| REA GLOBAL | Redland Bay, Australia | Visit site |
| REAL ALPHA | Roma, Italy | Visit site |
| REAL ALPHA | Lugano, Switzerland | Visit site |
| REALI | Lima, Peru | Visit site |
| REALI | Peñalolén, Chile | Visit site |
| REALI | Miraflores, Peru | Visit site |
| REAR®(Renewable Energy Association of Rajasthan) - Industry Body - Solar Association - NGO | Kolayat, India | Visit site |
| REAR®(Renewable Energy Association of Rajasthan) - Industry Body - Solar Association - NGO | Jaipur, India | Visit site |
| REBI | San Sebastián de los Reyes, Spain | Visit site |
| REBI | Aranda de Duero, Spain | Visit site |
| REBI | Cuenca, Spain | Visit site |
| REBI | Guadalajara, Spain | Visit site |
| REBI | Móstoles, Spain | Visit site |
| REBI | Soria, Spain | Visit site |
| REBI | Valladolid, Spain | Visit site |
| REC Group | Staré Město, Czech Republic | Visit site |
| RECA SOLAR | Szczecin, Poland | Visit site |
| RECOM | Milano, Italy | Visit site |
| RED Engineering Design | London, United Kingdom | Visit site |
| REDEN | Saint-Julien-de-Concelles, France | Visit site |
| REDEN | Roquefort, France | Visit site |
| REECO Group | Reutlingen, Germany | Visit site |
| REECO Group | Germany | Visit site |
| REFENERGY I.K.E. | Greece | Visit site |
| REFU | Pfullingen, Germany | · |
| REGA ENERGY | Queluz, Portugal | Visit site |
| REGGIO | Santiago, Chile | Visit site |
| REGGIO | San Miguel, Chile | Visit site |
| REMA hydrogen | Lausanne, Switzerland | Visit site |
| REMONDIS Gruppe | Lünen, Germany | Visit site |
| REMONDIS Production GmbH | Lünen, Germany | Visit site |
| REMONDIS Sverige | Hisings Backa, Sweden | Visit site |
| RENAC Power | China | Visit site |
| RENAISSANCE CAPITAL d.o.o. | Zagreb, Croatia | Visit site |
| RENAISSANCE CAPITAL d.o.o. | Sesvete, Croatia | Visit site |
| RENOPI (Shenzhen) New Energy Technology Co., Ltd | 桃園區, Taiwan | Visit site |
| RENOVA, Inc. | 東京都, Japan | Visit site |
| RENOZ Energy | Perth, Australia | Visit site |
| RENQ Power Solutions India Pvt Ltd | Pala, India | Visit site |
| RENQ Power Solutions India Pvt Ltd | Kochi, India | Visit site |
| RENTALOAD | Gleizé, France | Visit site |
| RENTALOAD | France | Visit site |
| RENTALOAD | Germany | Visit site |
| RENTALOAD | Norway | Visit site |
| RENTALOAD | United Kingdom | Visit site |
| RENTALOAD | United States | Visit site |
| RENTALOAD | Frankfurt, Germany | Visit site |
| RENTALOAD | London, United Kingdom | Visit site |
| RENTALOAD | Amsterdam, Netherlands | Visit site |
| RENTALOAD | Paris, France | Visit site |
| RENTALOAD | Dublin, Ireland | Visit site |
| REPP (Renewable Energy Performance Platform) | London, United Kingdom | Visit site |
| REPROCON | Berlin, Germany | · |
| RER Energy Group México | Mexico City, Mexico | Visit site |
| RES | Kings Langley, United Kingdom | · |
| RESGREEN EUROPE SL | Alcorcón, Spain | Visit site |
| RESINC Solar & Batteries | Wyong, Australia | Visit site |
| REVCOO | Vénissieux, France | Visit site |
| REVTECH Wind Solutions | Fortaleza, Brazil | · |
| RFC Ambrian | Sydney, Australia | Visit site |
| RFC Power | London, United Kingdom | · |
| RHI Magnesita | Vienna, Austria | Visit site |
| RHINO ENERGY SOLUTIONS | Johannesburg, South Africa | Visit site |
| RINA | Genova, Italy | Visit site |
| RIOGLASS | Mieres, Spain | Visit site |
| RITEWAYS | Bengaluru, India | Visit site |
| RITEWAYS | India | Visit site |
| RM Surveys | Perth, Australia | Visit site |
| RM Surveys | Port Hedland, Australia | Visit site |
| RM Surveys | Kalgoorlie, Australia | Visit site |
| RM Surveys | Broome, Australia | Visit site |
| RM Surveys | Northam, Australia | Visit site |
| RM Surveys | Sydney, Australia | Visit site |
| RMB Hydroseeding | Dursley, United Kingdom | Visit site |
| RN Kablo | Denizli, Türkiye | Visit site |
| RNWBL Canada | Prince, Canada | · |
| RODINA Energy Group | Kyiv, Ukraine | · |
| ROEF | Son en Breugel, Netherlands | Visit site |
| ROHM Semiconductor Europe | Willich, Germany | Visit site |
| ROSI | Grenoble, France | Visit site |
| ROTORWORKS GmbH | Berlin, Germany | Visit site |
| ROYPOW Technology Co., Ltd. | · | Visit site |
| RP Global | Vienna, Austria | Visit site |
| RP Global | Madrid, Spain | Visit site |
| RP Solar | Chennai, India | Visit site |
| RPS Switchgear SA (Switchgear & Electrical Engineering Services) | Boksburg, South Africa | Visit site |
| RPS Switchgear SA (Switchgear & Electrical Engineering Services) | Johannesburg, South Africa | Visit site |
| RS Solar CAD Group | Ghaziabad, India | · |
| RS WINDTECH ENGINEERS (P) LTD | Thovala, India | Visit site |
| RS Windtech Engineers Private Limited | Thovala, India | Visit site |
| RSF Capital Partners LLP | London, United Kingdom | Visit site |
| RSK Group | Frodsham, United Kingdom | Visit site |
| RSK Renewables | Stirling, United Kingdom | Visit site |
| RSM Energy | Neuhausen am Rheinfall, Switzerland | · |
| RSM Spain | Barcelona, Spain | Visit site |
| RTS Wind AG | Bremen, Germany | Visit site |
| RTS Wind UK | Middlesbrough, United Kingdom | Visit site |
| RUDRA SOLAR ENERGY | Ahmedabad, India | Visit site |
| Rabbalshede Kraft AB | Rabbalshede, Sweden | Visit site |
| Rabot Dutilleul Construction | France | Visit site |
| Rabot Dutilleul Construction | Saint-Denis, France | Visit site |
| Rabot Dutilleul Construction | Belgium | Visit site |
| Radial Torque Tools B.V. | Soest, Netherlands | Visit site |
| Radiocrafts | Oslo, Norway | Visit site |
| Radiocrafts | OSLO, Norway | Visit site |
| Radsol Design Pvt. Ltd. | Jalandhar, India | · |
| Rahimafrooz Solar | Dhaka, Bangladesh | · |
| RaiffeisenVolt GmbH | Meschede, Germany | · |
| Raijin Solar Energy LLP | Ahmedabad, India | Visit site |
| RainStick | Toronto, Canada | Visit site |
| Rainbow Solar Melbourne Australia | Melbourne, Australia | Visit site |
| Rainbow Steel | Tianjin, China | Visit site |
| Raiseking Lighting | Guangzhou Shi, China | Visit site |
| Raj Petro - A Brenntag Group Company | Chennai, India | Visit site |
| Raj Petro - A Brenntag Group Company | Mumbai, India | Visit site |
| Rajdeep Solar Energy Private Limited | Ahmedabad, India | Visit site |
| Rakumba Lighting | Melbourne, Australia | Visit site |
| Ram Raja Solar Power Green Energy | Jhansi, India | Visit site |
| Ramboll | København, Denmark | Visit site |
| Ramboll | · | Visit site |
| Ramboll | Denmark | Visit site |
| Ramboll | Finland | Visit site |
| Ramboll | Germany | Visit site |
| Ramboll | Norway | Visit site |
| Ramboll | Sweden | Visit site |
| Ramboll | United Kingdom | Visit site |
| Ramery | Erquinghem-Lys, France | Visit site |
| Ramesh Corp. | Tripureswor, Nepal | Visit site |
| Ramón y Cajal Abogados | Madrid, Spain | Visit site |
| Rana Energy (Techstars ‘23) | London, United Kingdom | · |
| Rank® – Organic Rankine Cycle (ORC) and High-Temperature Heat Pumps (HTHP) | La Vall d'Uixó, Spain | Visit site |
| Rank® – Organic Rankine Cycle (ORC) and High-Temperature Heat Pumps (HTHP) | Spain | Visit site |
| Rapidsolar GmbH | Eime, Germany | Visit site |
| Rarlon PV Tech | Ningbo Shi, China | Visit site |
| Ras Ghareb Wind Energy | New Cairo, Egypt | Visit site |
| Ratan Green Energy Services Pvt. Ltd. | Jaipur, India | Visit site |
| Ravano Power | Cogoleto, Italy | Visit site |
| Ravindra Energy Limited | Mumbai, India | Visit site |
| RayGen | Melbourne, Australia | Visit site |
| Rayleigh Solar Tech | Dartmouth, Canada | Visit site |
| Rayleigh Solar Tech | Canada | Visit site |
| Raymetrics S.A. | Amarousio, Greece | Visit site |
| Raymetrics S.A. | Athina, Greece | Visit site |
| Raymond Solar | Årsta, Sweden | Visit site |
| Raymond Solar | Stockholm, Sweden | Visit site |
| Raymond Solar | Malmö, Sweden | Visit site |
| Raymond Solar | Göteborg, Sweden | Visit site |
| Raynow Energy | Nairobi, Kenya | Visit site |
| Rays Power Experts Ltd | Jaipur, India | · |
| Rays Power Infra Limited | Jaipur, India | · |