| Kyon Energy | München, Germany | · |
| Kyoto Fusioneering | 東京都, Japan | Visit site |
| Kyoto Group AS | Lysaker, Norway | · |
| KÖB Holzheiztechnik e.K. | Delmenhorst, Germany | · |
| L&T Construction | Chennai, India | Visit site |
| L&T Finance | Mumbai, India | Visit site |
| L&T Technology Services | Vadodara, India | Visit site |
| L'ENERGÈTICA | Barcelona, Spain | · |
| LAPORTE | Saint-Laurent, Canada | Visit site |
| LAPP India | Anekal, India | Visit site |
| LAPP India | Germany | Visit site |
| LAPP India | Bengaluru, India | Visit site |
| LAPP India | Bhopal, India | Visit site |
| LAPP India | Dharuhera, India | Visit site |
| LAUTEC Group | København, Denmark | Visit site |
| LC Energy | Wageningen, Netherlands | Visit site |
| LCA Energia Solar | Campos dos Goytacazes, Brazil | Visit site |
| LCB - groupe Face | Parigné-l'Évêque, France | Visit site |
| LCI Consultants | Melbourne, Australia | Visit site |
| LCP Delta | London, United Kingdom | Visit site |
| LDK Consultants | Athina, Greece | Visit site |
| LED Industries, Inc. | · | Visit site |
| LED Solar Street Light | India | Visit site |
| LEDAX Energia | Salvador, Brazil | Visit site |
| LEDI ÉTANCHÉITÉ | Vaulx-en-Velin, France | Visit site |
| LEDI ÉTANCHÉITÉ | Lyon, France | Visit site |
| LEDTSE | Las Palmas de Gran Canaria, Spain | Visit site |
| LEDsafari | Lausanne, Switzerland | Visit site |
| LEITWIND | Vipiteno, Italy | Visit site |
| LES EOLIENNES FLOTTANTES DU GOLFE DU LION | Montpellier, France | Visit site |
| LESSO Solar | Singapore, Singapore | · |
| LG Chem | Seoul, South Korea | Visit site |
| LG Solar Global | Seoul, South Korea | Visit site |
| LG Water Solutions | Seoul, South Korea | Visit site |
| LI JIN INDUSTRIAL CO LTD 立津國際 | 臺中市, Taiwan | Visit site |
| LIDELA - light design laboratory | Stuttgart, Germany | Visit site |
| LIFEPOWR | Antwerpen, Belgium | Visit site |
| LIGHTWORKS SERVICES LTD | Walsall, United Kingdom | Visit site |
| LILAN ENERGY | Madrid, Spain | Visit site |
| LILAN ENERGY | Bogotá, Colombia | Visit site |
| LIONTRON GmbH & Co. KG | Grefrath, Germany | Visit site |
| LITHTECH Battery Energy Storage System | Shenzhen Shi, China | Visit site |
| LIXIL | 東京都, Japan | Visit site |
| LK Power | Suzhou Shi, China | Visit site |
| LLC Solar Steelconstruction | Дніпро, Ukraine | · |
| LM Wind Power | Kolding, Denmark | Visit site |
| LMENG | Rio de Janeiro, Brazil | Visit site |
| LMS Energy | Adelaide, Australia | Visit site |
| LOCALPOWER || Energia Solar | Rio de Janeiro, Brazil | Visit site |
| LOGSTOR District Heating Solutions | Denmark | Visit site |
| LOHUM | Meerut, India | Visit site |
| LOWIND | Huarte, Spain | · |
| LR Energy | Gurugram, India | Visit site |
| LS Cable & System | Anyang-si, South Korea | Visit site |
| LSES-Lebanese Solar Energy Society | بيروت, Lebanon | Visit site |
| LT Solar GmbH | Bad Fischau-Brunn, Austria | Visit site |
| LUMENION | Berlin, Germany | · |
| LUNİ SOLAR ENERJİ A.Ş. | Konak, Türkiye | Visit site |
| LUXEL | Montpellier, France | · |
| LYS Energy | Singapore, Singapore | Visit site |
| La Bodega Solar | Tijuana, Mexico | Visit site |
| La Caisse (Caisse de dépôt et placement du Québec) | Montréal, Canada | Visit site |
| La Maison des Énergies Suisse | Morges, Switzerland | Visit site |
| La Maison du Solaire | Mies, Switzerland | Visit site |
| Lahmeyer International GmbH | Bad Vilbel, Germany | Visit site |
| Laing O'Rourke | Dartford, United Kingdom | Visit site |
| Lake Turkana Wind Power Limited | Nairobi, Kenya | Visit site |
| Lakestar | Roma, Italy | Visit site |
| Lakestar | London, United Kingdom | Visit site |
| Lakestar | Berlin, Germany | Visit site |
| Lakestar | Zürich, Switzerland | Visit site |
| Laketricity | Bordeaux, France | Visit site |
| Landatu Solar SL | Bilbao, Spain | Visit site |
| Landatu Solar SL | Etxebarri, Spain | Visit site |
| Landesverband Erneuerbare Energien NRW e.V. | Düsseldorf, Germany | Visit site |
| Landesverband Erneuerbare Energien Niedersachsen | Bremen e.V. | Hannover, Germany | Visit site |
| Landport Energy | Raamsdonksveer, Netherlands | Visit site |
| Landsvirkjun | Reykjavík, Iceland | Visit site |
| Lanxing Energy | China | Visit site |
| Large Battery | Dongwan Shi, China | Visit site |
| Larsen & Toubro Limited | Mumbai, India | Visit site |
| Laser Surveys Ltd | Malvern, United Kingdom | Visit site |
| Laser Surveys Ltd | Ingatestone, United Kingdom | Visit site |
| Laska Technology | Beşiktaş, Türkiye | Visit site |
| Laska Technology | Kağıthane, Türkiye | Visit site |
| Latent Drive | Dorchester, United Kingdom | Visit site |
| LayTec | Berlin, Germany | Visit site |
| Lead Solar | Nantong Shi, China | · |
| LeadPower | Shenzhen Shi, China | Visit site |
| Leaf Ingénierie | Boulogne-Billancourt, France | Visit site |
| Leapton Solar | 泉南郡, Japan | Visit site |
| Lecuso New Energy | Yangzhou Shi, China | Visit site |
| Ledcor | Vancouver, Canada | Visit site |
| Ledermüller - Energie Optimiert | Vorderweißenbach, Austria | Visit site |
| Ledvance | Garching bei München, Germany | Visit site |
| Leeka Corp. | Changzhou Shi, China | Visit site |
| Lees Power | Wuxi Shi, China | Visit site |
| Leeson Group | Melbourne, Australia | · |
| Leeson Legal | Dublin, Ireland | Visit site |
| Legacy Energy | Melbourne, Australia | · |
| Legal & General | London, United Kingdom | Visit site |
| Legendre | Saint-Jacques-de-la-Lande, France | Visit site |
| Leibniz-Institut für Photonische Technologien | Jena, Germany | Visit site |
| Lener Asesores legales y económicos | Madrid, Spain | Visit site |
| Lenercom Technology | Budapest, Hungary | · |
| Lenergy SpA | Calcinaia, Italy | Visit site |
| Leo Group Ltd | Halifax, United Kingdom | Visit site |
| Leoch Battery Global | Singapore, Singapore | Visit site |
| Leoch International Technology | Shenzhen Shi, China | · |
| Leon Solar | Barrackpore, India | Visit site |
| Les Éoliennes en Mer Services | Courbevoie, France | Visit site |
| Lesso New Energy | Fuoshan Shi, China | Visit site |
| Level Consulting Engineers Ltd. | Calgary, Canada | Visit site |
| Levidian | Cambridge, United Kingdom | Visit site |
| Levin Solar | Xiamen Shi, China | Visit site |
| Lexham Partners | London, United Kingdom | · |
| LeydenJar | Eindhoven, Netherlands | Visit site |
| LeydenJar | Leiden, Netherlands | Visit site |
| Leyton | France | Visit site |
| Li-Cycle | Toronto, Canada | · |
| Li-Metal | Toronto, Canada | · |
| Li-S Energy | Brisbane, Australia | Visit site |
| LiFT-PV B.V. | Arnhem, Netherlands | Visit site |
| Lianyungang Zhongfu Lianzhong Composites Group Co., Ltd. | Lianyungang Shi, China | Visit site |
| Liaoning Zlion Energy Co., Ltd. | 新竹市, Taiwan | Visit site |
| Liaoning Zlion Energy Co., Ltd. | China | Visit site |
| Licht Project | Halle, Germany | Visit site |
| LichtBlick SE | Hamburg, Germany | Visit site |
| Licovolt | Howth, Ireland | Visit site |
| Liebi LNC AG | Oey, Switzerland | Visit site |
| Life Energy | Kuwait City, Kuwait | Visit site |
| LifeGate Energy | Milano, Italy | Visit site |
| Light Leap | Årsta, Sweden | Visit site |
| Light Link | Dubai, United Arab Emirates | Visit site |
| Light Touch PLD | Dubai, United Arab Emirates | Visit site |
| Light Up The World (LUTW) | Calgary, Canada | Visit site |
| Light Up The World (LUTW) | Lima, Peru | Visit site |
| Lighten World | 臺北市, Taiwan | · |
| Lightenco | Ottawa, Canada | Visit site |
| Lightforce Solar | Auckland, New Zealand | Visit site |
| Lighting & Electrical Distributors | Melbourne, Australia | Visit site |
| Lighting Design International | London, United Kingdom | Visit site |
| Lighting Design Magazine | Athina, Greece | Visit site |
| Lightrock Power | Sheffield, United Kingdom | Visit site |
| Lightsource bp | London, United Kingdom | · |
| Lightspeed Solar | San Juan, Puerto Rico | · |
| Lightway Technology Development Limited | Shenzhen Shi, China | Visit site |
| Lightyears Solar | Auckland, New Zealand | Visit site |
| Liket Electirc Technology | Alexandria, Egypt | · |
| Lilac Technologies | Enugu East, Nigeria | Visit site |