F01K
Steam engine plants
Official title: STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES (gas-turbine or jet-propulsion plants F02; nuclear power plants, engine arrangements therein G21D)
F01K (Steam engine plants) appears on 6,750 US grants and 6,618 published applications in this corpus.
Search patents in F01K- Granted patents
- 6,750
- Published applications
- 6,618
- Assignees
- 2,065
- Inventors
- 10,970
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 109 | 0 |
| 1977 | 101 | 0 |
| 1978 | 91 | 0 |
| 1979 | 50 | 0 |
| 1980 | 70 | 0 |
| 1981 | 105 | 0 |
| 1982 | 85 | 0 |
| 1983 | 66 | 0 |
| 1984 | 98 | 0 |
| 1985 | 85 | 0 |
| 1986 | 69 | 0 |
| 1987 | 76 | 0 |
| 1988 | 59 | 0 |
| 1989 | 69 | 0 |
| 1990 | 67 | 0 |
| 1991 | 48 | 0 |
| 1992 | 40 | 0 |
| 1993 | 57 | 0 |
| 1994 | 57 | 0 |
| 1995 | 65 | 0 |
| 1996 | 59 | 0 |
| 1997 | 69 | 0 |
| 1998 | 79 | 0 |
| 1999 | 67 | 0 |
| 2000 | 88 | 0 |
| 2001 | 122 | 39 |
| 2002 | 94 | 69 |
| 2003 | 92 | 95 |
| 2004 | 75 | 151 |
| 2005 | 84 | 110 |
| 2006 | 96 | 129 |
| 2007 | 57 | 127 |
| 2008 | 68 | 133 |
| 2009 | 57 | 249 |
| 2010 | 97 | 328 |
| 2011 | 129 | 409 |
| 2012 | 161 | 386 |
| 2013 | 235 | 419 |
| 2014 | 306 | 434 |
| 2015 | 235 | 485 |
| 2016 | 303 | 443 |
| 2017 | 385 | 441 |
| 2018 | 377 | 361 |
| 2019 | 353 | 297 |
| 2020 | 344 | 271 |
| 2021 | 274 | 226 |
| 2022 | 229 | 259 |
| 2023 | 219 | 207 |
| 2024 | 220 | 249 |
| 2025 | 193 | 192 |
| 2026 | 116 | 109 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Main groups
Granted patents with any code in the group
- F01K 23/00Plants characterised by more than one engine delivering power external to the2,688
- F01K 25/00Plants or engines characterised by use of special working fluids, not otherwise1,876
- F01K 13/00General layout or general methods of operation of complete plants1,538
- F01K 7/00Steam engine plants characterised by the use of specific types of engine1,211
- F01K 3/00Plants characterised by the use of steam or heat accumulators, or intermediate1,019
- F01K 21/00Steam engine plants not otherwise provided for587
- F01K 9/00Plants characterised by condensers arranged or modified to co-operate with the engines484
- F01K 11/00Plants characterised by the engines being structurally combined with boilers or condensers456
All 14 main groupsShow fewer
- F01K 17/00Steam engine plants: using steam or condensate extracted or exhausted from steam429
- F01K 27/00Plants for converting heat or fluid energy into mechanical energy, not otherwise422
- F01K 15/00Adaptations of plants for special use295
- F01K 19/00Regenerating or otherwise treating steam exhausted from steam engine plant193
- F01K 5/00Plants characterised by use of means for storing steam in an alkali178
- F01K 1/00Steam accumulators59
Recent patents
- Thermal energy storage system coupled with a solid oxide electrolysis system6 Oct 2026US 12,753,710 B2Rondo Energy, Inc.
- Heat engine using a liquid-vapor-phase-changing material22 Sep 2026US 12,742,402 B2Lava Energy Ltd
- Steam supply system and steam supply method15 Sep 2026US 12,735,998 B2Mitsubishi Heavy Industries, Ltd.
- Two-phase thermal pump15 Sep 2026US 12,735,999 B2Rolls-Royce North American Technologies Inc.
- Sterically hindered hydrofluoroolefins with dipole moment and their blends with sterically hindered-olefins as refrigerants for high temperature heat pumps and working fluid for organic Rankine cycles8 Sep 2026US 12,729,332 B2Carbon Ventures, LLC
- System for reheat steam temperature turndown control in heat recovery steam generators8 Oct 2026US 2026/0309057 A1GE Vernova Infrastructure Technology LLC
- Ambient temperature thermal adapter for supercritical carbon dioxide power cycle8 Oct 2026US 2026/0309058 A1TerraPower, LLC
- Plant and process for energy management1 Oct 2026US 2026/0298112 A1Energy Dome S.P.A.
- Method of operating a heat cycle system, heat cycle system and method of modifying a heat cycle system1 Oct 2026US 2026/0298113 A1Noditech AB
- System and method for separation and use of nitrogen from inlet air or flue gas24 Sep 2026US 2026/0284593 A1GE Infrastructure Technology LLC
Most cited
By later US patents
- Hydrocarbon combustion power generation system with CO2 sequestration337US 6,389,814 B1Clean Energy Systems, Inc. · 2002
- Submersible power generators and method of operating thereof331US 9,651,032 B2General Electric Company · 2017
- Method of power generation via coal gasification and liquid hydrocarbon synthesis315US 3,986,349 AChevron Research Company · 1976
- Microcomponent chemical process sheet architecture299US 5,811,062 ABattelle Memorial Institute · 1998
- Medium-load power-generating plant with integrated coal gasification plant287US 4,608,818 AKraftwerk Union Aktiengesellschaft · 1986