International Solar Energy Society

What International Solar Energy Society does

The International Solar Energy Society (ISES) is a German-registered not-for-profit membership association (eingetragener Verein, e.V.) founded in 1954 and headquartered in Freiburg, Germany. It operates as the global umbrella society for solar energy research, education, and advocacy, with a stated mission of advancing 100% renewable energy and serving a worldwide community through national sections spanning Europe, North America, South America, Asia, Africa, the Middle East, and Oceania. Governance is provided by an elected Board of Directors of up to 19 members (7 ExCo + 12 elected members), supported by a small headquarters team of three staff.

ISES's core offerings are its publications and convenings. The Solar Energy Journal, published continuously since 1957 and distributed via ScienceDirect, is the organization's flagship asset with an Impact Factor of 6.6 and CiteScore of 12.6; Solar Energy Advances is a companion publication. The biennial Solar World Congress and EuroSun conference series (the latter co-organized with the IEA Solar Heating and Cooling Programme) anchor its event business. Complementary products include monthly webinars, the Young ISES youth initiative, the InCoRE education initiative, the ISES Online Museum of Solar Energy, and a monthly column in pv magazine. Awards programs (Farrington Daniels, Achievement through Action, Global Leadership, ISES Fellows, Renewable Transformation Challenge, and the Karl Böer Solar Energy Medal of Merit) reinforce reputational positioning.

ISES is financed through individual memberships (Student, Regular, Silver 5-year, Gold Lifetime tiers, with lower-income-country discounts), corporate memberships (companies and institutions such as Solatom, InES, Global Solar Council, SERIS, IMDEA, and others), conference and event fees, publication subscriptions, and grants. Its strategic positioning rests on a 70-year institutional legacy, a federated network of 25+ national sections, and partnerships with IEA SHC, the World Bank, the International Solar Alliance, REN21, IRENA Coalition for Action, the Global Solar Council (founding member since COP21), SolarPower Europe, and Intersolar. The organization is not publicly traded, has no disclosed funding rounds or external investors, and has no parent company.

Name

International Solar Energy Society

Legal name

International Solar Energy Society e.V.

Website

https://ises.org

Company type

Private

Founded year

1954

Operating status

Operating

Headcount range

1–10 employees

Short description

International Solar Energy Society (ISES) is a Freiburg, Germany-based not-for-profit association founded in 1954 that unites a global community of solar energy researchers, industry professionals, students, and corporate members through peer-reviewed publications (Solar Energy Journal), biennial conferences (Solar World Congress, EuroSun), webinars, and national sections across all continents.

Ownership category

akta.pro rank

Product category

Renewable Energy Membership Association

NAICS

Business Associations (813910)

SIC

Services-Membership Organizations (8600), Services-Commercial Physical & Biological Research (8731)

akta.pro primary industry

Solar Workforce, Training & Safety Services (Installer Training, Certification, EHS) (EUAMABAO)

Keywords

• Renewable energy research
• Solar energy publications
• Solar energy conferences
• Membership association
• Clean energy advocacy

Headquarters

HQ city

Freiburg

HQ country

Germany

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B and B2C

Offering type

Services

Cost components

Personnel, Operations, Marketing or Sales, Technology or R&D, Others

Revenue model

1. Individual Memberships: Annual memberships for individuals with tiered pricing including student, regular, silver (5-year), and gold (lifetime) options. Lower-income country discounts available. Members receive access to publications, events, webinars, and networking.
2. Corporate Memberships: Annual memberships for companies and institutions with tiered benefits. Corporate members are listed on the ISES website and have access to special services and visibility.
3. Conference and Event Fees: Revenue from organizing EuroSun and Solar World Congress conferences, as well as webinar programs and special events.
4. Publication Revenues: Revenue from Solar Energy Journal subscriptions and special publication services, including subscriptions bundled with memberships.

Pricing tiers

Go-to-market motion1 record

Distribution channels3 records

Marketing channels10 records

Core offering

International Solar Energy Society (ISES) is a global not-for-profit membership organization that advances solar and renewable energy through publications, conferences, and networking. Its core offerings include the peer-reviewed Solar Energy Journal (Impact Factor 6.6, published since 1957), biennial conferences (EuroSun and Solar World Congress), monthly webinars, an awards program, and individual and corporate memberships. The society also operates youth initiatives, the InCoRE education program, and the Online Museum of Solar Energy.

Product overview

The International Solar Energy Society (ISES) operates as a not-for-profit membership organization (e.V.) offering a portfolio of products and services centered on advancing solar energy globally. The core offerings include the Solar Energy Journal (peer-reviewed publication with Impact Factor 6.6), biennial conferences (ISES Solar World Congress and EuroSun Conferences), monthly webinars, and an awards program. ISES provides Individual and Corporate Membership tiers with benefits including journal access, event discounts, and networking through the International Experts Network. Additional initiatives include Young ISES (youth program), InCoRE education initiative, ISES Online Museum of Solar Energy, and the monthly ISES Column in pv magazine. The society is headquartered in Freiburg, Germany and is governed by an elected Board of Directors with support from a small headquarters team.

Differentiator

Problem solved

Functional benefit

Brands

• Solar Energy Journal: The official journal of ISES, published continuously since 1957, covering solar energy science and technology applications
• EuroSun
• ISES Solar World Congress
• Young ISES
• ISES Online Museum of Solar Energy

Products and services

• Solar Energy Journal The official peer-reviewed journal of ISES covering the science and technology of solar energy applications, including photovoltaics, solar thermal, concentrating solar power, energy storage, and renewable energy systems integration. Available to members and through institutional subscriptions on ScienceDirect.
• EuroSun Conferences Biennial international conference series held in cities across Europe covering solar energy research and applications, co-organized with the IEA Solar Heating and Cooling Programme. EuroSun2026 scheduled for September in Germany.
• ISES Solar World Congress ISES flagship biennial international congress on solar energy bringing together researchers, industry professionals, and policymakers. Solar World Congress 2025 held in Fortaleza, Brazil; next event is SWC2027.
• Webinars Monthly webinar programs featuring presentations by ISES members, Board of Directors, staff, and other contributors on solar energy topics. Open to members and sometimes non-members.
• Individual Memberships Annual memberships for individuals with tiered pricing including student, regular, silver (5-year), and gold (lifetime) options. Lower-income country discounts available. Members receive access to publications, events, webinars, and networking.
• Corporate Memberships Annual memberships for companies and institutions with tiered benefits. Corporate members are listed on the ISES website, receive directory listings, conference participation, and networking opportunities with the global solar community.
• Young ISES Youth program providing opportunities for early-career solar energy professionals including board representation, UN event participation, and international representation.
• InCoRE Education Initiative International Cooperation in Renewable Energy education initiative promoting renewable energy education and training globally.
• ISES Online Museum of Solar Energy Online museum documenting the history and evolution of solar energy technology and the renewable energy movement.
• ISES Awards Program Awards program including Farrington Daniels Award, Achievement through Action Award, Global Leadership Award, ISES Fellows, Renewable Transformation Challenge, and Solar Energy Journal Best Paper Award.
• ISES Column in pv magazine Monthly column in pv magazine written by ISES Board members and experts covering solar energy trends, policy, and market developments.
• Conference Proceedings Proceedings from ISES conferences including Solar World Congress and EuroSun, containing scientific papers and presentations.
• International Experts Network Network connecting ISES members with expertise across various solar energy domains for collaboration and consultation.

Quantifiable outcome

• Solar Energy Journal Impact Factor 6.6, CiteScore 12.6
• +1 more outcomes

Named customers8 records

Segments5 records

Ideal customer profiles4 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

15 partnerships are on record, tiered core, major, strategic and minor.

• IEA Solar Heating and Cooling ProgrammecoreStrategic or Co-development PartnerIEA SHC co-organizes the EuroSun conference series with ISES. Planning for EuroSun2028 conference is underway between ISES and IEA SHC. The partnership involves joint conference organization and knowledge exchange in solar thermal and heating technologies.
• World BankmajorStrategic or Co-development PartnerThe World Bank is listed as a partner organization supporting ISES initiatives. World Bank's ESMAP/ESP program collaborates on energy storage working groups.
• International Solar Alliance (ISA)coreStrategic or Co-development PartnerISA is a coalition of countries devoted to easing solar deployment globally. ISES collaborates with ISA through various initiatives. Dr. Gurleen Kaur, ISES ExCo member, is a Technology and Solar Specialist at ISA.
• REN21coreStrategic or Co-development PartnerREN21 is the Renewable Energy Policy Network for the 21st Century. ISES is listed as a partner and maintains close collaboration, including participation in REN21 events and joint policy initiatives.
• SolarPower EuropemajorGTM or Marketing PartnerSolarPower Europe is a European solar industry association. ISES partnership involves joint advocacy and promotion of solar energy in Europe.
• Global Solar CouncilcoreStrategic or Co-development PartnerISES is a founding member of the Global Solar Council, serving on its Board of Directors since its launch at COP21 in Paris (2015). The Council serves as global voice for advancing the photovoltaic industry.
• GWNET (Global Women's Network for the Energy Transition)strategicStrategic or Co-development PartnerGWNET aims to empower women in the sustainable energy sector. Christine Lins, former REN21 Executive Secretary and ISES Board Member, co-founded GWNET in May 2017.
• IRENA Coalition for ActionmajorStrategic or Co-development PartnerISES participates in the IRENA Coalition for Action, a non-governmental multi-stakeholder platform for promoting rapid uptake of renewables.
• Solar Cookers InternationalminorGTM or Marketing PartnerSCI is listed as an ISES partner organization, collaborating on solar cooking and clean energy access initiatives.
• Power for AllminorGTM or Marketing PartnerPower for All is listed as an ISES partner, working on decentralized renewable energy advocacy.
• Climate Action NetworkminorGTM or Marketing PartnerCAN is a network of NGOs working on climate policy. ISES partnership supports climate advocacy and renewable energy messaging.
• IntersolarcoreStrategic or Co-development PartnerSince 2000, ISES has proudly supported Intersolar—the world's largest solar energy industry trade fair. ISES offers members free 3-day tickets to Intersolar Europe exhibitions. ISES ExCo Dr. Eicke Weber served as Chairman of Intersolar North America Conference.
• pv magazinemajorGTM or Marketing PartnerISES has a monthly column in pv magazine featuring expert analysis on solar energy topics. The partnership provides visibility for ISES expertise and research.
• IEA PVPS TaskmajorStrategic or Co-development PartnerISES Board member Andreas Kazantzidis participates in IEA PVPS Task dedicated to solar resource for high penetration and large scale applications.
• Global Sustainable Energy Solutions Pty Ltd (GSES)minorOthersGSES is a co-founding corporate member of ISES, providing professional engineering and training services across the renewable energy sector.

Scale indicators6 records

Recent moves6 records

Expansion highlights5 records

Broad incumbents

• REN21 (Renewable Energy Policy Network for the 21st Century): Global multi-stakeholder renewable energy policy network that ISES partners with. Operates the widely cited Global Renewables Outlook report and is a comparable international convener in the renewable-energy policy space.
• SolarPower Europe: Larger, better-funded European solar industry association with broader corporate membership and active policy advocacy. Comparable mission around solar advocacy but with a more industry/commercial lens than ISES's research focus.
• International Solar Alliance (ISA): Intergovernmental organization of 120+ solar-resource-rich countries with a comparable global solar-advocacy mission. ISES collaborates formally with ISA, and ISA board members overlap with ISES leadership.
• International Energy Agency (IEA) PVPS: IEA Technology Collaboration Programme on photovoltaic power systems. ISES board members participate in IEA PVPS Task groups, and the two organizations share research and policy audiences in the solar-power domain.

Direct peers

• American Solar Energy Society (ASES): U.S. national counterpart to ISES, operating as a membership-based solar energy advocacy and education organization. Listed as a regional 'subsidiary' within ISES's structure, making it the closest direct peer in mission and community model.
• Swissolar: Swiss national solar energy association. Functionally identical to ISES in its country-specific role — research dissemination, member services, and policy advocacy — and listed as an ISES regional section.
• Global Solar Council: International solar industry advocacy coalition of which ISES is a founding member. Shares the 'united voice for solar' framing and serves overlapping enterprise members in the global PV value chain.
• Deutsche Gesellschaft für Sonnenenergie (DGS): German national solar energy society with the same foundational mission as ISES (research dissemination, advocacy, education). Listed as a regional ISES section, with overlapping event and publication activity in the DACH region.

Emerging players

• European Solar Manufacturing Council (ESMC): Industry-led European council focused on solar PV manufacturing advocacy. Overlaps with ISES's policy advocacy scope but is narrower (manufacturing) and more politically focused than ISES's research mandate.
• International Renewable Energy Conference (IREC): Biennial international ministerial-level conference on renewable energy. Competes with ISES's Solar World Congress as a global gathering for the renewable-energy research and policy community.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat5 records

Key risks5 records

Key highlights7 records

Customer concentration

• Xx.com/ISES_Solar
• YouTubeyoutube.com/c/InternationalSolarEnergySocietyISESFreiburg
• Facebookfacebook.com/InternationalSolarEnergySociety
• LinkedInlinkedin.com/company/international-solar-energy-society

Compliance1 record

Revenue estimate

Valuation estimate

Number of profiles

Profiles4 records

Subsidiaries27 records

Funding overview

Funding rounds

Investors

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M&A

Investments

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Frequently asked questions about International Solar Energy Society