cables, transformers, and switchgear.
• PowerTech Labs: Independent HV testing laboratory in Surrey, Canada, with STL membership. Competes with STRI for North American and global HV equipment qualification and pre-qualification testing work.
• CESI: Italian independent testing, certification and engineering center with HV laboratory capabilities and STL membership. Closest direct competitor to STRI for HVDC and HVAC equipment qualification testing in Europe.

Regional players

• IREQ (Hydro-Québec Research Institute): Utility-owned HV research and testing laboratory in Varennes, Canada. Directly comparable HV testing capabilities, including HVDC and FACTS, but primarily serves North American utilities and OEMs.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks5 records

Key highlights6 records

Customer concentration

Compliance2 records

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Stri