KIOTO Clear Energy AG

What KIOTO Clear Energy AG does

KIOTO Clear Energy AG operates through its Sonnenkraft subsidiary (Sonnenkraft GmbH), an Austrian solar energy systems manufacturer founded in 1991 and headquartered in St. Veit an der Glan, Carinthia. The company designs, produces, and distributes a complete residential and commercial renewable-energy stack under the Sonnenkraft and KIOTO SOLAR brands, including photovoltaic modules (standard, bifacial/double-glass, high-glare, high-snow-load, shade-resistant, and plug & play variants), hybrid and string inverters (4 kW to 30 kW), modular battery storage (12.44 to 29.03 kWh) including the SKB-MAX all-in-one AC storage system, solar thermal collectors, and matched hot-water and buffer storage tanks.

The underlying technology base includes rear-side contacted module architecture, double-glass frameless modules with DIBt approval for building integration, and the proprietary Sonnentank H2O thermal storage platform. Digital tools — an online product Configurator and the Sonnenkraft Expert Tool for certified installers — sit alongside a monitored app/web portal for installed systems. Manufacturing is positioned as Made in Austria at CO2-friendly facilities, with an ongoing Sonnenkraft Campus development converting the headquarters site into an expanded innovation and production complex.

Commercially, Sonnenkraft operates a hybrid go-to-market: direct-to-consumer reach via the online configurator and webinars, combined with B2B distribution through a certified installer network, regional dealers, and participation in major industry events such as Intersolar Europe. Revenue is generated through one-time hardware sales of modules, inverters, storage, and thermal products to residential property owners, commercial/industrial businesses, and installer partners, with a SMARTFOX partnership extending the offering into integrated energy management. The company claims over 1,000,000 lifetime customers and serves primarily the DACH and broader European market.

Name

KIOTO Clear Energy AG

Legal name

Sonnenkraft GmbH

Website

https://kioto.com

Company type

Private

Founded year

1991

Operating status

Operating

Headcount range

1–10 employees

Short description

KIOTO Clear Energy AG, via its Sonnenkraft subsidiary, is an Austrian manufacturer founded in 1991 that produces and distributes PV modules, hybrid inverters, battery storage, and solar thermal systems to residential and commercial customers across Europe through certified installers and an online configurator.

Ownership category

akta.pro rank

Product category

Solar Energy Equipment

NAICS

Battery Manufacturing (33591)

akta.pro primary industry

Solar PV Module & Cell Manufacturing (Crystalline, Thin-Film) (EUAMAHAA)

akta.pro secondary industries

Solar Inverters, Power Optimizers & MLPE Manufacturing (EUAMAHAB), Solar PV Module Manufacturing (Cells, Modules, Thin-Film) (EUAMABAD), Solar Roofing & Roof-Mounted PV Systems (IMADAFAO)

Keywords

• Photovoltaic modules
• Solar storage systems
• Hybrid inverters
• Solar thermal collectors
• Hot water storage tanks

Headquarters

HQ city

St. Veit an der Glan

HQ country

Austria

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B and B2C

Offering type

Hardware or Manufacturing

Cost components

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

Revenue model

1. Solar Module Sales: Sale of photovoltaic modules under KIOTO SOLAR brand including standard, high-glare, high-snow-load, shade-resistant, and plug & play variants. One-time purchase model for hardware products.
2. Inverter Sales: Sales of hybrid and standard inverters ranging from 4kW to 30kW capacity for residential and commercial solar installations.
3. Battery Storage Systems: Sales of modular battery systems (12.4 to 29 kWh), Sonnentank storage units, and integrated SKB-MAX all-in-one AC storage solutions.
4. Solar Thermal Products: Sales of solar collectors including design tub collectors (SKR500) and plug & flow module collectors (PFM series) for hot water generation.

Pricing tiers

Go-to-market motion1 record

Distribution channels3 records

Marketing channels6 records

Core offering

KIOTO Clear Energy AG, through its subsidiary Sonnenkraft GmbH, manufactures and sells photovoltaic modules under the KIOTO SOLAR brand, hybrid and standard solar inverters, modular battery storage systems, plug-and-play mini-PV systems (SONNENKRAFTWERK), solar thermal collectors, and modular hot-water storage tanks (Sonnentank). The company delivers complete integrated solar system solutions — combining PV, inverter, battery storage, and thermal components — to residential homeowners, commercial and industrial customers, and certified installer partners across Europe.

Product overview

KIOTO Clear Energy AG operates through its Sonnenkraft brand, offering comprehensive renewable energy system solutions comprising photovoltaic (PV) modules, inverters, battery storage systems, solar thermal collectors, and water storage solutions. The product portfolio includes solar modules (SOLAR-MODUL 410-470 Wp, POWER HC, POWER HC ALPIN, POWER ALPIN, POWER MAXIM variants), frameless/framed solar glass (Sonnengläser) for roofing/facades, Sonnenkraftwerk plug & play systems, hybrid and standard inverters (4-30 kW), battery storage (SONNENKRAFT Batterie 12.4-29 kWh, SKB-MAX all-in-one AC storage), solar thermal collectors (SKR500 design collector, PFM module collectors), and water storage tanks (COMPACT, COMFORT, SONNENTANK systems). Supporting digital tools include the Sonnenkraft Configurator and Expert Tool. The company also produces photovoltaic modules under the KIOTO SOLAR brand.

Differentiator

Problem solved

Functional benefit

Brands

• KIOTO SOLAR: Photovoltaic module brand produced by Sonnenkraft
• SONNENTANK
• SONNENKRAFTWERK
• SKB-MAX

Products and services

• KIOTO SOLAR Photovoltaic Modules
• Sonnenläser Solar Glass PV Modules (BIPV)
• SONNENKRAFTWERK Plug & Play Mini-PV System
• SONNENKRAFT Hybrid and Standard Solar Inverters
• SONNENKRAFT Battery Storage Systems
• SONNENKRAFT Solar Thermal Collectors
• Sonnentank Hot-Water Storage Tanks

Quantifiable outcome

• Buildings can reduce energy costs by up to 75%
• +3 more outcomes

Named customers1 record

Segments3 records

Ideal customer profiles3 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature5 records

Partnerships

One partnership is on record.

• SMARTFOXcoreStrategic or Co-development PartnerSonnenkraft and SMARTFOX partnership combining forces to offer customers holistic energy solutions that are efficient, intelligent, and sustainable. The partnership focuses on comprehensive energy solutions for customers.

Scale indicators4 records

Recent moves6 records

Expansion highlights3 records

Direct peers

• SolarEdge Technologies: Israeli-listed inverter and optimizer manufacturer with growing European residential storage offering — competes on inverter architecture and integrated PV+storage for the same residential and small commercial segments.
• Enphase Energy: US-headquartered microinverter and home battery (IQ Battery) manufacturer with strong European residential footprint — competes head-to-head with Sonnenkraft's hybrid inverter and modular storage systems.
• Solarwatt GmbH: German premium PV module and integrated solar/storage system manufacturer serving residential and C&I customers with in-house modules, batteries, and installer channels — the closest analog to Sonnenkraft's full-stack European model.
• Fronius International GmbH: Austrian-headquartered manufacturer of solar inverters and energy storage solutions serving European residential and C&I markets — directly comparable on inverter/storage portfolio, geography, and DACH installer channel.
• SMA Solar Technology AG: Germany-based global inverter and energy management specialist, one of the largest European players in residential, commercial and utility-scale PV inverters plus storage integration — a direct competitor in hybrid inverter and storage offerings.
• REC Group: European-headquartered (Norway) PV module manufacturer with premium positioning in residential and commercial segments — directly comparable as a non-Asian premium module brand targeting European rooftops.

Broad incumbents

• Trina Solar: Global tier-1 PV module manufacturer with vertically integrated cell-to-system capabilities and a major European residential/commercial footprint — competes primarily on scale and price but increasingly on integrated storage solutions.
• BYD Energy Storage: Chinese battery and energy storage giant increasingly serving European residential storage markets — a key competitor in the modular and all-in-one storage system segments where Sonnenkraft's SKB-MAX competes.
• LONGi Green Energy Technology: World's largest monocrystalline silicon wafer and module producer — sets the cost benchmark that Sonnenkraft's premium Austrian pricing must justify across European residential and commercial installations.
• SunPower Corporation: US-headquartered premium residential and commercial solar plus storage provider with European operations — overlapping in premium rooftop positioning and integrated PV+storage offering.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• YouTubeyoutube.com/channel/UCcCNGlIP9t2C90XbUqC1veA
• Facebookfacebook.com/Sonnenkraft
• LinkedInlinkedin.com/company/kioto-clear-energy-ag
• Instagraminstagram.com/sonnenkraftaustria

Compliance1 record

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 KIOTO Clear Energy AG