What STOLL Group does

STOLL Gruppe GmbH is a privately held, owner-managed German engineering services and project solutions provider founded around 1960, headquartered in Martinszell, Allgäu, and operating across Germany, Switzerland, and China with approximately 240 employees and 16 apprentices. The company delivers integrated project solutions across four end markets: energy technology, building technology, automation, and plant construction, organized through cross-functional Competence Centers for Engineering (CCE), Automation (CCA), and Operations (CCO), plus a Solutions (SOL) function and an agile PM@STOLL project management layer using JIRA and Wiki.

Customer-facing delivery is split between two sub-brands: FREY Engineering, which provides consulting, design planning, execution planning, and construction supervision, and STOLL Solutions, which handles plant construction, switchgear and control-cabinet manufacturing, PLC programming and commissioning, and the FREY/Stoll turnkey automotive test facilities (washing, leak testing, water treatment). Customers are enterprise B2B buyers in automotive, data centers, energy, food and beverage, and building/facility management, with named reference projects including bk solar's 4,000 kW Solarpark Jengen transfer stations.

The business model combines professional services revenue (engineering, project management, service and maintenance) with hardware revenue (transformer stations, switchgear, control cabinets, conveyor and test systems). Pricing is custom and project-scoped on multi-year contracts; no standardized tiers are disclosed. The company is bootstrapped with no external funding rounds identified, is family-owned across the Stoll and Rehm families, and operates under managing directors Sylvia Rehm, Stefan Stoll, Andreas Rehm, Michael Mildner, and Markus Stoll. Recent strategic emphasis has been on internal digital tooling (Charge@home EV charging concept, web-based engineering data editor, Microsoft Power Platform digitization) and on automated project-generation workflows to mitigate a tight automation-engineer labor market.

Name

STOLL Group

Legal name

STOLL Gruppe GmbH

Website

https://stoll-gruppe.com

Company type

Private

Founded year

1960

Operating status

Operating

Headcount range

101–250 employees

Short description

STOLL Gruppe GmbH is a family-owned German engineering and project solutions provider (~240 employees) delivering integrated electrical, automation, energy, and plant construction projects across automotive, data centers, energy, food and beverage, and building sectors in Germany, Switzerland, and China.

Ownership category

akta.pro rank

Product category

Industrial Electrical Engineering Services

NAICS

Engineering Services (541330), Engineering Services (54133), Architectural, Engineering, and Related Services (5413)

SIC

Services-Engineering Services (8711), Electrical Industrial Apparatus (3620), Industrial Instruments For Measurement, Display, And Control (3823)

akta.pro primary industry

Electrical Balance-of-Plant EPC (MV Collection, Cabling, Earthing, Lighting) (EUAEADAB)

akta.pro secondary industries

Construction Management & General Contracting (EPCM, Scheduling, QA/QC, HSE) (EUAMAFAJ), Solar Balance-of-Plant EPC (Piles/Foundations, Trenching, Combiner Networks) (EUAEADAJ), Balance-of-Plant (BOP) & Civil Works for Power Plants (EUAEAAAL)

Keywords

• Electrical engineering services
• Industrial automation solutions
• Energy technology systems
• Plant construction services
• Control cabinet manufacturing

Headquarters

HQ city

Martinszell

HQ country

Germany

HQ region

Europe

Offices5 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Supply Chain, Technology or R&D, Marketing or Sales, Infrastructure

Revenue model

1. Engineering and Project Services: Complete project solutions including consulting, planning, engineering, and construction supervision for energy technology, building technology, automation, and plant engineering. Revenue generated through project-based contracts with industrial and commercial customers.
2. Manufacturing and Assembly: Production of electrical installations, switchgear, control systems, and complete automation solutions. Manufacturing includes transformer stations, switching stations, conveyor systems, and testing facilities.
3. Maintenance and Service: Ongoing support, service, and maintenance for installed systems and facilities - providing recurring service revenue

Pricing tiers

Go-to-market motion1 record

Distribution channels1 record

Marketing channels8 records

Core offering

STOLL Group plans, manufactures, delivers, and supports integrated project solutions for electrical engineering and plant construction. Operating through two brands — FREY Engineering (consulting, planning, and construction supervision) and STOLL Solutions (execution, plant construction, switchgear and control cabinet manufacturing) — the company delivers full-lifecycle energy technology, building technology, and industrial automation solutions across automotive, data centers, energy, food & beverage, and facility management sectors.

Product overview

STOLL Gruppe is an owner-managed family business serving as an umbrella brand with approximately 240 employees operating in Germany, Switzerland, and China. The company operates two customer-facing brands: FREY Engineering (engineering services including consulting, planning, and construction supervision) and STOLL Solutions (plant construction and execution including test plants for automotive quality assurance, energy technology, building technology, and automation). FREY Engineering handles the design and planning phase while STOLL Solutions handles execution, enabling seamless project delivery from concept to completion. The company also develops proprietary software for automation using microservices and modern web frameworks.

Differentiator

Problem solved

Functional benefit

Brands

• FREY Engineering: Engineering services brand offering consulting, planning, and construction supervision for electrical energy supply, building equipment, and automation solutions
• STOLL Solutions

Products and services

• Engineering Services (FREY Engineering) Full-range engineering services including design planning, execution planning, consulting and feasibility studies, and construction supervision delivered as a single-source offering without risky interfaces, for industrial and commercial customers in energy, building, and automation projects.
• Energy Technology Solutions Planning, realization and support of electrical energy supplies including transformer stations, switchgear construction, emergency power systems, busbar systems, network planning and infrastructure, energy automation, and energy technology services.
• Building Technology Solutions Planning, realization and support of electrical building installations including low-voltage systems, lighting systems, IT and data technology, security technology, building automation, and facility management.
• Industrial Automation Solutions Complex machine and plant automation including electrical design, PLC programming and commissioning, and electrical assembly with scalable solutions and cost-optimized project approaches for industrial customers.
• Plant Construction - Test Plants Turnkey test plants for quality assurance in the automotive industry including fully integrated washing, leak testing, and water treatment systems, plus conveyor technology and plant automation.
• Switchgear Construction and Control Cabinet Manufacturing Electrical construction, control cabinet production, and electrical assembly services producing transformer stations, switching stations, conveyor systems, and complete automation solutions.

Quantifiable outcome

• Successfully delivered 230+ ongoing projects across multiple industries
• +2 more outcomes

Named customers5 records

Segments5 records

Ideal customer profiles5 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration10 records

AI capability2 records

Feature5 records

Partnerships

Six partnerships are on record, tiered minor and core.

• VDI (Verein Deutscher Ingenieure)minorStrategic or Co-development PartnerCollaboration on youth technical education through Arduino workshops hosted at STOLL facilities. VDI Zukunftspiloten program conducted workshops introducing programming and electronics to young participants.
• IHK SchwabencoreOthersIndustry and Commerce Chamber Schwaben recognized STOLL's 65-year company anniversary with an honorary certificate. Björn Athmer, Regional Director of IHK Schwaben, presented the award to Sylvia Rehm and Markus Stoll.
• WEITBLICK GmbHcoreOthersFormer Bayrhof Stoll GmbH, now operating as independent WEITBLICK GmbH with offices in Immenstadt. Continues to provide administrative services including Finance, Controlling, P&O, IT and Purchasing to STOLL Group. STOLL Group now handles these functions internally.
• bk solarminorStrategic or Co-development PartnerSTOLL delivered turnkey transfer stations for bk solar's PV ground-mounted system at Solarpark Jengen with 4,000 kW total capacity. Reference project demonstrating expertise in renewable energy infrastructure.
• SiemensminorStrategic or Co-development PartnerMichael Mildner, Head of Competence Center Automation, participated in an info talk at SPS trade fair showcasing how large projects can be successfully implemented using automated project generation despite limited automation technicians.
• Frey Engineering (Brand)coreOthersEngineering brand within STOLL Group providing consulting, planning, and construction supervision services. Seamless transition from Frey Engineering planning to Stoll Solutions execution.

Scale indicators6 records

Recent moves7 records

Expansion highlights5 records

Broad incumbents

• Schneider Electric: Global energy management and automation incumbent whose products STOLL specifies in its switchgear, energy automation, and building automation projects. The 2023 Schneider Sustainability Impact Award partnership signals overlapping customer bases in energy and building technology across DACH.
• Eaton Corporation: US-headquartered power management company with strong European electrical infrastructure and industrial automation presence. Competes with STOLL on switchgear, power distribution, and industrial control project work for similar end customers.
• ABB Ltd: Global electrification, motion, and process automation leader offering transformers, switchgear, and industrial automation products that overlap directly with STOLL's energy technology and automation segments, particularly for industrial customers across Europe.
• Siemens AG: Global broad-line industrial conglomerate active in electrical infrastructure, automation, and plant construction. STOLL already partners with Siemens (mutual relationship on automation trade events) and competes for many of the same mid-sized industrial electrification and automation contracts in the DACH region.

Others

• WAGO Kontakttechnik: German manufacturer of automation interconnection, PLC, and control cabinet technology widely specified in STOLL's automation projects. Adjacent ecosystem participant rather than direct competitor but shares the German Mittelstand industrial automation DNA.
• Rexel Germany (formerly REGRO): Major European electrical equipment distributor and project services provider active in DACH. Overlaps with STOLL on the supply side for switchgear, cabling, and project electrical materials used in its BoP deliveries.

Direct peers

• Griesemann Gruppe: German owner-managed EPC and engineering services group covering electrical, instrumentation, automation, and plant construction for the process industry. Closest headcount and family-owned Mittelstand analog to STOLL with overlapping industrial customer base.
• Kraftanlagen Gruppe: German EPC contractor specializing in energy infrastructure, power plant construction, and industrial plant engineering. Most direct comparable to STOLL in terms of size, DACH-mid-market focus, and combined engineering + execution service model for energy and industrial customers.

Regional players

• Stadtwerke and municipal utilities EPC arms: DACH municipal utility contractors who deliver localized transformer, switching station, and grid BoP services. Compete with STOLL for small and mid-sized regional utility tenders across southern Germany.
• Zeppelin (CAT) Power Systems / industrial EPCs: Mid-sized German industrial service providers offering energy, plant, and electrical infrastructure services in southern Germany. Comparable regional scope, Mittelstand scale, and customer base to STOLL's Allgäu-centric operations.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks1 record

Key highlights7 records

Customer concentration

• YouTubeyoutube.com/channel/UCsg6LvGN3Q4uZ54xoAgPmrg
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• LinkedInlinkedin.com/company/stollgruppe
• Instagraminstagram.com/stollgruppe/?hl=de
• Xx.com/StollGruppe

Compliance1 record

Revenue estimate

Valuation estimate

Number of profiles

Profiles5 records

Subsidiaries2 records

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 STOLL Group