Solarize
Solarize is a German SaaS company that provides an API-first, time-series-based meter-to-cash billing platform for decentralized energy products (Mieterstrom, GGV, dynamic tariffs, heat contracting, THG balancing) to municipal utilities, housing companies, and PV contractors in Germany.
- Company typePrivate
- Founded2020
- HeadquartersStuttgart, Germany
- Headcount1–10
- GTM typeB2B
- OfferingSoftware
What Solarize does
Solarize Energy Solutions GmbH is a Stuttgart- and Berlin-based German SaaS provider, founded in 2020, that operates an API-first, cloud-based meter-to-cash platform purpose-built for decentralized energy billing. The platform processes time-series smart-meter data and automates settlement for German-market constructs that legacy ERP systems cannot handle: Mieterstrom (tenant electricity), gemeinschaftliche Gebäudeversorgung (GGV), energy sharing, on-site PPAs, dynamic day-ahead tariffs under §41a EnWG, heat contracting, and THG quota balancing. The technology stack is microservices-based, ISO 27001 certified, and exposes a public API at api-docs.solarize.energy with pre-built integrations into SAP (Build Partner on BTP), Schleupen, DATEV, Wilken, Wodis Sigma, Nevaris, and four metering operators (wattline, Solandeo, metiundo, valenda).
Solarize targets three primary buyer segments — Stadtwerke and municipal utilities, housing companies and property owners (GBG Mannheim, GSG Berlin, Stadtmarken New Energy, BREMER), and PV contractors (ALVA, MARCLEY, WIRSOL, empact) — with a smaller emerging C&I segment. The company serves 200+ customers, 10,000+ meters, and 56 MWp of cumulative tenant-power capacity. Revenue is generated via annual SaaS subscriptions structured as a base price plus per-meter and per-user modules; pricing is quote-based and not publicly disclosed. Go-to-market combines direct enterprise field sales with a partner-led channel spanning SAP, Schleupen, epilot, and metering operators. The company is venture-backed by Point Nine Capital, Picus Capital, and Future Energy Ventures (FEV joined in February 2026), was ranked 6th in Notion Capital's Top 100 Cloud Challengers Europe 2024, and acquired Energy Pro GmbH in June 2026 to accelerate its heat billing module. Leadership is anchored by CEO Frederik Pfisterer (previously co-founder of Mambu), alongside co-founders Florian Feigenbutz and Andi Weiß, with a team of approximately 27 employees.
Solarize firmographics
Firmographics- Name
- Solarize
- Legal name
- Solarize Energy Solutions GmbH
- Website
- https://solarize.de
- Company type
- Private
- Founded year
- 2020
- Operating status
- Operating
- Headcount range
- 1–10 employees
- Short description
- Solarize is a German SaaS company that provides an API-first, time-series-based meter-to-cash billing platform for decentralized energy products (Mieterstrom, GGV, dynamic tariffs, heat contracting, THG balancing) to municipal utilities, housing companies, and PV contractors in Germany.
- Ownership category
- akta.pro rank
Solarize industry classification
Industry- Product category
- Energy Billing Software
- NAICS
- Solar Electric Power Generation (221114), Computing Infrastructure Providers, Data Processing, Web Hosting, and Related Services (518), Electric Power Generation, Transmission and Distribution (2211)
- SIC
- Services-Computer Programming, Data Processing, Etc. (7370), Electric Services (4911)
- akta.pro primary industry
- Solar Design, Engineering & Performance Software (PV Modeling, Digital Twins, Monitoring) (EUAMABAH)
- akta.pro secondary industries
- Community Solar Development & Subscription Management (EUAMAJAA), Solar Financing, Leasing & Ownership Platforms (Tax Equity, PPA, Securitization) (EUAMABAJ)
Keywords
Where Solarize is headquartered
LocationHeadquarters
- HQ city
- Stuttgart
- HQ country
- Germany
- HQ region
- Europe
Offices2 records
Markets served
Solarize business model
Business model- GTM type
- B2B
- Offering type
- Software
- Cost components
- Personnel, Technology or R&D, Marketing or Sales, Operations, Infrastructure
Revenue model
- SaaS Subscription - Annual Software License: Annual subscription fees based on software usage. Pricing is composed of a base price, additional meter charges, and additional user fees. The model is designed to scale with customer success, aligning the company's revenue with customer growth. The platform processes billing from metering data through to payment, and continuous software updates and regulatory compliance are included in the subscription fee.
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Subscription | Annual | Annual SaaS subscription with usage-based components |
Go-to-market motion2 records
Distribution channels6 records
Marketing channels8 records
Solarize product offering
Product offeringCore offering
Solarize operates a cloud-based SaaS meter-to-cash platform that automates billing for decentralized energy products, including tenant electricity (Mieterstrom), communal building supply (GGV), energy sharing, on-site PPAs, dynamic tariffs, heat contracting, and THG balancing. The platform functions as a specialized sub-ledger with an API-first, time-series-based architecture that integrates with German ERP systems, metering operators, and PV contractors to enable legally compliant billing across utilities, housing companies, and energy service providers.
Product overview
Solarize offers a cloud-based SaaS platform for automated billing and management of decentralized energy products, operating as a sub-ledger (Nebenbuch) in the meter-to-cash process. The platform consists of a core product portfolio covering six distinct modules: Mieterstrom & GGV (for both property owners and energy utilities/contractors), Dynamic Tariff Billing, THG Balancing for PV-linked EV charging, B2B Customer Billing, and Heat Contracting Billing. The platform processes time-series metering data, automates invoicing, supports ERP integration via API-first architecture, and handles complex settlement scenarios for residential and commercial customers. A key expansion came via the June 2026 acquisition of Energy Pro GmbH, which accelerates the development of the heat billing module.
Differentiator
Problem solved
Functional benefit
Products and services
- Mieterstrom & GGV for Property Owners Automated measurement, distribution, and billing of electricity flows for tenant electricity (Mieterstrom), communal building supply (GGV), and energy sharing in self-operation for property owners and housing companies.
- Mieterstrom & GGV for Utilities and Contractors Automated measurement, distribution, and billing of electricity flows for tenant electricity, communal building supply (GGV), and on-site PPAs under the contracting model for energy utilities (Stadtwerke, EVU) and contractors.
- Dynamic Tariff Billing Fully automated billing of day-ahead prices for household customers, compliant with the §41a EnWG dynamic tariff obligation effective January 2025.
- THG Balancing for PV Electricity Integrated software solution for precise GHG (THG) quota accounting for charging infrastructure combined with PV electricity, enabling higher THG quota revenues for utilities and mobility providers.
- B2B Customer Billing Automated billing of spot tariffs, PPAs, and tranches for commercial and industrial (B2B) customers receiving locally produced solar electricity.
- Heat Contracting Billing Legal compliance and efficiency in heat contracting billing (Wärmeabrechnung), including both centralized and district heating. Module development accelerated through the June 2026 acquisition of Energy Pro GmbH.
Quantifiable outcome
- Processes over 10,000 smart meters with high-frequency time-series data from metering to payment
- +6 more outcomes
Companies that use Solarize
Customer profileNamed customers19 records
Segments4 records
Ideal customer profiles3 records
Solarize technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- Yes
- API docs
- API detail
Core technology
AI maturity
App detail
Integration17 records
Feature6 records
Solarize partnerships and signals
Strategic signalPartnerships
15 partnerships are on record, tiered core and minor.
- Energy Pro GmbHcoreSolarize acquired Energy Pro GmbH, a company specializing in billing software for tenant electricity and heat, based in Dettingen unter Teck, Germany. The acquisition accelerates the development of Solarize's heat billing module by leveraging Energy Pro's deep industry expertise. Existing Energy Pro customers are expected to benefit from upgraded, future-ready infrastructure.
- Schleupen AGcoreSchleupen Partner for tenant electricity billing. Solarize automates billing of decentralized electricity products for Schleupen customers. Schleupen actively promotes Solarize as its preferred Mieterstrom billing solution to its customer base of energy utilities.
- SAPcoreSAP Build Partner with standard interfaces ensuring data exchange between Solarize and SAP systems. Integration with SAP BTP enables seamless connection between Solarize's meter-to-cash platform and SAP ERP customers. Enables energy companies using SAP to easily deploy Solarize for Mieterstrom and dynamic tariffs.
- epilotcoreepilot is a central hub for the modern energy world. A joint Mieterstrom Blueprint on epilot's marketplace enables rapid start in tenant electricity sales. Customer portal integration is also possible. Solarize billing is integrated into the epilot sales workflow.
- PolarsterncorePolarstern is an experienced residual electricity supplier in the tenant electricity environment, offering exclusive and attractive conditions for residual electricity supply contracts specifically for Solarize customers. Partnership enables automated supplier switching processes in tenant electricity projects.
- ALVA EnergiecoreALVA is a 360-degree partner accompanying property owners from planning through operation of solar power projects. ALVA realizes profitable tenant electricity business models for residential or commercial properties. Uses Solarize for automated billing.
- MARCLEYcoreMARCLEY offers an all-in-one solution for solar systems in the roof lease model. With Sale & Lease Back or leasing packages, MARCLEY is a partner for smaller property owners and cooperatives. Uses Solarize for billing across its GGV projects with 1,100+ meters.
- empact GmbHcoreempact's mission is to develop properties into decentralized power plants that supply themselves with renewable energy. For automated electricity billing, empact relies on Solarize.
- GIGA.GREENminorGIGA.GREEN provides planning, financing, installation, and operation of solar systems for large commercial properties.
- ImmoStromminorImmoStrom realizes PV installations and handles complete, legally compliant tenant electricity billing. For multi-family buildings from 4 units and commercial properties.
- mia Energieminormia Energie realizes tenant electricity projects for different building types and as a full-service partner handles all steps from technical planning to operation.
- Open District Hub (ODH)minorNetwork for neighborhood solutions and sector coupling. ODH brings knowledge from all value chain stages to create scalable solutions for intelligent and sustainable neighborhoods.
- Leipziger EnergieforenminorPlatform for networking the energy industry. As forum partners, Solarize is regularly in exchange and participates in selected events.
- Vedec (Verband für Energiedienstleistungen)minorVedec advocates for contracting and energy services to be established as the first solution for building supply. Solarize is an active member.
- KommunalDigital (VKU)minorService platform of the Association of Municipal Companies (VKU). Solarize is part of this ecosystem as a solution provider.
Scale indicators9 records
Recent moves6 records
Expansion highlights6 records
Solarize competitors and assessment
Company assessmentDirect peers
- epilot: epilot is a German SaaS platform for energy utilities covering customer journeys, sales, and product management. It overlaps directly with Solarize as a partner in the tenant electricity workflow (joint Mieterstrom Blueprint) and competes for utility wallet share around decentralized energy product enablement.
- Powercloud: Powercloud provides cloud-based ERP and billing software for utilities and energy suppliers in Germany. It targets the same municipal utility and energy service provider buyers as Solarize and offers overlapping capabilities in meter-to-cash and product configuration.
- KISTERS: KISTERS is a German IT vendor offering energy data management, forecasting, and billing solutions for utilities, grid operators, and energy traders. Its energy IT portfolio overlaps with Solarize's time-series data processing and complex billing use cases.
Emerging players
- GridX: GridX provides a cloud-based energy management platform for utilities and energy service providers, focusing on dynamic tariffs, flexibility markets, and prosumer management. It overlaps with Solarize in dynamic tariff billing and home energy product enablement for German utilities.
- Discovergy: Discovergy operates smart metering and energy data services for households and businesses in Germany. It overlaps with Solarize at the metering and dynamic tariff layer and serves many of the same utility and housing-company buyers.
Broad incumbents
- Schleupen AG: Schleupen is a major German ERP vendor for energy and utilities with deep installed base among Stadtwerke. While it partners with Solarize for tenant electricity billing, it could also expand its own billing scope to compete more directly with Solarize in Mieterstrom and GGV.
- Soptim: Soptim provides IT solutions for energy suppliers, grid operators, and metering point operators in Germany. It competes with Solarize in energy data and billing software for municipal and regional utilities.
- evergreen (now part of Salesforce): Evergreen was a German SaaS platform for municipal utilities covering CRM, billing, and customer management, now part of Salesforce's Industry Clouds. It competes with Solarize for the same municipal utility IT budget at a broader CRM/ERP layer.
- EnBW / EnBW Smart Energy: EnBW is one of Germany's largest energy suppliers and has invested in-house and via partnerships in decentralized energy platforms and Mieterstrom solutions. It represents a large incumbent that competes for the same end customers and partners as Solarize in the tenant electricity space.
Regional players
- Lichtblick SE: Lichtblick is a German green energy supplier with its own ZuhausePlattform for decentralized energy and customer management. As a Solarize customer for specific projects (e.g., Millerntor stadium PV) it also represents an adjacent competitive model for integrated energy platforms.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat6 records
Key risks6 records
Key highlights7 records
Customer concentration
Solarize social profiles
Digital presenceSolarize compliance and trust
Trust signalCompliance1 record
Solarize financial estimates
Financial estimateRevenue estimate
Valuation estimate
Solarize leadership team
Management profileNumber of profiles
Profiles6 records
Solarize subsidiaries and ownership
Company hierarchySubsidiaries1 record
Solarize funding detail
Funding detailFunding overview
Funding rounds3 records
Investors3 records
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Solarize M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Solarize
What does Solarize do?
Solarize operates a cloud-based SaaS meter-to-cash platform that automates billing for decentralized energy products, including tenant electricity (Mieterstrom), communal building supply (GGV), energy sharing, on-site PPAs, dynamic tariffs, heat contracting, and THG balancing. The platform functions as a specialized sub-ledger with an API-first, time-series-based architecture that integrates with German ERP systems, metering operators, and PV contractors to enable legally compliant billing across utilities, housing companies, and energy service providers.
Is Solarize a public or private company?
Solarize is a private company. It is classified as venture growth investor backed and is currently operating.
When was Solarize founded?
Solarize was founded in 2020. It employs 1 to 10 people.
Where is Solarize based?
Solarize is headquartered in Stuttgart, Germany, in the Europe region.
How does Solarize make money?
One revenue line is on record: saaS Subscription - Annual Software License.
Who are Solarize's main competitors?
Direct peers on record are epilot, Powercloud and KISTERS. Emerging players are GridX and Discovergy. Broad incumbents are Schleupen AG, Soptim, evergreen (now part of Salesforce) and EnBW / EnBW Smart Energy. Lichtblick SE is listed as a regional player.
Does Solarize have an API?
Yes. Solarize offers an API-first platform with open architecture enabling flexible integration. The platform is designed for seamless connection with ERP systems, metering infrastructure, CRM systems, and partner solutions. A public API documentation portal is available at api-docs.solarize.energy. The platform supports data exchange, automated invoice generation, and real-time metering data synchronization. Microservices architecture enables modular integration. The API-first philosophy is described as enabling integration of AI applications and customer-facing apps. Developer documentation is at api-docs.solarize.energy.
What industry is Solarize in?
Solarize's product category is Energy Billing Software. Its primary akta.pro industry code is EUAMABAH, Solar Design, Engineering & Performance Software (PV Modeling, Digital Twins, Monitoring), with a secondary code of EUAMAJAA, Community Solar Development & Subscription Management. Its NAICS code is 221114 and its SIC code is 7370.