What Stadtwerke Iserlohn does

Stadtwerke Iserlohn GmbH is a German municipal utility (Stadtwerke) headquartered in Iserlohn, North Rhine-Westphalia, providing integrated energy, water, and heating services to residential and commercial customers across Iserlohn and the surrounding municipalities of Nachrodt-Wiblingwerde, with additional coverage in parts of Altena and Schalksmühle. The company operates as the designated Grundversorger (basic supplier) for electricity and gas, and functions as the regulated distribution network operator, owning over 1,300 km of electricity cables and approximately 330 km of gas pipelines. Its sister company, Bädergesellschaft Iserlohn mbH, operates the Seilerseebad spa, Aquamathe swimming pool, and Eissporthalle ice arena, serving approximately 300,000 visitors annually to the Seilerseebad alone.

The core product portfolio spans electricity, natural gas, drinking water (SauerlandWasser), and district heating (Fernwärme), supplemented by photovoltaic leasing from €99 per month, balcony power plants, EV charging infrastructure, e-car sharing, THG quota management (paying €260 annually to EV owners), and smart meter rollout under the MsbG framework. The underlying technology stack includes a virtual power plant (WIRtuelles Kraftwerk Iserlohn / WIKI) that aggregates distributed energy resources — PV, wind, hydro, nine combined heat and power (BHKW) units with up to 90% efficiency, biomass, storage, and EVs — built in partnership with Bergische Universität Wuppertal and co-funded by EFRE.NRW. The EnergyConnect mobile app, operated by vendor clever-PV, enables customers to monitor consumption, submit meter readings, and transition from passive consumers to active prosumers.

Go-to-market combines a digital self-service layer (Servicewelt portal, EnergyConnect app, online tariff calculators), inside sales via phone hotlines, a walk-in customer service center (Kundenzentrum), and a field sales team of named representatives conducting on-site energy consultations. Customer segments include private households (primary), commercial and industrial customers (>100,000 kWh accounts handled by dedicated sales contact Thomas Stoltmann), tradespeople (via an installer directory), housing industry and property management, and energy producers feeding into the network. Revenue is generated primarily through consumption-based utility charges and regulated network fees under the Energy Economy Act (EnWG), with additional recurring income from PV leases, THG quota commissions, and EV charging fees. The company operates under the 'Heimatversorger' (home supplier) brand identity, emphasizing local roots and community engagement, and was awarded the Stadtwerke Award in September 2022.

Name

Stadtwerke Iserlohn

Legal name

Stadtwerke Iserlohn GmbH

Website

https://stadtwerke-iserlohn.de

Company type

Private

Founded year

2000

Operating status

Operating

Headcount range

1–10 employees

Short description

Stadtwerke Iserlohn GmbH is a German municipal utility supplying electricity, gas, drinking water, and district heating to residential and commercial customers across Iserlohn and neighboring municipalities. It also operates a virtual power plant, e-mobility infrastructure, PV leasing, and regulated network infrastructure under the 'Heimatversorger' brand.

Ownership category

akta.pro rank

Product category

Municipal Energy and Water Utility Services

NAICS

Electric Power Generation, Transmission and Distribution (2211), Electric Power Distribution (221122), Steam and Air-Conditioning Supply (221330), Water, Sewage and Other Systems (2213)

SIC

Electric Services (4911), Cogeneration Services & Small Power Producers (4991), Electric, Gas & Sanitary Services (4900)

akta.pro primary industry

District Energy & Community CHP (District Heating/Cooling Networks) (EUACAKAH)

akta.pro secondary industries

Behind-the-Meter Aggregators Acting as DSO (Virtual Power Plant / Community Energy Operators) (EUADABAG), Resilience & Backup Power Solutions (Critical Facilities, Islanding) (EUAMAJAK), SCADA/DMS/OMS Integration, Upgrades & Managed Services (EUAEANAE)

Keywords

• Electricity supply
• Natural gas distribution
• Drinking water supply
• District heating services
• E-mobility infrastructure

Headquarters

HQ city

Iserlohn

HQ country

Germany

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B and B2C

Offering type

Services

Cost components

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

Revenue model

1. Electricity Supply & Distribution: Electricity supply to residential and business customers in the Stadtwerke Iserlohn network area, including standard tariffs, heat storage tariffs, heat pump tariffs, EV tariffs, and solar tariffs. Revenue is generated through consumption-based energy charges plus network fees. The company is also the default basic supplier (Grundversorger) for electricity.
2. Gas Supply & Distribution: Natural gas supply to residential and commercial customers with consumption-based pricing, including gas network operation as regulated monopoly. The company serves as the designated gas basic supplier (Grundversorger) for the network area.
3. Drinking Water Supply: Drinking water supply (SauerlandWasser) to households and businesses in the network area, sold on a consumption basis with periodic billing.
4. District Heating (Fernwärme): Supply of thermal energy through the company's expanding district heating network. Offered with and without upfront acquisition cost (Contracting model), providing recurring revenue from heat delivery.
5. E-Mobility Services: Public EV charging stations, private charging box installation, e-car sharing program, THG quota (greenhouse gas reduction quota) management for EV owners, generating revenue through charging fees and the THG quote premium.
6. Leisure Facilities (via Bädergesellschaft): The sister company Bädergesellschaft Iserlohn operates the Seilerseebad spa, Aquamathe swimming pool, and Eisporthalle ice arena, which generate revenue from admission fees and ancillary services. Approximately 300,000 visitors per year to the Seilerseebad alone.
7. Photovoltaic Systems (PV Pacht): Leasing/Pacht model for PV systems starting at €99/month, providing customers with solar generation capability and generating recurring lease revenue from subscribers.
8. Network Connection & Metering Services: Charges for grid connection, metering point operation (Messstellenbetrieb) for modern and intelligent measurement systems, and network charges regulated under the Energy Economy Act (EnWG). Revenue includes connection fees and recurring metering fees.

Pricing tiers

Go-to-market motion4 records

Distribution channels6 records

Marketing channels10 records

Core offering

Stadtwerke Iserlohn GmbH is the municipal utility (Stadtwerke) for the city of Iserlohn and surrounding municipalities, supplying electricity, natural gas, drinking water, and district heating to residential and commercial customers as the designated basic supplier (Grundversorger). It operates the local electricity grid (over 1,300 km of cables) and gas network (~330 km), and offers complementary services including e-mobility charging, PV leasing, smart metering, and a virtual power plant (WIKI) that aggregates distributed energy resources for grid flexibility.

Product overview

Stadtwerke Iserlohn operates as a regional energy utility offering an integrated portfolio of energy supply and infrastructure services. The core offering comprises electricity and gas supply, district heating (Fernwärme), and drinking water services. The product ecosystem includes photovoltaic solutions (PV leasing, balcony power plants), e-mobility services (charging stations, E-CarSharing), and smart meter infrastructure. Digital access is provided through the EnergyConnect App and Servicewelt customer portal. Advanced energy management is enabled through the WIRtuelles Kraftwerk (virtual power plant) for coordinating distributed energy resources, PowerSharing community energy platform, and Kraft-Wärme-Kopplung (CHP) facilities. The company also operates electricity and gas grid infrastructure spanning over 1,600 km combined.

Differentiator

Problem solved

Functional benefit

Brands

• Heimatversorger: Brand identity tagline used by Stadtwerke Iserlohn referring to their role as the local home energy provider.
• EnergyConnect
• WIKI (WIRtuelles Kraftwerk Iserlohn)
• PowerSharing

Products and services

• Electricity Supply (Strom) Electricity supply service for residential households and commercial customers in the Iserlohn network area, offering standard tariffs plus specialized rates for heat storage heaters, heat pumps, EV charging, and solar customers; customers are billed on a consumption basis with monthly settlements.
• Natural Gas Supply (Gas) Natural gas supply for heating and energy needs, available to residential and business customers in the Iserlohn network area, including transition support from L-Gas to H-Gas; consumption-based billing with postcode-specific tariffs.
• Drinking Water Supply (SauerlandWasser) Drinking water supply to households and businesses in the Iserlohn network area (SauerlandWasser brand), sold on a consumption basis with periodic billing, plus ancillary services such as water hardness queries and standpipe rental.
• District Heating (Fernwärme) District heating service delivering thermal energy to residential and commercial buildings through Stadtwerke Iserlohn's local heating network, available via a contracting model that removes upfront acquisition costs for the customer's heating station.
• E-Mobility Services E-mobility offering for private and business customers combining public EV charging stations across Iserlohn, E-CarSharing via mobile app, discounted charging box installation, and administration of the THG greenhouse-gas quota with an annual premium of at least €260 for EV owners.
• Photovoltaic Systems (PV-Lease / PV-Pacht) Solar energy solutions for private and commercial customers, including a PV leasing model (PV-Pacht) starting at €99 per month, balcony power plants, and registration of PV installations; enables customers to generate solar electricity without upfront capital outlay.

Quantifiable outcome

• BHKW efficiency of up to 90% total efficiency (electricity + heat), more than double that of conventional coal-fired power plants
• +3 more outcomes

Segments5 records

Ideal customer profiles4 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature6 records

Partnerships

Eight partnerships are on record, tiered core and minor.

• Bergische Universität Wuppertal (Research Group: Energy Markets and Flexibility Management)coreStrategic or Co-development PartnerThe university serves as a research partner in the WIKI (WIRtuelles Kraftwerk Iserlohn) virtual power plant project, providing academic expertise in energy markets and flexibility management. The partnership is co-funded by EFRE.NRW (European Regional Development Fund).
• Bädergesellschaft Iserlohn mbHcoreStrategic or Co-development PartnerThe baths company is a sister organization (Schwestergesellschaft) of Stadtwerke Iserlohn, operating leisure facilities including the Seilerseebad, Aquamathe, and Eisporthalle. Bädergesellschaft participates in the WIKI virtual power plant as a flexibility provider (thermal storage through swimming pools).
• THIELE GmbH & Co. KGcoreStrategic or Co-development PartnerTHIELE GmbH & Co. KG is a local industrial company and partner in the WIKI virtual power plant project, contributing flexibility from its industrial operations to the regional energy management system.
• Gesellschaft für Wirtschaftsförderung Iserlohn mbH (GfW)minorStrategic or Co-development PartnerThe local economic development agency supports the WIKI project as a stakeholder in regional economic promotion, helping to connect local businesses with the virtual power plant ecosystem.
• carbonify GmbH (Gräfelfing)coreTechnology or IntegrationCarbonify handles the processing of the Treibhausgasminderungsquote (THG quota) for EV owners on behalf of Stadtwerke Iserlohn. This includes document verification via AI/OCR, quota registration with the Umweltbundesamt, and quota trading. Stadtwerke and carbonify operate as joint controllers under GDPR Art. 26.
• clever-PV GmbH (Landsberg am Lech)coreTechnology or IntegrationClever-PV GmbH provides technical support and operation of the EnergyConnect app for Stadtwerke Iserlohn, acting as an order processor (Auftragsverarbeiter) under GDPR for the app's functionality.
• Risse+WilkeminorStrategic or Co-development PartnerStadtwerke Iserlohn partnered with Risse+Wilke to build the largest solar installation in Iserlohn (July 2024), demonstrating collaboration with local construction firms on renewable energy projects.
• STADTprojekt GmbHminorStrategic or Co-development PartnerSTADTprojekt GmbH is developing the WaldStadtQuartier, an innovative residential district in Iserlohn. Stadtwerke Iserlohn is involved in supplying energy to this new development, representing a forward-looking urban development partnership.

Scale indicators8 records

Recent moves7 records

Expansion highlights6 records

Regional players

• Stadtwerke Hagen: Public utility serving Hagen, directly neighboring the Märkischer Kreis region where Iserlohn operates. Comparable multi-utility offering (electricity, gas, water, district heating, e-mobility) with similar regulated-Grundversorger structure and mid-sized municipal footprint. Most direct geographic peer.
• ENERVIE / Mark-E: Energy and infrastructure provider operating in the Märkischer Kreis and adjacent regions, with electricity/gas/district heating services and grid operations. Operates closely overlapping service territory with Stadtwerke Iserlohn as a regional multi-utility.
• Stadtwerke Lüdenscheid: Neighbor-region municipal utility serving Lüdenscheid in the Märkisches Sauerland. Comparable size, similar Southwestphalian multi-utility model with electricity, gas, water, and energy-transition services.

Direct peers

• Lichtblick (Lichtblick SE): German pioneer in virtual power plants and home-energy management (ZuhauseKraftwerk / Schwarmstrom). Comparable on the VPP and prosumer-customer engagement axes, though Lichtblick operates without owning a distribution grid.

Emerging players

• Next Kraftwerke: Cologne-headquartered virtual power plant operator that aggregates distributed generation, storage, and flexible loads across Germany. Direct functional comparable to Stadtwerke Iserlohn's WIKI VPP, operating at much larger national scale.
• Sonnen (sonnen GmbH): German residential battery and energy-community (sonnenCommunity) provider. Comparable on the prosumer/microgrid and community-energy engagement dimension, though operating without local distribution-grid ownership.

Broad incumbents

• Stadtwerke Bonn (SWB): Larger municipal multi-utility (electricity, gas, water, district heating) operating as Grundversorger in a comparable German mid-size city. Useful benchmark for the integrated Stadtwerke model, though at materially larger scale.
• NEW AG (Niederrheinwerke): Regional multi-utility in the Lower Rhine region serving multiple municipalities with electricity, gas, water, and energy services. Comparable integrated portfolio and regulated multi-municipality operating model.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks5 records

Key highlights7 records

Customer concentration

• YouTubeyoutube.com/channel/UCbP7ib0id0V-9F_pnMGQ76Q/videos
• Facebookfacebook.com/swiserlohn
• Instagraminstagram.com/stadtwerke_iserlohn
• Xx.com/heimatversorger

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Subsidiaries1 record

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 Stadtwerke Iserlohn