1. ABB Ltd.
2. Aboitiz Power Corporation
3. Altarock Energy Inc.
4. Ansaldo Energia
5. Atlas Copco AB
6. Berkshire Hathaway Energy
7. Calpine Corporation
8. CeraPhi Energy
9. Chevron Corp.
10. Climatemaster Inc.
11. Climeon
12. Comisi?n Federal de Electricidad
13. Contact Energy
14. Eavor Technologies Inc.
15. ElectraTherm Inc.
16. Enel Green Power S.p.A.
17. Engie SA
18. Exergy International
19. Fervo Energy
20. First Gen Corporation
21. Fuji Electric Co. Ltd.
22. GEG Power
23. General Electric SE
24. Geothermal Engineering Ltd.
25. Green Mountain Energy Company
26. Halliburton
27. Holtec International
28. HS Orka HF
29. Innergex Renewable Energy
30. JFE Engineering Corporation
31. Macquarie Group Limited
32. Marton Geotechnical Services Inc.
33. Mitsubishi Corporation
34. Northern California Power Agency
35. Ormat Technologies Inc.
36. Panax Geothermal
37. Pertamina Geothermal Energy
38. Pure Energy Holdings Corporation
39. Quaise Energy
40. Reykjavik Geothermal
41. Siemens AG
42. Sumitomo Corporation
43. Supreme Energy
44. TAS Energy Inc. by Comfort Systems USA
45. Tata Power Company Limited
46. Terra-Gen Power LLC
47. Tetra Tech Inc.
48. Thermax Ltd.
49. Toshiba International Corporation
50. Turboden S.P.A.
51. Yokogawa Electric Corporation